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1
NUTRITIONAL ASSESSMENT OF SOME NEGLECTED AND
UNDERUTILIZED VEGETABLES WILDLY GROWN IN SINDH
Ph. D. THESIS
BY
BENISH NAWAZ MERANI
Reg. No. 2K12-FST-34
INSTITUTE OF FOOD SCIENCES & TECHNOLOGY
FACULTY OF CROP PRODUCTION,
SINDH AGRICULTURE UNIVERSITY
TANDOJAM, SINDH, PAKISTAN
2018
2
NUTRITIONAL ASSESSMENT OF SOME NEGLECTED AND
UNDERUTILIZED VEGETABLES WILDLY GROWN IN SINDH
BY
BENISH NAWAZ MERANI
A THESIS SUBMITTED TO SINDH AGRICULTURE UNIVERSITY,
THROUGH THE INSTITUTE OF FOOD SCIENCES &
TECHNOLOGY, FACULTY OF CROP PRODUCTION, IN
CONNECTION WITH THE FULFILLMENT OF THE
REQUIREMENTS
FOR
THE DEGREE OF
DOCTOR OF PHILOSOPHY
IN
FOOD SCIENCE AND TECHNOLOGY
TANDOJAM, SINDH, PAKISTAN
2018
3
DEDICATION
I dedicate this thesis to my Parents and
Husband for their dedicated partnership for
success in my life
4
TABLE OF CONTENTS
CHAPTER PARTICULARS PAGE
APPROVAL CERTIFICATE BY SUPERVISORY
COMMITTEE i
RESEARCH CERTIFICATE ii
THESIS RELEASE FORM iii
HALF TITLE PAGE iv
ACKNOWLEDGEMENT v
LIST OF TABLES vi
LIST OF FIGURES ix
LIST OF APPENDICES xi
ABBREVIATIONS xiv
ABSTRACT xv
I INTRODUCTION 1
II REVIEW OF LITERATURE 14
III MATERIALS AND METHODS 40
IV RESULTS 74
V DISCUSSION 162
VI CONCLUSIONS AND RECOMMENDATIONS 187
VII REFERENCES 196
APPENDICES 227
i
NUTRITIONAL ASSESSMENT OF SOME NEGLECTED AND
UNDERUTILIZED VEGETABLES WILDLY GROWN IN SINDH
BY
BENISH NAWAZ
APPROVAL CERTIFICATE BY SUPERVISORY COMMITTEE
I. SUPERVISOR DR. SAGHIR AHMED SHEIKH
Professor
Faculty of Crop Production
Sindh Agriculture University, Tando Jam.
II. CO-SUPERVISOR-I DR. SHAFI MUHAMMAD NIZAMANI
Professor
Faculty of Crop Protection
Sindh Agriculture University,
Tando Jam.
III CO-SUPERVISOR-II DR. AIJAZ HUSSAIN SOOMRO
Professor
Institute of Food Sciences & Technology,
Faculty of Crop Production
Sindh Agriculture University, Tando Jam.
DATE OF THE THESIS DEFENSE __________________________2017
ii
INSTITUTE OF FOOD SCIENCES & TECHNOLOGY
FACULTY OF CROP PRODUCTION
SINDH AGRICULTURE UNIVERSITY, TANDOJAM
RESEARCH CERTIFICATE
This is to certify that the present research work entitled “NUTRITIONAL
ASSESSMENT OF SOME NEGLECTED AND UNDERUTILIZED
VEGETABLES WILDLY GROWN IN SINDH” embodied in this thesis has been
carried out by Ms. Benish Nawaz under my supervision and guidance in connection with
fulfillment of the requirements for the degree of doctor of Philosophy in Food Sciences
and Technology and that the research work is original.
Date _______________2018
Prof. Dr. Saghir Ahmed Sheikh
Dean
&
Research Supervisor
iii
SINDH AGRICULTURE UNIVERSITY, TANDOJAM
THESES RELEASE FORM
I, Benish Nawaz Merani hereby authorize the Sindh Agriculture University, Tandojam
to supply copies of my thesis to libraries and individuals upon their request.
__________________
Signature
__________________
Dated
iv
NUTRITIONAL ASSESSMENT OF SOME NEGLECTED AND
UNDERUTILIZED VEGETABLES WILDLY GROWN IN SINDH
BY
BENISH NAWAZ MERANI
v
ACKNOWLEDGEMENTS
I am grateful to Almighty Allah, the supreme, the merciful, the most gracious,
the compassionate, the beneficent, who is the entire and only source of every knowledge
and wisdom gifted to mankind and who blessed me with the ability to do this work.
I would like to convey my cordial gratitude and appreciation to my eminent
supervisors Dr. Saghir Ahmed Sheikh, Dean Faculty of Crop Prodcution, Dr. Shafi
Muhammad Nizamani, Professor National Center of Excellence in Analytical Chemistry
and Dr. Aijaz Hussain Soomro, Director Institute of Food Sciences and Technology. I
could not achieve this goal without their thought provoking guidance, cooperation and
moral support. They have always been a source of inspiration and a role model for me.
Their patience and generosity has enabled me to overcome all the hurdles coming in the
way of success. Their teachings have not only improved my research skills but also
refined me as human.
I am profoundly obliged to Dr. Aasia Akbar Panhwar for her unconditional
support and cooperation. Her brilliance in the field of research, knowledge, wisdom, love
and care helped me greatly to achieve my research goals. I would like to extend my
thanks to Prof. Dr. Shahabuddin Memon, Director National Center of Excellence in
Analytical Chemistry, University of Sindh Jamshoro for providing me an opportunity to
do part of my Ph.D. research and for providing good research facilities throughout the
course of research
I am also gratified to Ms. Nusrat Shahab Memon, Research Associate, IFST, SAU
Tandoja and all faculty members for their research consultancy and cooperation.
At last but not the least, I really acknowledge and offer my heartiest gratitude to
my beloved parents, husband, brothers and friend Mahvish Jabeen Channa for their great
sacrifice, moral support, cooperation, encouragement, patience, tolerance and prayers for
my health and success during this work.
Finally, I would acknowledge the Higher Education Commission Pakistan (HEC)
for providing me an opportunity and financial support to achieve this goal.
BENISH NAWAZ MERANI
vi
LIST OF TABLES
Table
No. PARTICULARS
Page
No.
1 Enumeration of selected vegetables 47
2 Percentage non-edible and edible parts of the selected vegetables 51
3 Cooking methodology of amaranthus, lambs quarter, gram leaves,
horse radish tree flowers and spinach 53
4 Coding of nontraditional and commercial vegetables 54
5 HPLC conditions for quantification of vitamins 65
6 Perception of non-traditional leafy vegetable use by selected
respondents (% frequency) 75
7 Moisture content (%) of different types of vegetables under the effect
of postharvest processing methods 76
8 Ash content (%) of different types of vegetables under the effect of
postharvest processing methods 78
9 Protein content (%) of different types of vegetables under the effect of
postharvest processing methods 80
10 Fat (%) of different types of vegetables under the effect of postharvest
processing methods 82
11 Fiber content (%) of different types of vegetables under the effect of
postharvest processing methods 84
12 Carbohydrate (%) of different types of vegetables under the effect of
postharvest processing methods 86
13 Correlation matrix (r) of proximate composition of different
vegetables under the influence of processing treatments 87
14 Acetic acid (%) of different types of vegetables under the effect of
postharvest processing methods 88
15 Citric acid (%) of different types of vegetables under the effect of
postharvest processing methods 90
16 Oxalic acid (%) of different types of vegetables under the effect of
postharvest processing methods 91
17 Tartaric acid (%) of different types of vegetables under the effect of
postharvest processing methods 93
18 Correlation matrix (r) of organic acids of different vegetables under
the influence of processing treatments 94
19 Copper (mg 100g
-1) of different types of vegetables under the effect of
postharvest processing methods 95
20 Iron (mg 100g
-1) of different types of vegetables under the effect of
postharvest processing methods 97
21 Zinc (mg 100g
-1) of different types of vegetables under the effect of
postharvest processing methods 99
22 Manganese (mg 100g
-1) of different types of vegetables under the
effect of postharvest processing methods 101
vii
23 Calcium (mg 100g
-1) of different types of vegetables under the effect
of postharvest processing methods 103
24 Magnesium (mg 100g
-1) of different types of vegetables under the
effect of postharvest processing methods 105
25 Sodium (mg 100g
-1) of different types of vegetables under the effect
of postharvest processing methods 107
26 Potassium (mg 100g
-1) of different types of vegetables under the effect
of postharvest processing methods 109
27 Correlation matrix (r) of mineral content of different vegetables under
the influence of processing treatments 110
28 Alkaloids (mg g
-1) of different types of vegetables under the effect of
postharvest processing methods 112
29 Saponins (mg g
-1) of different types of vegetables under the effect of
postharvest processing methods 114
30 Flavinoids (mg g
-1) of different types of vegetables under the effect of
postharvest processing methods 116
31 Phenol (mg g
-1) of different types of vegetables under the effect of
postharvest processing methods 118
32 Phenol (mg g
-1) of different types of vegetables under the effect of
postharvest processing methods 120
33 Correlation matrix (r) of phytochemical content of different vegetables
under the influence of processing treatments 121
34 Vitamin A (β-carotene) content (mg 100g
-1) of different types of
vegetables under the effect of postharvest processing methods 123
35 Vitamin C (mg 100g
-1) of different types of vegetables under the
effect of postharvest processing methods 125
36 Vitamin B1 (mg 100g
-1) of different types of vegetables under the
effect of postharvest processing methods 127
37 Vitamin B2 (mg 100g
-1) of different types of vegetables under the
effect of postharvest processing methods 129
38 Vitamin B3 (mg 100g
-1) of different types of vegetables under the
effect of postharvest processing methods 131
39 Correlation matrix (r) of vitamin content of different vegetables under
the influence of processing treatments 132
40 Total solids (%) of different types of vegetables under the effect of
postharvest processing methods 134
41 Total soluble solids (°Brix) of different types of vegetables under the
effect of postharvest processing methods 136
42 Energy value (kcal 100g
-1) of different types of vegetables under the
effect of postharvest processing methods 137
43 pH level of different types of vegetables under the effect of
postharvest processing methods 139
44 Nitrogen free extract (%) of different types of vegetables under the
effect of postharvest processing methods 141
45 Total fatty acids (%) of different types of vegetables under the effect 143
viii
of postharvest processing methods
46
Correlation matrix (r) of Nitrogen free extract, energy value, fatty
acid, pH, total solids and TSS of different vegetables under the
influence of processing treatments
145
47 Chlorophyll content of fresh vegetables selected in the present study 146
48 Five point scale sensory scores of raw or uncooked non-traditional
vegetables 147
49 Five point scale Sensory scores of non-traditional vegetables cooked
by traditional method 151
50 Extraction of components by using eigen values and variability
percentage 156
51 Analysis of component score coefficient matrix 159
52 Component correlation matrix 160
ix
LIST OF FIGURES
Table
No. PARTICULARS
Page
No.
1 Schematic representation of the methodology used in the present study 41
2 Map showing selected district of Sindh Province, Pakistan 43
3 Pictorial view of selected vegetables 48
4 Perception of nontraditional vegetable use 75
5 Graphical representation of the moisture content (%) of selected
vegetables 77
6 Graphical representation of the ash content (%) of selected vegetables 78
7 Graphical representation of the protein content (%) of selected vegetables 80
8 Graphical representation of the fat content (%) of selected vegetables 82
9 Graphical representation of the fiber content (%) of selected vegetables 84
10 Graphical representation of the carbohydrate content (%) of selected
vegetables 86
11 Graphical representation of the acetic acid (%) of selected vegetables 89
12 Graphical representation of the citric acid (%) of selected vegetables 90
13 Graphical representation of the oxalic acid (%) of selected vegetables 92
14 Graphical representation of the tartaric acid (%) of selected vegetables 93
15 Graphical representation of the copper content (mg 100g-1) of selected
vegetables 96
16 Graphical representation of the iron content (mg 100g
-1) of selected
vegetables 97
17 Graphical representation of the zinc content (mg 100g
-1) of selected
vegetables 99
18 Graphical representation of the manganese content (mg 100g
-1) of selected
vegetables 101
19 Graphical representation of the calcium content (mg 100g
-1) of selected
vegetables 103
20 Graphical representation of the magnesium content (mg 100g
-1) of
selected vegetables 105
21 Graphical representation of the sodium content (mg 100g
-1) of selected
vegetables 107
22 Graphical representation of the potassium content (mg 100g
-1) of selected
vegetables 109
23 Graphical representation of the alkaloids (mg g-1
) of selected vegetables 112
24 Graphical representation of the saponins (mg g-1
) of selected vegetables 114
25 Graphical representation of the flavinoids (mg g-1
) of selected vegetables 116
26 Graphical representation of the phenols (mg g-1
) of selected vegetables 118
27 Graphical representation of the tanins (mg g-1
) of selected vegetables 120
28 Graphical representation of the vitamin A (β-carotene) content (mg
100g-1
) of selected vegetables 123
29 Graphical representation of the vitamin C (mg 100g
-1) of selected
vegetables 125
x
30 Graphical representation of the vitamin B1 (mg 100g
-1) of selected
vegetables 127
31 Graphical representation of the vitamin B2 (mg 100g
-1) of selected
vegetables 129
32 Graphical representation of the vitamin B3 (mg 100g
-1) of selected
vegetables 131
33 Graphical representation of the total solids (%) of selected vegetables 134
34 Graphical representation of the total soluble solids (°Brix) of selected
vegetables 136
35 Graphical representation of the energy value (kcal 100g
-1) of selected
vegetables 138
36 Graphical representation of the pH of selected vegetables 139
37 Graphical representation of the nitrogen free extract (%) of selected
vegetables 141
38 Graphical representation of the total fatty acid (%) of selected vegetables 143
39 Graphical representation of the total chlorophyll (%) of selected
vegetables 146
40 Spider chart showing five point scale sensory scores of uncooked
amaranthus vegetable 148
41 Spider chart showing five point scale sensory scores of uncooked lambs
quarter vegetable 148
42 Spider chart showing five point scale sensory scores of uncooked gram
leaves vegetable 149
43 Spider chart showing five point scale sensory scores of uncooked horse
radish tree flowers vegetable 149
44 Spider chart showing five point scale sensory scores of uncooked spinach
vegetable 150
45 Spider chart showing five point scale sensory scores of cooked
amaranthus vegetable 151
46 Spider chart showing five point scale sensory scores of cooked lambs
quarter vegetable 152
47 Spider chart showing five point scale sensory scores of cooked gram
leaves vegetable 152
48 Spider chart showing five point scale sensory scores of cooked horse
radish tree flowers vegetable 153
49 Spider chart showing five point scale sensory scores of cooked spinach
vegetable 153
50 Scree plot of the eigenvalues 157
51 3D component plot of the nutritional data of vegetables 161
xi
LIST OF APPENDICES
APPENDIX PARTICULARS PAGES
I
Best of fit curve of minerals standards (Calcium, Copper,
Iron, Zinc, Manganese, Magnesium, Sodium and
potassium)
227
II
Best of fit curve of vitamin standards (vitamin A (β-
carotene), vitamin C (Ascorbic acid), vitamin B1
(Thiamine), vitamin B2 (Ribofilavin) and vitamin B3
(Niacin))
229
III
Best of fit curve of chromatograms of vitamin standards
(vitamin B1 (Thiamine), vitamin B2 (Ribofilavin), vitamin
B3 (Niacin), vitamin A (β-carotene) and vitamin C
(Ascorbic acid)
230
IV Best of fit curve of phytochemical standards (total
flavonoids, total phenols and total tanins) 233
V Analysis of variance for moisture content of various
vegetables and processing methods 234
VI Analysis of variance for ash content of various vegetables
and processing methods 234
VII Analysis of variance for protein content of various
vegetables and processing methods 234
VIII Analysis of variance for fat content of various vegetables
and processing methods 234
IX Analysis of variance for fiber content of various
vegetables and processing methods 235
X Analysis of variance for carbohydrate content of various
vegetables and processing methods 235
XI Analysis of variance for acetic acid of various vegetables
and processing methods 235
XII Analysis of variance for citric acid of various vegetables
and processing methods 235
XIII Analysis of variance for oxalic acid of various vegetables
and processing methods 236
XIV Analysis of variance for tartaric acid of various vegetables
and processing methods 236
XV Analysis of variance for copper content of various
vegetables and processing methods 236
XVI Analysis of variance for iron content of various vegetables
and processing methods 236
XVII Analysis of variance for zinc content of various vegetables
and processing methods 237
xii
XVIII Analysis of variance for manganese content of various
vegetables and processing methods 237
XIX Analysis of variance for calcium content of various
vegetables and processing methods 237
XX Analysis of variance for magnesium content of various
vegetables and processing methods 237
XXI Analysis of variance for sodium content of various
vegetables and processing methods 238
XXII Analysis of variance for potassium content of various
vegetables and processing methods 238
XXIII Analysis of variance for alkaloids of various vegetables
and processing methods 238
XXIV Analysis of variance for saponins of various vegetables
and processing methods 238
XXV Analysis of variance for flavinoids of various vegetables
and processing methods 239
XXVI Analysis of variance for phenol of various vegetables and
processing methods 239
XXVII Analysis of variance for tanins of various vegetables and
processing methods 239
XXVIII Analysis of variance for vitamin A of various vegetables
and processing methods 239
XXIX Analysis of variance for vitamin C of various vegetables
and processing methods 240
XXX Analysis of variance for vitamin B1 of various vegetables
and processing methods 240
XXXI Analysis of variance for vitamin B2 of various vegetables
and processing methods 240
XXXII Analysis of variance for vitamin B3 of various vegetables
and processing methods 240
XXXIII Analysis of variance for total solids of various vegetables
and processing methods 241
XXXIV Analysis of variance for total soluble solids of various
vegetables and processing methods 241
XXXV Analysis of variance for energy value of various
vegetables and processing methods 241
XXXVI Analysis of variance for pH of various vegetables and
processing methods 241
XXXVII Analysis of variance for nitrogen free extract of various
vegetables and processing methods 242
XXXVIII Analysis of variance for total fatty acids of various
vegetables and processing methods 242
xiii
XXXIX Analysis of variance for total chlorophyll of various
vegetables 242
XL Correlation matrix (r) of quality parameters of different
vegetables under the influence of processing treatments 243
XLI Analysis of variance for sensory analysis of uncooked
vegetables 244
XLII Analysis of variance for sensory analysis of cooked
vegetables 244
XLIII Informed consent 245
XLIV Questionnaire non-traditional vegetables 246
XLV Sensory evaluation form for cooked vegetables 247
XLVI Sensory evaluation form for raw or uncooked vegetables 248
xiv
ABBREVIATIONS
% Percent
< Less Than
µl Microliter
ANOVA Analysis of Variance
AOAC Association of The Analytical Chemists
Ca Calcium
CRD Complete Randomized Design
Cu Copper
Cv Coefficient of Variance
FAO Food and Agriculture Organization
Fe Iron
FW Fresh Weight
GOP Government of Pakistan
G Gram
GAE Gallic Acid Equivalent
HPLC High Performance Liquid Chromatography
IFST Institute of Food Sciences and Technology
K Potassium
Kcal Kilocalories
LDL Low Density Lipoprotein
LSD Least Significant Difference
M Mole
Mg Magnesium
Mg Milligram
mg kg-1
Milligram Per Kilogram
mg g-1
Milligram Per Gram
Min Minute
Ml Milliliter
Mn Manganese
Nm Nanometer
NS Nonsignificant ᴼC Degree Centigrade
Ppm Parts Per Million
Rpm Round Per Minute
SAU Sindh Agriculture University
SPSS Statistical Package for The Social Sciences
TSS Total Soluble Solids
UV–Vis Ultra Violet Visible
WHO World Health Organization
Zn Zinc
Μm Micrometer
xv
AN ABSTRACT OF THE THESIS OF
BENISH NAWAZ MERANI For Doctor of Philosophy in
Major Food Sciences & Technology
TITLE: NUTRITIONAL ASSESSMENT OF SOME NEGLECTED AND
UNDERUTILIZED VEGETABLES WILDLY GROWN IN SINDH
The aim of this study was to investigate the utilization potential and
comparison of nutritional value of nontraditional with commercial vegetables in Sindh.
The questionnaire survey methodology was used to collect the data on the utilization and
consumption of nontraditional and commercial vegetables in Mirpurkhas of Sindh
province, Pakistan in 2014. On the basis of survey spinach, horse radish tree flowers,
lambs quarter and gram leaves were collected in January, 2014 whereas, amaranthus was
collected in the months of July-August, 2014 from district Mirpurkhas, packed with
proper labelling and brought to the Institute of Food Sciences and Technology, Sindh
Agriculture University Tandojam for processing and nutritional analysis. The edible parts
of vegetables were washed and divided into five sets namely control, boiled, cooked,
thermally dehydrated and shade dried.
The data of survey showed that gram leaves was the most popular non-
traditional vegetable eaten frequent or occasionally by 82% respondents only 18%
respondents never tasted or do not know this vegetable. Next vegetables which majority
of respondent never tasted or did not know included amaranthus and lambs quarter.
About 62% respondents never tasted or do not know horse radish tree flowers as
vegetable while 38% respondents answered they eat occasionally.
The nontraditional (lambs quarter, horse radish tree flowers, gram leaves,
amaranthus) and commercial (spinach) vegetables were analyzed for their nutritive,
mineral, vitamin, phytochemical and chlorophyll composition. The highest moisture
content (92.66%) was found in spinach under boiled method followed by 88.760%
moisture content in the same vegetable at fresh (control). Maximum ash content (16.15%)
in horse radish tree flowers followed by 10.56% ash content in amaranthus under
thermally dehydration. Protein content was found greater (7.56%) in gram leaves under
thermal dehydration method. However, minimum protein of 1.04% was found in spinach
under boiling method. The maximum value of 3.85% in horse radish tree flowers under
cooking method while minimum fat content i.e. 0.85 and 0.75% was found in spinach and
lambs quarter, respectively at boiling method. The highest value (13.35%) of fiber was
obtained in thermally dried sample of horse radish tree flowers whereas the lowest value
was recorded in boiled sample of spinach. However, higher carbohydrate (68.62%)
content was found in lambs quarter at shade drying. The nontraditional vegetables also
contain organic acids (e.g. lactic acid, citric acid, acetic acid, tartaric acid) in all the
selected vegetables. The nontraditional and commercial vegetables were also recorded
with significant amount of vitamins and phytochemicals. The energy value was found
lowest in fresh spinach (38.35 Kcal 100g-1
) hence was also detected lowered in other
processing methods as compared to nontraditional vegetables.
xvi
The results of the sensory evaluation of the uncooked and cooked samples
in present study revealed that in uncooked samples, horse radish tree flowers obtained
highest scores in appearance, color, odor, texture, taste, overall acceptability and
purchase i.e. 4.90, 4.70, 4.00, 3.90, 3.50, 3.80 and 3.80. While in traditionally cooked
samples lambs quarter and gram leaves retained original color and thus obtained the
highest scores in appearance and taste i.e. 3.70, 3.90 and 3.70, 3.50, respectively.
Acceptability study by hedonic scoring showed that nontraditional vegetables (horse
radish tree flowers, lambs quarter, and gram leaves and amaranthus) made by traditional
cooking were most acceptable as compared with commercial vegetable (spinach). These
nontraditional vegetables when consumed in cooked form could also be a good source of
nutrients.
Principal component analysis revealed that the first seven principal
components explained about 94.79% of the total variability in the observed parameters.
Moisture, total solid, ash, fiber, carbohydrate, nitrogen free extract, energy value, acetic
acid, citric acid, oxalic acid, tartaric acid, copper, iron, zinc, manganese, calcium, sodium
and potassium resulted the most effective variables for the first principal component.
Saponins, flavinoids, phenol and vitamin B3 were major contributors to second principal
component, while tannins content was useful to define the third principal component.
It was concluded that the nutrient and bioactive contents obtained from
selected vegetables seem to suggest that the vegetables have high potential to contribute
to the nutritional and health status of local as well as urban communities in Sindh
Pakistan. Their use in the communities should therefore, be promoted. Taking into
account the amount of nutrient and bioactive content in the selected nontraditional
vegetable, these plants could be valuable and important contributor to the diets of the
people in Sindh, Pakistan.
1
CHAPTER-I
INTRODUCTION
Background
Vegetables are the major part of daily food intake by human population all
over the world that plays an important role in the balanced diet. Green vegetables are
excellent sources of micronutrients, so the consumption of these may contribute to meet
the nutritional requirement and to overcome the micronutrient deficiency at minimum
cost (Saikia and Deka, 2013; Ebert, 2014). People living in rural areas harvest wide
variety of vegetables including fruits, leaves, tubers and roots from barren lands because
of their flavor and traditional uses to overcome shortage of food or as supplement.
Nontraditional vegetables are regarded as famine or hunger food due to their potential to
meet the income security and food demand as rural people cannot afford commercial
crops (Jayanti et al., 2013). There are 350,000 plant species throughout the globe and
around 80,000 are fit for human consumption (Fuleky, 2016). The vegetables contain
essential nutrients, mineral elements and anti-nutritional constituents with significant
biological roles at physiological concentrations (Atabo et al., 2017).
Dietary diversity and consumption pattern of nontraditional vegetables
In developing countries various types of wild edible plants are consumed
as sources of food. Due to the sharp increase in population, scarcity of fertile land for
cultivation and high prices of available staples, some people frequently collect wild
2
edible plants and other plants from natural habitats to meet their adequate level of
nutrition (Seal et al., 2017). Local people since long time consume nontraditional
vegetables on daily basis but there is no any systematic investigation has been carried
out. In resource-poor settings worldwide, low-quality, monotonous diets are common and
the risk of micronutrient deficiencies is high (Arimond et al., 2010; FAO, 2013b) because
only few known commercial species are used for global supply of food (Barucha and
Pretty, 2010; FAO, 2013a). The leafy vegetables contain appreciable amounts of minerals
and vitamins, thus may be included in diets to supplement daily dietary allowances
needed by the body, hence, improving nutritional status and curbing the problem of
micronutrient deficiency (Akpana et al., 2017).
In Pakistan, comparatively to other developing nations, an expected 80%
of the rural populace relies on nontraditional wild plants for their primary health care
needs (Khan, 2012). Several plants are utilized for medicinal and nutritional purposes.
Currently, there is an upsurge in the utilization of plants believed to possess high
nutritional and medicinal value by most locals especially those in developing countries.
The leaf part of vegetables is very rich source of essential minerals and amino acids that
are needed for proper function of the body system. Also, it is a rich source of energy and
relatively safe for consumption owing to its very low concentrations of antinutrients and
toxic elements (Ewere et al., 2017). In the course of the most recent decades, there has
been icreasing scientific and commercial concern in Pakistan for nontraditional
vegetables, mainly due to their economic potential and the wide spread cultural
acceptability of plant based products (Sher et al., 2014, 2015). In some regions of the
3
world, use of nontraditional vegetables and culinary herbs are wide spread, where these
nontraditional vegetables plant species are regarded as important healthy food (Afolayan
and Jimoh, 2009). These vegetables could be incorporated in food formulation as
therapeutic agent apart from its nutritional essence which could be explored to provide
affordable remedy to masses. Lesser known vegetables, has enormous nutritional
potentials and can favorably be used as a substitute for most of the commonly used
vegetables (Agarwal et al., 2017).
Today, there is evidence that edible nontraditional plants have been used
as vegetables since ancient times for their organoleptic, therapeutic and medicinal
properties (Guarrera and Savo, 2013) and are nutritionally important because of high
content of minerals, essential fatty acids, fibers and proteins (Jabeen et al., 2010; Ghani et
al., 2012). The nontraditional vegetables contain appreciable amounts of macro-minerals
like magnesium, calcium, potassium and phosphorus, which work synergistically to
maintain optimal health by keeping the body and tissue fluids from being either too acidic
or too alkaline; allowing for exchange of nutrients between body cells (Akpana et al.,
2017). Many nontraditional vegetables are also used with staple food in both urban and
rural areas. The nontraditional vegetables traditionally used as food that enhances the
taste and color of the diets but scientific data on the nutrients and chemical composition
of those nontraditional vegetables is still scarce (Satter et al., 2016). Therefore, the use of
edible nontraditional vegetables appears attractive for the reason that they are a source of
healthy compounds, but they are less understood than commercial vegetables (Guil-
Guerrero, 2014).
4
Nutritional and medicinal importance of nontraditional vegetables
Pakistan is rich in nontraditional vegetables plants and it incorporates just
about 6000 blossoming plants which have extraordinary dietary and therapeutic
significance. In Pakistan 200 distinctive plant species are utilized to treat diarrhea, skin
problems, kidney maladies, gastrointestinal ailments and urinary sicknesses (Hayat et al.,
2008). They are profitable in keeping up basic store in the body and are esteemed
principally for their high vitamin, dietary fiber and mineral substance. The wide variety
in texture, color and tastes of different vegetables has added an intriguing touch to meal
(Fasuyi, 2006). Vegetable leaves have appreciable amount of nutrients such as calcium,
potassium, iron, carbohydrate, fat, protein and anti-nutrients. This therefore, suggests that
the leafy vegetable could serve as a constituent of human diet, supplying the body with
micronutrients which are electrolytes proffering significant roles in humans (Atabo et al.,
2017).
There is now growing evidence that nontraditional vegetables have higher
nutritional value than several known common vegetables (Orech et al., 2007). These
vegetables present good nutritional sources with moderate energy values and rich sources
of macronutrients and micronutrients, exhibiting the least toxic risks regarding heavy
metals (Attaa et al., 2017) and are good source of nutrition of any food and rich source of
vitamins, phytonutrients and minerals which protect our eyes from age-related problems
(such as age-related muscular degeneration) and omega-3 fatty acids which protect us
5
from cardiovascular diseases. The nontraditional vegetables can therefore, provide
substantial nutritional and dietary benefits to tribal populations living in remote rural
areas and can prevent several chronic diseases caused by malnutrition (Geeta and
Sharma, 2015). The vegetables are rich sources of protein which can encourage their use
in human diets and might be helpful for protein energy malnutrition. Vegetables are rich
sources of fiber which is an important component in preventing overweight, constipation,
diabetes, cholesterol, cardiac diseases, colon and breast cancer, hypertension, etc (Koca et
al., 2015). Nontraditional vegetables have been recognized as a good source of vegetable
fiber and protein content and showed lower value for total phenols, flavonoids content
but higher free radical scavenging activity as compared to cultivated vegetables.
Therefore, both these vegetables possess strong anti antioxidative potential to manage
against metabolic disorders such as diabetes and cardiovascular diseases (Agarwal et al.,
2017).
The intake of nontraditional vegetable plants is important for human
health and vegetables play a critical nutritive part in such manner, particularly for country
populaces (Uusiku et al., 2010). Nontraditional vegetables provide the bulk of daily
calories and around 65% of the protein (Bennett, 2016). Interest in nontraditional
vegetables has significantly increased in light of the fact that they give high supplement
levels and potential medical advantages (Garcia-Herrera et al., 2014b). Consequently,
many people harvest nontraditional vegetables also because of their significant impact to
the diet in terms of healthy compounds for example, vitamins, minerals and antioxidants.
Consequently, the tradition of eating spontaneous plants is still alive as well as is
6
expanding since the nontraditional vegetables are regarded as healthy and natural foods
(Uusiku et al., 2010; Pereira et al., 2011; Renna and Gonnella, 2012; Sanchez-Mata et
al., 2012).
The utilization of green vegetables plays an important role in keeping a
balanced diet and turns away the diseases related to malnourishment. Epidemiological
studies show that an increased consumption of plant based products is related to lessened
danger of various chronic health dieases including cardiovascular, neurodegenerative and
cancer diseases (Yahia, 2010). The phytochemical composition revealed the presence of
considerable levels of phenolics, flavonoids, alkaloids, and tannins among all the
nontraditional vegetables (Attaa et al., 2017) with various biological activities (Dinda et
al., 2007a, 2007b; Podsedek, 2007). These phytochemicals are accounted for several
biological activities, such as anti-cancer, anti-inflammatory, antioxidant, and
antimicrobial activities. Particularly, phenolic compounds which have antioxidant
characteristics (Mertz et al., 2009) with free radical scavenging capacity and strong
chain-breaking which in turn provide defensive mechanism against reactive oxygen
species (ROS) (Podsedek, 2007; Attaa et al., 2017) that are responsible for tissue and
oxidative damage to proteins and nucleic acids (Middleton et al., 2008). The low sodium
make these plants healthy alternative dietary components in the management and
prevention of hypertension (Akpana et al., 2017).
7
Most of wild edible vegetable species have medicinal property and can be
used to keep people healthy and fit. Furthermore, phytochemical and nutraceutical studies
of these edible species may provide better nutritional source. Apart from the source for
food, human also utilize plants for dyes, ornaments and medicines. Wild edible plants are
source for nutrition but also possess higher medicinal property. These wild plants are
grown in forest region without chemical / fertilizer (Seema, 2015). Dietary guidelines
encouraged the supplementation of plant-derived nutraceuticals not only to provide an
insight regarding assuaging nature, nutritional worth, sustainability and safe status but
also to modulate the onset of chronic ailments (Atta et al., 2016). Despite their common
utilization, the wide selection of nontraditional vegetables either semi-cultivated or
cultivates in the wild (Shakirin et al., 2010). The major nutritional compounds that are
present in nontraditional vegetable plants are carbohydrates in the form of starch and
sugars, protein, lipid, in the form of oil, vitamins, minerals, etc. Apart from these
antioxidants, like ascorbic acid, phenols such as cholorogenic acid and its polymers are
available in plant because of these component, the wild vegetable most have potential to
improve physical as well as mental health, help in reduce the risk of disease. There is
therefore a need to explore the vast varieties of nontraditional vegetables as food by man
(Edogbanya, 2016). All thenontraditional vegetables have very good medicinal potentials,
meet the standard requirements for drug formulation and serve as good sources of energy
and nutrients (Attaa et al., 2017).
8
Role of nontraditional vegetables in food security
Nontraditional vegetables can contribute to food security in several ways.
Harvesting and trading nontraditional vegetables can result in rural employment and
income generation (Keller et al., 2005; Agea et al., 2007; Barucha and Pretty, 2010;
Legwaila et al., 2011). It has been observed from various reports that there is lack of
knowledge and intake of nontraditional vegetables (Hart and Vorster, 2006; Modi et al.,
2006; Van-Rensburg et al., 2007; Lewu and Mavengahama, 2010; Taleni et al., 2012).
Malnutrition has affected around nine hundred million individuals throughout the globe
and more than two billion are recorded with micronutrient deficiency related diseases
(Fan et al., 2012). Nevertheless, some authors (Berti et al., 2014) hypothesized that by
including nontraditional vegetable species in the diets, there is likely to be an
improvement in nutrient deficiencies.
Bvenura and Afolayan (2015) stated that the increased consumption of
nontraditional vegetables will help to reduce the malnutrition and food insecurity.
Moreover, if availability of the traditional and nontraditional vegetables is made
throughout the year will results in food stability. This can be done by encouraging people
to cultivate the nontraditional vegetables in their home gardens during their season and
preserve them for later use in offseason. The horticultural perspectives of nontraditional
vegetables despite of their long history have not been fully examined (Odhav et al.,
2007). Bvenura and Afolayan (2015) reported that nontraditional vegetables are clearly
underutilized although they potentially have a big role to play in food security.
9
Nontraditional vegetables are required to be revitalized and widely consumed in daily
diets to decease food insecurity. The knowledge about these species may soon be lost if
these species to continuous underappreciated and neglected. Therefore, there is a dire
need for systematic investigation and records of their bioactive and nutritive values in
emerging countries (Hervert-Hernandez et al., 2011).
Main characteristics and adaption of nontraditional vegetables to harsh climates
Nontraditional vegetables and nontraditional crops grow well during
drought periods and in areas with low or unreliable rainfall. Nontraditional vegetables
require fewer inputs (chemical fertilizers and pesticides) during production survive poor
soils as they are adapted to the local environmental conditions and are available when the
commercial vegetables are not (Modi et al., 2006; Van-Vuuren, 2006). These vegetables
are probably free of agricultural contaminants; but, their impacts on human heath are
minimal known (Pieroni et al., 2002; Luczaj, 2010). In different studies, it was reported
that nontraditional vegetables have increased agro-biodiversity, upgraded production and
minimized the effects of pests, diseases and environmental shocks where other species
could fail (Tilman et al., 2006; Venter et al., 2007; Bradford, 2010; Frison et al., 2011;
Mahapatra and Panda, 2012; Asif and Kamran, 2013).
On account of their strength, nontraditional vegetables can act as security
nets in times of food deficiency and starvation (Kebu and Fassil, 2006). They may also
add to dietary diversity and be essential components of an otherwise monotonous and
10
nutritionally poor diet (Fentahun and Hager, 2009). Together with the lack of food
composition data on nontraditional vegetables, this has led to a routine undervaluation of
wild edible plants in diets and to their neglect by researchers, policy makers and
nutritionists (Figueroa et al., 2009). Besides, post-harvest losses and quality deterioration
of vegetables are mostly caused by pests, microbial infection, natural ripening processes
and environmental conditions such as heat, drought and improper post-harvest handling
(Idah et al., 2007; Olayemi et al., 2010).
Loss of indigenous knowledge and introduction of new commercial vegetables
The knowledge about nontraditional vegetables is decreasing which must
be documented (Aphane et al., 2003; Musinguzi et al., 2006; Lwoga et al., 2010).
Nontraditional plants, that are consumed as vegetables are actually part of the local
knowledge and production systems (Keller et al., 2004, 2005). Nontraditional vegetables
are those edible plants that are biologically indigenous to an area, while commercial
vegetables require various agricultural related inputs to grow. Indigenized vegetables are
local and adapted to the native environmental conditions (Laker, 2007). This loss in the
knowledge of nontraditional vegetables may contribute to decreased intake of plant
species which in turn results in micronutrient deficiency and food insecurity due to lack
of diet diversity (Flyman and Afolayan, 2008).
According to Keller et al. (2005) there are many factors that contribute to
the loss of knowledge about these species i.e. politics, lifestyle changes, introduction of
11
commercial crops and loss of habitat. The main reason for the loss of information about
nontraditional vegetables is the introduction and promotion of new commercial
vegetables by the agriculture extension and researchers, consequently leading to the
complete substitution of nontraditional vegetables (Jansen-van-Rensburg et al., 2007).
Commercial vegetables due to their popularity and market value are
keener about the farming of these commercial vegetables as compared with
nontraditional vegetables (Musinguzi et al., 2006). In many countries, nontraditional
vegetables have received negative attitude because of their primitiveness and poverty.
Thus, most of the population mainly youth, have stopped consumption of nontraditional
vegetables because they do not want to be labelled as backward (Jansen-van-Rensburg et
al., 2007).
Sensory (taste) and market potential
Earlier ethnobotanical surveys showed that value judgement can be done
on the basis of organoleptic qualities through which value of different species can be
judged (N’danikou et al., 2011). For example, if the respondents are given two species
and asked for their value, their response for one of the specie will be high because of its
taste. Kidane et al., (2015) carried out a survey to know which vegetable specie is most
preferred by the respondents on the basis of its taste. The chosen specie had the greater
market potential though marketability and was also influenced by other factors such as
quantity, accessibility and distribution.
12
Keeping in view, the present situation of ever increasing population,
urbanization and conversion of arable land in to residential areas, ultimately culminates
in the increased food demand leading to food in-security. The present study therefore, has
been designed to identify the wild vegetables suitable for human consumption. The study
planned would also indicate that the samples to be studied as good sources of macro and
micronutrients and to provide food security. There is always the need to explore every
possible source of nutrients for healthy living. The expected findings would also be
useful and helpful for nutritionists to formulate balance diets. The study shall also include
the effects of cooking and storage conditions on the nutrients of the vegetables
investigated and studied.
Problem statement and justification for the study
Literature review showed that extensive work has been done on the
nutritive components of various traditional in Pakistan; however, little attention has been
paid to the nutritive values of nontraditional vegetables. The findings obtained from
proposed study may guide researchers, scientists, health practitioners and above all, the
general public regarding wild vegetables that, these vegetables can not only contribute to
subsistence and nutritional requirement of the local people but can be a substantial
source of income generation against poverty alleviation particularly in rural areas of
Pakistan. Furthermore, identification of wild vegetables would help poor households to
have nutritive and affordable vegetables in comparison to other food items. The study
may provide valuable suggestions pertaining to other than formal sector in rural and peri-
13
urban areas because of their generally short labor intensive production systems, low
levels of investment and high yields. The present study may also help to identify the most
effective means of commercialization or best marketing and policy frameworks to
promote their use and maximize underutilized plant species having potentially economic
value.
Objectives of the study
The study shall be focused and attained through following objectives:
i. To assess the nutritional characteristics of selected wild vegetables
ii. To compare the nutritional characteristics of wild vegetables with other
commonly grown vegetables
iii. To determine the effect of processing and cooking on nutritional contents
of wild
vegetables
iv. To carry out the sensory attributes of cooked vegetables
v. To recommend the wild vegetables for human consumption, with
potentially
nutritive and health value
14
CHAPTER–II
REVIEW OF LITERATURE
Ethnobotanical information of nontraditional vegetables
Pakistan is bestowed with nontraditional vegetables plants with great
therapeutic importance. There are about 200 different plant species discovered having the
potential to treat urinary diseases, diarrhea, skin disorders, gastrointestinal diseases,
kidney diseases and dysentery (Sidhu et al., 2007; Hayat et al., 2008). Ethnobotany in
Pakistan is increasing with time and different studies have been recorded in various areas
(Qureshi and Bhatti, 2009; Qureshi et al., 2009a; Abbasi et al., 2010; Shinwari, 2010;
Bahadur, 2012; Farooq et al., 2012; Abbasi et al., 2013; Ahmad et al., 2014; Ullah et al.,
2014). Human consumption pattern for vegetables is limited to the introduced varieties
than wild habitats (Bussmann and Sharon, 2006; Cavender, 2006; Kunwar et al., 2006;
Pieroni et al., 2007).
Vegetables are considered most important in daily diet (Pandey, 2008).
The nontraditional vegetables despite of their medicinal values has been paid less
attention (Qureshi et al., 2006; Ahmad and Husain, 2008; Husain et al., 2008; Qureshi et
al., 2009; Mahmood et al., 2011c; Mahmood et al., 2012) and this field is regarded as
virgin (Mahmood et al., 2011a). The native individuals still prefer these wild plants as
medicines due to unaffordable costs of allopathic medicines, growing population,
15
incomplete health care systems and economic curbs (Mahmood et al., 2011b) but
unfortunately, this information is not documented properly on the ethno-medicinal
information from Pakistan (Mahmood et al., 2013). The nontraditional vegetables are
collected for home consumption by forest inhabitants, marginalized and tribal
communities or during indigenized festivals. None of the nontraditional vegetable plants
has been cultivated nor is the knowledge on nutritional properties still recorded or tapped.
These species are only consumed on the basis of their medicinal and taste values (Jayanti
et al., 2013).
Importance and utilization of nontraditional vegetables
Nontraditional vegetables are collected from both uncultivated and
cultivated lands and the information about nontraditional vegetables is passed on from
one generation to another generation as a part of the homegrown system of knowledge for
the local people (Lwoga et al., 2010). Throughout the most recent decades, there has been
an increasing commercial and scientific interest in Pakistan for nontraditional vegetables,
mostly because of their economic potential and the wide spread cultural acceptability of
plant based products (Sher et al., 2014, 2015). In Pakistan, comparatively to other
emerging countries, an expected 80% of the rural populace relies upon nontraditional
wild plants, for their essential health care needs (Khan, 2012). Today, there is proof that
edible nontraditional plant species have been used as vegetables since various decades
due to their medicinal and sensory attributes (Guarrera and Savo, 2013).
16
The use of edible nontraditional vegetables appears to be appealing in
light of the fact that they are appears to be appealing since they are a source of nutrients;
however, since they are less known than commercial vegetables (Guil-Guerrero, 2014).
Wild foods constitute an essential component of people's diets around the world
(Sanchez-Mata et al., 2012). However, apart from a handful of studies (Schunko and
Vogl, 2010; Schunko et al., 2012), quantitative data on wild food collection are scarce
and scattered. By wild edible plants we intend a food- centered subcategory of the
category utilized wild species (Maxted et al., 2011a, 2011b) that includes Crop Wild
Relatives (CWRs) and neglected crops that have the potential to diversify on-farm
production and regional diets. It mostly includes native species growing in their natural
habitat, but that may be managed, as well as introduced species that have been
domesticated (Hadjichambis et al., 2008; Menendez-Baceta et al., 2012). Despite the
wide spread use of nontraditional foods and their cultural importance, they lack
recognition as significant contributors to the human diet. Plant and animal domestication,
perhaps the most important cultural development of the past 13,000 years of human
history has resulted in the selection and use of a limited number of species for cultivation
and commercialization (Heinrich et al., 2006a, 2006b).
Scholars have shown that nontraditional vegetables often contain high
concentrations of minerals, proteins, vitamins A, C and significant percentages of fiber
than in cultivated vegetables (Alam et al., 2014). The nontraditional vegetables were
observed to be, relatively, good sources of vitamin B6 and ascorbic acid as they can
provide the recommended dietary allowance for daily healthy living (Akpana et al.,
17
2017). Nontraditional plants also generally contain a large spectrum of plant secondary
metabolic products like polyphenols, terpenoids, polysaccharides, nutraceuticals
(functional foods) which are potentially health-promoting agents. More than a simple
food, nontraditional vegetables may constitute proto-dietary supplements with
hypothetical cardio and chemo preventive properties (Visioli et al., 2004). Several plants
produce biologically active secondary metabolites mainly involved in plant defense
mechanisms (Visioli et al., 2011). Therefore, nontraditional plants are interesting sources
of potentially anti-bacterial products, which might theoretically be exploited in the
current search for novel antibiotics (Courvalin, 2016). The FAO (2010) reported that
nutrition and biodiversity converge to a common path leading to sustainable development
and food security and that wild species and intra species biodiversity have key roles in
global nutrition security. Accumulated evidence shows that wild edible plants provide
substantial health and economic benefits to developing countries (Shumsky et al., 2014).
The vegetables and their consumable parts differ from one area to another.
In many areas individuals eat leaves and in some they prefer the tubers, flowers and seeds
depending on the type of indigenous plant and the area or region. The edible parts are
mostly cooked as soups and stews. Concern has been communicated about the decrease
in the utilization of these vegetables. Nontraditional vegetables are at present neither
broadly consumed nor produced in vast amounts because people are not aware of their
nutritional quality and westernization prompted a negative impression of these vegetables
(Keith, 1992).
18
Policy makers and researchers have ignored nontraditional vegetables,
which resulted in too practically no data is accessible on their utilizations, cooking
techniques and healthful quality or bioavailability of their supplements. Recent research
shows that there are many nontraditional vegetables that could help to improve the
insufficient consumption of nutrients that has resulted from the inaccessibility of
commercial vegetables to marginal people (Modi et al., 2006; Van-Vuuren, 2006; Uusiku
et al., 2010). The decrease in the utilization of nontraditional vegetables can likewise be
ascribed to a reduction in the assortment of nontraditional vegetables and natural products
that are accessible. Moreover, there are various natural, political and financial reasons
that lie at the heart of indigenous learning misfortune with respect to nontraditional
vegetables (Adebooye and Opabode, 2004).
It is archived that nontraditional vegetables are utilized as nourishment
sources as well as therapeutic sources (Ezebilo, 2010). They are supposed to have
antiseptic properties and contain antioxidants, which helps in the prevention of cancer
and hypertension. They are not only used for dietary purpose but also therapeutic, as they
help to generate tissues and stimulate the immune system (Flyman and Afolayan, 2008).
The nontraditional vegetables also play an important role in income generation due to
low agricultural inputs during production (Adebooye and Opabode, 2004; Jansen-van-
Rensburg et al., 2007). In this context the analysis of wild edible plants is important to
identify the potential sources which could be exploited as alternative food (Seal et al.,
2017).
19
Nontraditional vegetables are likewise utilized as medicine. Adebooye and
Opabode (2004) recorded 24 nontraditional leafy vegetables that are utilized for
therapeutic purposes. These vegetables often contain low level of fat, hence, a staple food
for obese people. They are also rich in fiber, a feature that enhances them to decrease the
concentration of high cholesterol level in body (Tope et al., 2017). Lephole (2004)
carried out a survey in Lesotho and observed that 43.7% of the participants used
nontraditional vegetables for the treatment of diabetes and hypertension. The advantages
that nontraditional vegetables offer groups as a food source, income source and
therapeutic source to validate the need to decide current utilize and examine the
capability of future use. The protection of the related indigenous information is
fundamental for the handling and conservation of nontraditional vegetables. Moreover, it
is crucial to exchange the indigenous information to more youthful ladies to guarantee
that the use of nontraditional vegetables proceeds. The mentalities of particularly
youngsters towards nontraditional vegetables decide the potential for future utilization of
these vegetables as a nourishment source.
One reason that leads to lessened utilization of nontraditional vegetables is
unwillingness to walk long distances to assemble vegetables, as reported in the studies
headed by Viljoen et al. (2005) and Jansen-van-Rensburg et al. (2007). As far as parts
eaten, respondents reported that they eat for the most part the leaves except for some
nontraditional vegetables whose fruits are additionally eaten. Labadarios et al. (2005)
found in their study that individuals who grew their own nontraditional vegetables had a
higher consumption of minerals and vitamins. In this way, the production of
20
nontraditional vegetables is exceptionally prescribed as it gives dependable access to
nutritious foods. But, inferable from natural surroundings misfortune the accessibility of
nontraditional vegetables is not ensured (Keller et al., 2005; Viljoen et al., 2005).
The role of wild vegetables in household food security
Nontraditional vegetables are a typical and imperative source of food and
nourishment. These plant species which were at first essential sources of food in
numerous societies have been minimized. Micronutrient deficiencies, particularly in
youngsters, continue to be a worldwide concern and yet many reports have shown the
high nutritive value of nontraditional vegetables. If they are consolidated into the daily
diet, nontraditional vegetables can overcome some of the micronutrient related deficiency
diseases (Bvenura and Afolayan, 2015). The wild edible plants were rich in protein,
available carbohydrate, total dietary fibre and minerals, and it is believed that these plants
could be used for the nutritional purpose of human being due to their good nutritional
qualities, and adequate protection may be obtained against diseases arising from
malnutrition (Seal et al., 2017).
Undernourishment influences around 900 million individuals on the globe
and more than 2 billion experience the micronutrient deficiencies (Fan et al., 2012). As
indicated by the United Nations Department of Economic and Social Affairs (UN-
DESA), world populace which is at present around 7.2 billion is required to develop to
around 9.6 billion by 2050 and a lot of this development is relied upon to be amassed in
poor underdeveloped nations (DESA, 2013). The anticipated increase in worldwide
21
populace, poor management and lack of resources is expected to enhance food demand
and food insecurity in the coming decades (Rosegrant et al., 2008; Fan et al., 2012). The
cultivation of more food using fewer resources to meet a developing world populace and
guarantee food security becomes a topic that generates a lot of global interest. The latest
meaning of food security was coined at the 2006 World Food Summit: ‘a situation that
exists when all individuals, at all times, have economic, social and physical access to
nutritious, sufficient and safe food that meets their dietary needs and food preferences for
an active and healthy life’ (FAO, 2009).
In spite of the fact that an assortment of wild vegetables might be
accessible in an area, reports have demonstrated that reports have shown that only a few
selected ones are accessible for utilization as food (Hadjichambis et al., 2008). The
capacity of nontraditional vegetables to give the required supplements in human
physiology has been generally reported. They have been shown to keep superior
nutritional potentials than the commercial vegetables (Odhav et al., 2007; Flyman and
Afolayan, 2008; Lewu and Mavengahama, 2010; Kayode, 2012). Despite this, the
abundance of data accessible on the nutritional composition of commercial vegetables
alone is insufficient to fulfil nourishment demands.
It is usually believed that food security requires an interdisciplinary
method to solving, bringing the agriculturalists and nutritionists together (Maunder and
Meaker, 2007; Rocha, 2007; Ingram, 2011; Global Food Security, 2013). According to
Labadarios et al. (2008) the South African diet comprises predominantly of the staple
22
food plants and is deficient in differing qualities and thus prompts micronutrient
insufficiencies. These wild edible vegetables are the good source of nutrient for tribal
population, and in addition well comparable with various commercial vegetables. So, the
cultivation of these wild edible species needs to be adopted in large scale, which will
produce economic benefits for poor farmers (Seal et al., 2017). The World Health
Organization (WHO) prior reported that the utilization of fruits and vegetables is not as
much as half of the prescribed 400 g consumption for each day (WHO/FAO, 2003).
However, some authors (Uusiku et al., 2010; Berti et al., 2014) hypothesized that by
including nontraditional vegetable species in the diets will helps to decrease the
micronutrient deficiencies.
Bvenura and Afolayan (2015) stated that the increased consumption of
nontraditional vegetables will help to reduce the malnutrition and food insecurity.
Moreover, if availability of the traditional and nontraditional vegetables is made
throughout the year will results in food stability. This can be done by encouraging people
to cultivate the nontraditional vegetables in their home gardens during their season and
preserve them for later use in offseason. Bvenura and Afolayan (2015) further reported
that nontraditional vegetables are clearly underutilized although they potentially have a
big role to play in food security. Nontraditional vegetables are required to be revitalized
and widely consumed in daily diets to decease food insecurity. The knowledge about
these species may soon be lost if these species to continuous underappreciated and
neglected.
23
Conserving indigenous knowledge as the key to the current and future use of
nontraditional vegetables
Indigenous information includes knowledge about persistence that is
possessed by native people in their societies and is passed on from one generation to
another (Kaya and Masoga, 2005). This information is found in both urban and rural
societies and deals with problems regarding the survival of the community, protection,
use of the local environment and food security. Indigenized information is found in
various areas i.e. food technology, medicine, conflict resolution, peace building, social
welfare and agriculture (Odora-Hoppers, 2004). The knowledge about nontraditional
vegetables is decreasing which must be documented (Aphane et al., 2003).
Nontraditional vegetables are part of local knowledge and nontraditional
production systems. These vegetables are consumed locally over a number of years, but
did not cultivate (Keller et al., 2004, 2005). Nontraditional vegetables are those edible
plants that are biologically indigenous to an area, while commercial vegetables require
various agricultural related inputs to grow. Indigenized vegetables are local and adapted
to the native environmental conditions (Laker, 2007).
The significance of nontraditional vegetables lies in their high nutritional
quality and their capacity to flourish under unfriendly conditions. Nontraditional
vegetables and nontraditionally crops grow well during dry periods and in regions with
low rainfall. Nontraditional vegetables can survive poor soils, require less inputs,
24
chemical fertilizers (pesticides) and assets during production since they are adapted to the
local environmental conditions (Lephole, 2004; Modi et al., 2006; Van-Vuuren, 2006).
The utilization of nontraditional vegetables is diminishing even in the rural
areas for introduced vegetables and neglected by both researchers and policy makers
which in turn lead to the insufficiency of knowledge about nontraditional vegetables
(Jansen-van-Rensburg et al., 2007). Since documentation on nontraditional vegetables is
rare, elderly individuals remain the most important sources of data. The apprehension
exists that if nothing is done to monitor profitable data on nontraditional vegetables this
data may soon vanish from society, in light of the fact that the adolescent are generally
reluctant to increase such knowledge (Vorster et al., 2007). The exchange of indigenous
information on nontraditional vegetables will guarantee that the accessibility and use of
nontraditional vegetables will be kept up as an essential food sources for asset poor
country groups. Besides, the transfer of the indigenous learning connected with
nontraditional vegetables to the younger generation holds the way to the potential future
utilization of traditional vegetables.
Archiving the utilization of plants by ethnic minorities and tribal
individuals is not just a critical part in understanding and analyzing components of
conventional knowledge, additionally an approach to sustain information at danger of
being lost (De-Boer and Cotingting, 2014). Various research works have shown that
indigenous knowledge of nontraditional vegetables is vanishing in communities (Flyman
and Afolayan, 2008; Musinguzi et al., 2006; Jansen-van-Rensburg et al., 2007; Lwoga et
25
al., 2010). The loss of indigenous information results in less utilization of nontraditional
vegetables, which adds to the lack of diet diversity. This at last translates into food
instability and micronutrient deficiency, particularly among poor communities (Flyman
and Afolayan, 2008). Diverse factors have added to the loss of information about
nontraditional vegetables. These incorporate the introduction of new vegetables,
legislative issues, changes in way of life, habitat loss and the stigma connected with the
utilization of nontraditional vegetables (Keller et al., 2005).
Introduction of new commercial vegetables and Stigma attached to the use of
nontraditional vegetables
The introduction of new conventional vegetables has been referred to as
one of the reasons for the loss of information about nontraditional vegetables. The
conventional vegetables are broadly advanced by agricultural extension and research, in
this way prompting the complete substitution of nontraditional vegetables (Jansen-van-
Rensburg et al., 2007). Recently presented vegetables likewise give financial worth to the
farmers since they are exceptionally prominent and can be effectively promoted. Farmers
are accordingly more excited about the production of these new vegetables than
nontraditional vegetables that are difficult to market to vast (Musinguzi et al., 2006). An
absence of clear custodianship, little comprehension of sustainable management practices
and information of market sector prerequisites, place natural habitats, coupled with poor
social position and economic opportunities for gatherers and lacking institutional
structures and populaces of therapeutic plants at danger (Sher et al., 2010).
26
Negative attitudes towards the utilization of nontraditional vegetables have
additionally been referred to as one reason that adds to the loss of information. In many
ranges, nontraditional vegetables are connected with primitiveness and poverty.
Therefore, many people, particularly the young have stopped utilizing nontraditional
vegetables since they would prefer not to be marked as backwards (Jansen-van-Rensburg
et al., 2007).
Some nutritional challenges of nontraditional vegetables
Nontraditional vegetable plants play an important role in the health of
millions of people’s life in many villages ranging from 75– 80% of the world population,
mainly targeting primary health care in the developing countries because of better
cultural acceptability, compatibility with human body and lesser side effects (Kumar et
al., 2017). The incorporation of nontraditional vegetables into the diet has been ruined by
cultural and social issues in a few communities and a few authors have raised different
concerns over the suitability of these species to supply the required nourishing necessities
in the body. The nearness of antinutrients, for example, oxalate, phytic acid, saponins,
tannins and alkaloids in nontraditional vegetables has raised some serious concerns. In
the human body, oxalate ties to calcium to form calcium oxalate stones that prevent the
assimilation and usage of calcium leading to sicknesses, for example, osteomalacia and
rickets (Ladeji et al., 2004). Tannins can hasten certain proteins by joining with digestive
enzymes in this way making them inaccessible for absorption (Abara, 2003). Phytic acid
consolidates with some crucial components, for example, iron, zinc and phosphorus to
27
frame insoluble salts known as phytate. In Brazil, elevated amounts of tannins were
accounted for in the leaves of Talinum fruticosum (Leite et al., 2009). In spite of the fact
that Lola (2009) reported that some anti-nutrients, for example, tannins and oxalate are
health labile, heating T. fruticosum leaves did not change the composition of these anti-
nutrients. Though, in Nigeria, some common wild vegetables including Amaranthus,
Solanum and Corchorus species were found to contain low levels of these anti-nutrients.
(Agbaire, 2012). Despite the great advances observed in modern medicine in recent
decades, nontraditional vegetable plants still make an important contribution to health
care (Kumar et al., 2017).
In South Africa, Ndlovu and Afolayan (2008) found the leaves of C.
olitorius to contain different levels of phytate when compared with spinach and cabbage.
An investigation of Erythrina Americana in Mexico showed that the eatable flowers
contained noteworthy measures of alkaloids; whereas, these were disposed of by
discarding the water after boiling (Sotelo and Lopez-Garcia, 2007). The mineral content
while comparing with recommended dietary allowance, it reveals that the nontraditional
vegetables are good source of calcium, iron and zinc (Tope et al., 2017). Although some
nontraditional vegetables have been accounted for to contain some antinutrients, others
contain a few phytochemicals, for example, antioxidants that are valuable in human
physiology.
Antioxidant activities have been accounted for in an assortment of some
nontraditional vegetable species from different parts of the world (Afolayan and Jimoh,
2009; van-derWalt et al., 2009; Pereira et al., 2011; Morales et al., 2013; Garcia-Herrera
28
et al., 2014a and 2014b). These reports from different parts of the world demonstrate that
diverse nontraditional vegetables from various geological areas contain shifting measures
of phytochemicals including cancer prevention agents and antinutrients. The behavior of
phytochemicals, particularly antinutrients in nontraditional vegetables is a subject that is
not yet completely comprehended, thus needs more research. A comprehension of the
negative or positive effect nontraditional vegetables have on nutritional absorption in
human physiology will develop reasonable food security techniques.
Bvenura and Afolayan (2015) exhibited that the incorporation of
nontraditional vegetables in the eating routine could go far in handling malnutrition and
food insecurity particularly in children who are the most susceptible. Above all, there is a
need to educate the general population about the significance of nontraditional vegetables
so that their states of mind can change. The false and negative observations
encompassing the utilization of nontraditional vegetables, for example, poverty foods,
foods for women, children and the elderly and additionally drought foods should be
especially changed. The younger generation who are the future caretakers of this
information should be urged to welcome these assets while preservation of the current
species through exploration should be amended. Cultivation of the favored species
particularly those with positive organoleptic and healthful qualities should be supported.
Nutritional and Health Benefit information of nontraditional vegetables
Nontraditional vegetables are excellent sources of nutrients and energy,
besides they provide the bulk of daily calories and around 65% of the protein (Bennett,
29
2016). Interest in nontraditional vegetables has fundamentally expanded in Europe, and
somewhere else, in light of the fact that they give high nutrient levels and potential health
advantages (Garcia-Herrera et al., 2014b). The consumption of nontraditional vegetables
has generally assumed an essential part in supplementing staple farming foods in
numerous nations and their commitment to the Mediterranean diet is very much recorded
(Hadjichambis et al., 2008; Tardio, 2010). A few studies showed the essential role played
by nontraditional species as excellent source of macro and micronutrients in adding to
human dietary prerequisites (Flyman and Afolayan, 2008; Tardio et al., 2011). The
nutritional composition of nontraditional foods indicates that most of these foods are good
sources of carbohydrate, moderate sources of protein, fat, phosphorus, and iron and low sources
of dietary fibre, vitamin D, and calcium. Moreover, they provide substantial amounts of phytate
and smaller amounts of oxalate (Al-Faris, 2017).
Additionally, nontraditional vegetables may have part as functional foods
as they contain physiologically active foods and give health advantages beyond basic
nutrition, indicating potential biological activity of interest for the prevention of several
chronic diseases (Flyman and Afolayan, 2008). Therefore, these nontraditional plants
have been minimal concentrated as foods and are excluded in food composition databases
because of the lack of information on their composition in scientific writings (Garcia-
Herrera et al., 2014b). In this way, many individuals harvest nontraditional vegetables for
their substantial contribution to the diet as healthy components, for example, minerals,
cancer prevention agents and vitamins. In this way, the convention of eating
unconstrained plants is still alive as well as is expanding subsequent to the nontraditional
vegetables are viewed as healthy and natural foods (Pereira et al., 2011; Renna and
30
Gonnella, 2012; Sanchez-Mata et al., 2012). Nontraditional foods can be used in the
prevention and management of obesity, cardiovascular disease and diabetes mellitus.
Country dietary guidelines should take into consideration the nutritive value and health
aspects of these foods and encourage the consumption of healthy traditional foods (Al-
Faris, 2017).
Nontraditional vegetables are an imperative source of phytonutrients that
are fundamental for human body and can be incorporated into numerous vegetable salad
dishes to enrich dietary sources of health promoting compounds (Kaliora et al., 2015;
Kumar et al., 2015). Moreover, the utilization of wild edible nontraditional vegetables
has considerably decreased during the last few decades (Turner et al., 2011; Morales et
al., 2013). The worldwide interest for the supposed "health" or "super-foods" has revived
the market sector requirements for wild palatable species consumed as salad vegetables
and greens, subsequent to their expansion could supplement human eating routine and
supply human body with essential trace elements and vitamins (Barros et al., 2010).
Most of nontraditional edible vegetable species have medicinal property
and can be used to keep people healthy and fit. Further phytochemical and nutraceutical
studies of these edible species may provide better nutritional source. Apart from the
source for food, human also utilize plants for dyes, ornaments and medicines.
Nontraditional edible vegetable is source for nutrition but also possess higher medicinal
property. These nontraditional vegetable plants are grown in forest region without
chemical / fertilizer. Most of nontraditional vegetable are grown naturally without proper
31
cultivation technique in forest area; specifically, during monsoon season and collected by
tribal people. Tribes are part of nature; they fulfill their need through wild resources.
Their knowledge is based upon traditional sources (Seema, 2015).
Nutritional analysis of nontraditional vegetable demonstrates that the
nutritional quality of nontraditional vegetable is comparable and in some cases, they are
superiors to domesticated verities (Seema, 2015). Nontraditional foods have potentially
useful applications in planning normal and therapeutic diets (Al-Faris, 2017). The major
nutritional compounds that are present in nontraditional vegetable plants are
carbohydrates in the form of starch and sugars, protein, lipid, in the form of oil, vitamins,
minerals, etc. Apart from these antioxidants, like ascorbic acid, phenols such as
cholorogenic acid and its polymers are available in plant because of these component, the
wild vegetable most have potential to improve physical as well as mental health, help in
reduce the risk of disease. There is therefore a need to explore the vast varieties of
nontraditional vegetables as food by man (Edogbanya, 2016).
Factors affecting nutrient content of vegetables
The biosynthesis and concentration of nutrients differ generally among
nontraditional vegetables and on the effects of hereditary and environmental factors
(temperature and light), harvest practices, growing conditions and postharvest techniques
(Rouphael et al., 2012). Light also plays an important part in operating photosynthetic
and phytochemical activities (Bian et al., 2015) as the phytochemical synthesis and
32
accumulation in plants is highly related with photosynthates (Wu et al., 2007). Hence
therefore, to increase the phytochemical accumulation, the presence of optimal light is
very important (Bian et al., 2015). Post-harvest losses and quality deterioration of
vegetables are mostly caused by pests, microbial infection, during ripening and
environmental status (Idah et al., 2007; Olayemi et al., 2010). It occurs through all or at
least one of post-harvest activities such as harvesting, handling, storing, processing,
packaging, transporting and marketing (Mrema and Rolle, 2002).
The shelf life of vegetables is influenced by various means, for example,
growing strategies, post-harvest processes, processing and storage conditions. Among
these variables, the stage of ripeness at the season of harvest is one of the most important,
as it influences both the shelf life and the eating value of fresh cut vegetables and foods.
Specifically, fresh cut vegetables are harder to protect than other less processed items
since some of them must be totally ripened before processing (Gorny et al., 2000).
Effect of processing methods on nutrient loss
Traditional and nontraditional vegetables are compared by many authors
and found the later more nutritious (Odhav et al., 2007; Afolayan and Jimoh, 2009). The
processing of vegetables, for example, drying and cooking cannot be without impact on
their nutritional attributes. Cooking brings both chemical and physical changes to food
(Rehman et al., 2003). Additionally, food additives further change the nutritious
composition of vegetables. It is basic practice to utilize additives, for example, flavors
33
and spices to upgrade the taste of nontraditional vegetables in this way altering the
original nutritional state of the vegetables. Different processing techniques would
subsequently affect contrastingly on different particular nutrients. In Pakistan, it was
found that boiling decreased the fiber, fat and protein compositions. Ching (2010)
reported in his report that cooking these nontraditional vegetables for long at high
temperatures decreased greatly antinutrients, antioxidants and micronutrients. In his
study, stir frying declined phytate, oxalate, Zn, Fe, Mg and Ca whereas boiling essentially
decreased protein, fat and fiber contents.
Effect of cooking on vegetable processing
Ilelaboye et al. (2013) stated that blanching a variety of nontraditional
vegetables declined their Zn, Cu, Mn, Fe, Mg, Na, K and P contents while cooking the
unblanched samples enhanced the same minerals. Reports have demonstrated that
cooking blanched samples significantly decreased nitrite, nitrate, cyanide, tannin,
saponins, oxalate and phytate while the raw samples contained essentially large amounts
of these antinutrients. At the Virginia State University, raw samples of Urtica dioica
contained large quantities of vitamin A, vitamin C, protien, sugars, fiber and fats (Rutto
et al., 2013). While some nontraditional vegetables, for example, S. oleraceus can be
eaten raw as salads, some should be cooked before intake, for instance S. nigrum and
Urticaurens among others.
34
The nutritional composition of nontraditional vegetables differs after
introduction to heat subsequently; there is a need to treat each vegetable as a unique food.
In South Africa, the majority of nontraditional vegetables are cooked by boiling while
bicarbonate of pop, groundnuts, onions and tomatoes are incorporated as added
substances to upgrade the taste (Nesamvuni et al., 2001). This further increases the
nutritional value of the nontraditional vegetables and subsequently brings down
malnutrition ratio. Presenting nontraditional vegetables to cooking may lessen some
amount of nutrients yet cooking is utilized to upgrade their organoleptic attributes in this
way enhancing their adequacy and part in food security (Subhasree et al., 2009).
Cooking can be performed in different ways at the same time, for
nontraditional vegetables, most basic are microwaving, boiling and steaming. These
cooking procedures would bring about various changes in chemical composition and
physical qualities of the vegetables (Zhang and Hamauzu, 2004). Literature on the
impacts of cooking on the antioxidants in vegetables has been uncertain. There are
reports showing an upgrade or no change in antioxidants activity of vegetables (Turkman
et al., 2005) while others have shown a decline in antioxidant content after cooking
(Zhang and Hamazu, 2004). The diversity and presence of phytochemicals in
nontraditional vegetables are essential components for human wellbeing. Since a
substantial part of ingested nontraditional vegetables are generally thermally handled
before consumption, it is additionally important to investigate how the processing
influences the levels of these compounds (Volden et al., 2009).
35
Processing of nontraditional vegetables for consumption exposes the
phytochemicals present to detrimental factors that may lead to changes in their health
related quality. For instance, wet-thermal treatment causes denaturation of enzymes that
can catalyze breakdown of phytochemicals and nutrients. Then again, processing by heat
can bring about decrease of constituents by leaching or due to thermal destruction
(Rungapamestry et al., 2007). Turkmen et al. (2005) showed that distinctive cooking
strategies (microwaving, steaming and boiling) led to the reduction in phenolics from
leek, peas and squash. Watchtel-Galor et al. (2008) found that microwaving and steaming
brings losses in the total phenolic content of cabbage, choy-total and broccoli while
steaming showed less reduction as compared to microwaved samples. Similarly, Volden
et al. (2009) reported the loss of phytochemicals up to 19% in steamed cauliflower.
It is notable that handling of vegetables promotes a faster microbial
degradation, biochemical changes and physiological deterioration of the item even when
just slight preparing operations can be used (O’Beirne and Francis, 2003), which may
bring about degradation of the flavor, texture and color (Varoquaux and Wiley, 1994).
While traditional food processing strategies broaden the shelf life of vegetables and
fruits, the minimal processing to which fresh cut vegetables and fruits are subjected
renders items exceedingly perishable, requiring chilled capacity to guarantee a reasonable
shelf life (Garcia and Barret, 2002).
Frying is a typical prominent procedure used throughout the world to
generate products with good sensory and organoleptic attributes. In tropical nations, fried
items comprise for the most part of starchy foods (cassava, plantain, potatoes etc) which
36
are characterized by a high initial water content (60-80%) and low nutrient content. The
product during frying undergoes two correlated mass transfers i.e. oil uptake and water
loss. During broiling, the item experiences two associated mass exchanges: water loss
and oil uptake. The dietary value of last product is thus affected by the nature of the oil
used for frying. Since, frying oils differ from each other on the basis of fatty acid content
(saturated and unsaturated) and fat soluble nutrient (sterols, tocols, carotenoids and so
forth). Firstly, the degradation (oxidation or thermal) of fatty acids (mainly unsaturated)
and micronutrients is activated by the high temperatures involved during frying (Valdes
and Garcia, 2006).
The frying oil is used several times (10-15) before renewing and it must be
taken into account to limit the loss of nutrients in order to guarantee the economic and
nutritional sustainability of the process. Furthermore, an uncontrolled frying technique
(temperature more than 180°C, an excessive number of frying baths, inappropriate oil,
and so on.) can lead to the formation of lethal compounds in the final product
(acrylamide) or in the oil (oxidized triglycerides) (Bassama et al., 2012). At last, from a
dietetic point of view, fried products might be attractive or not and may contain varying
proportions of saturated fats. Every one of these viewpoints has incited concentrates on
enhancing the nutritional quality of final product by controlling the frying procedures.
The principle "degrees of freedom" for control of the nutritional value of an item during
frying was the temperature. However, decreasing the frying temperature (120-130°C)
resulted in reduced oil degradation and loss of nutrients as well. Indeed, unsaturated
37
(non-refined) oils bear interesting nutrients could be used with good frying practices
(Achir et al., 2010).
It is realized that cooking impels huge changes in chemical composition,
influencing the bio-accessibility and the concentration of nutrients, for example,
polyphenols, carotenoids and vitamin C (Pellegrini et al., 2010). Mazzeo et al. (2015)
reported that both steaming and boiling strategies could influence nutritional properties of
frozen vegetables in an alternate way.
Effect of drying methods on nutrient content
The fresh vegetables and fruits due to their high moisture content (upto
80%) are highly perishable and can deteriorate within short time if improperly handled
(Orsat et al., 2006). Drying is the procedure that involves the removal of water to stop or
reduce the growth of microbial contamination and enzymatic browning (Argyropoulos et
al., 2011; Kurozawa et al., 2012) which in turn help in preserving the nutritional value
and sensorial characteristics of the foods (Aguilera, 2003). There is the rapid growth rates
(3.3%) observed in the market value of dehydrated vegetables and fruits throughout the
world (Zhang et al., 2006). Drying of foods is the most common and oldest technique
involving the controlled transfer of heat (Mujumdar and Passos, 2000). Vegetables and
fruits are commonly dehydrated to reduce transport weight, minimize packaging
requirements, to enhance storage ability and to extend the shelf life (Ahmed, 2011). The
common methods used for drying the foods involve sun or hot air drying. Since solar
drying is the slow process which can be affected by birds, insects and rodent’s
38
infestation, Weather uncertainties, windblown debris high humidity (rain) and haze
(Ringeisen et al., 2013). Drying is amongst the most widely recognized food processing
strategies that can be utilized to extend the shelf life and to accomplish the required
qualities of a food items. Decreasing the water activity (aw) of food by means of this
procedure can reduce deterioration from microbial activity and chemical reactions
(Chiewchan et al., 2010).
According to Vorster et al. (2007) that preservation of nontraditional
vegetables helps to ensure food accessibility throughout the year, but Flyman and
Afolayan (2008) stated that it affects the nutritional quality of the foods like many other
processing treatments. Vorster et al. (2007) further surveyed that all the Xhosa
households dried vegetables without blanching them first which in turn largely affected
the nutritional content of vegetables. Flyman and Afolayan (2008) reported that when
vegetables are dried without prior blanching in direct sunlight leads to the destruction of
nutrients. Hassan et al. (2007) reported that the solar drying is hygienic, faster and have
no effect on the nutrients.
Sensory evaluation
The desireability of any food product is depend on its quality which can be
determined by objective and sensory methodologies. The psychometric, sensory,
organoleptic and subjective tests are taken by human organs to check the quality of food
(Srilakshmi, 1996). The senses used in sensory evaluation include tactile, taste, odor,
39
temperature, etc. Scientific methods of sensory analysis of foods are becoming
increasingly important in assessing the acceptability of food products (Jellinek, 1985).
Importance of sensory evaluation
The sophisticated food quality measuring instruments including nuclear
magnetic resonance spectrometers, gas chromatography, mass spectrometers, IR and UV
spectrophotometers, etc has increased the importance of sensory analysis. The optimal
information be obtained by the coordination of instrumental and sensory analysis. Even at
the limit of the instrumental sensitivity, e.g. where no signal appears, our biological
detector (our senses) may still perceive an odor, taste, etc. Furthermore, the instruments
will only analyze single components, whereas our senses give us a total impression of
flavor, odor, temperature and tactile components (Jellinek, 1985).
Conclusions
The literature review suggests that the awareness campaigns can help to
aware people’s knowledge about nutritional qualities of nontraditional vegetables.
Moreover, the loss of nurients occur during different cooking processes, hence therefore
there is a dire need to develop such cooking methodologies which ensure minimal loss of
nutrients in cooked vegetable. This will promote the confidence of users and general
utilization of nontraditional vegetables. It was also revealed that there is a lack of cooking
methods which in turn cause the taste of nontraditional vegetables less appealing and
boring. This would increase the interest of people to the consumption of nontraditional
vegetables which in turn also produce diet diversity for human being.
40
CHAPTER-III
MATERIALS AND METHODS
This section comprises the methodology used in the present research
study, i.e. location or description of the study area, type of the data, sources of the data,
sampling methods, data collection methods and analysis of collected samples.
Purpose of the study
The purpose of this study was to examine how rural residents of the lower
Sindh navigate their nutrition environment to obtain the foods they eat. The research was
aimed at selecting the inhabitant’s own perceptions about consumption and nutritional
quality of the selected nontraditional vegetables were explored. The selected
nontraditional vegetables were then also compared with the nutritional values of standard
commercial vegetable (Figure 1).
Description of research area
Perspective/ Status of vegetable production in Sindh
Agriculture is the backbone of the Pakistan’s economy, its development
and progress is therefore linked directly to the agriculture sector contributing 25% in the
Gross Domestic Product (GDP) of the Pakistan (GOP, 2011-12).
41
Figure 1. Schematic representation of the methodology used in the present study
NUTRITIONAL ASSESSMENT OF SOME NEGLECTED AND UNDERUTILIZED
VEGETABLES WILDLY GROWN IN SINDH
Survey of Mirpurkhas district
Collection, weight determination and transportation of nontraditional
vegetable samples
Identification of nontraitional vegetables grown in Mirpurkhas
district of Sindh province
Sample treatment and percentage non-edible and edible portions of
selected vegetables
Edible portion Non-Edible portion
Discarded
Thermally Dehydrated Shade Dried Fresh
(control)
Boiled
Nutritional Analysis
Statistical Analysis of obtained data
Cooked Curry
Data Analysis
Fresh
(control)
Chlorophyll content
Statistical Analysis
Curry
Sensory Analysis
Statistical Analysis
Fresh (raw)
42
On the basis of population and agriculture input, Sindh is regarded as
second biggest province of Pakistan, situated on the lower bank of river Indus. Sindh
represents about 23% (32 million) of the total population of Pakistan and on geographical
basis, it covers 18% of the area i.e. 140935 Km2
(14.09 million hectares). Sindh has 40%
of the total arable land with 5.88 million cultivated areas and 2.39 million hectares of
sown area. Hence, there are about 3.10 million hectares of total cultivated area, of which
0.71 million hectares of the land are used more than once for sowing purpose. The
climate of Sindh is an overall arid zone with rare monsoon rains that come in the rotation
of 4 to 5 years, leaving the canals as the only source for irrigating the crops. The hottest
months of the Sindh province are recorded from May to July i.e. above 40 ᴼC with
occasional frost (Development statistics of Sindh, 2011).
District Mirpurkhas
The description of selected district is according to agricultural statistics of
Sindh (Development statistics of Sindh, 2011) as shown in Figure 2.
The district Mirpurkhas is situated at the South-East corner of the
province. It lies from 25-9' to 29-17' North latitude and 69-3' to 69-26' East longitude.
It is bounded on the North by the district of Sanghar, in the East by the newly created
district Umerkot bordering the Bermet/Marwar and Jaisalmir districts of India, on the
West by the district of Hyderabad and in the West-South by the district Badin, in the
south by the district Thar bordering the Rann of Kutch. The Mirpurkhas District
comprises 2991 km2 (2.10%) of the total geographical area of Sindh, with the total
population of 1.4 million souls accounted in 2012. The highest and lowest recorded
43
temperatures of the district are 41C and 9 C, respectively. June and September are the
monsoon months and there is insignificant rainfall recorded in the winter season
(Wikipedia).
Figure 2. Map showing selected district of Sindh Province, Pakistan
44
Survey of Mirpurkhas district
Identification of wild vegetables grown in Mirpurkhas district of Sindh province
The questionnaire survey methodology was used to collect the data on the
utilization and consumption of nontraditional and commercial vegetables in culturally
and ecologically diverse area, Mirpurkhas of Sindh province, Pakistan in 2014.
All relevant farmers were informed at first about the study, its objectives
and how the study would be conducted then a consent letter (Appendix XLIII) was signed
by each participant farmer after explanation in Sindhi (local language) showing that they
were agreed to participate in this research project conducted by PhD scholar and her
consulted supervisor / advisor of IFST, SAU, Tandojam.
Each respondent agreed that their participation was strictly voluntary. The
farmer’s response to every question was written in the structured questionnaire form
(Appendix XLIV), recorded and kept for in a locked file cabinet. The questions were at
first explained in Sindhi (Local language) to each participant and the information was
documented. The process was very extractive in the beginning, but as trust and respect
between community members and research team developed participation grew.
Design of the questionnaire
The questionnaire was designed according to the problem tree methods
proposed by Fink (1995), with mainly closed questions that were based on the opinions
of key informants. The information that was gathered through these activities was used to
help develop the questionnaire. A problem tree was developed that addressed all of the
45
objectives that needed to be answered by questionnaire. These objectives were broken
down into questions that needed to be answered to address these specific objectives. The
questions were discussed with experts (sociologist, extension, personnel and researchers)
to ensure that they measured the objectives accurately. The questions were very specific
to minimize possible misunderstanding between enumerator and respondent. Open
questions were used in areas where answers were expected to be variable. The local
experts, villagers and reference books on local plants were extensively used as sources
for plant identification and distribution. Census data were used to help understand the
community and population better. As early as 1937, Sletto found that respondents would
rather agree as disagree (Mounton and Marais, 1993), thus such questions were avoided.
The question asked of respondents to describe certain aspects and the enumerators ticked
off what was mentioned.
Sample size or sampling of farmers from Mirpurkhas district of Sindh
Systematic sampling (Fink, 2003) was used to identify the respondents in
the selected District, as sampling frames were difficult to obtain and not very complete.
The farmers were randomly selected for the face to face interviews. Determination of
minimum sample size of 100 respondents district Mirpurkhas was done according to the
method of Bartlett et al. (2001), so as to achieve a maximum error of 5 % at a 95 %
confidence level. In this way every element in the population has the same chance of
being selected. Therefore, sampling was done “without replacement”.
46
Methods of data analyses for survey
The data of survey was coded and analyzed by using descriptive statistics
module of SPSS-16 for presenting in frequencies and percentage counts.
Selected agricultural locations and vegetable production
District Mirpurkhas was surveyed in this study. The vegetables that were
focused to be cultivated were spinach whereas there were other vegetables too, which
were not cultivated and even without any agricultural input, i.e. Amaranthus, Horse
radish tree flowers and Lambs quarter. The Gram crop is cultivated as pulse crop purpose
but its leaves are consumed in rural villages as nontraditional vegetable. These
nontraditional vegetables are considered as weeds growing in the fields without any labor
and farm inputs. At present these nontraditional vegetables are discarded by the growers
because of lack of awareness. These vegetables have also a great importance because
these grow in commercial crops (such as sugarcane, cotton, wheat, rice, etc).
Nontraditional vegetable specimens were recognized with the help of flora of Pakistan by
using the Nomenclature of Nasir and Ali (2005) (Table 1, Figure 3).
47
Table 1. Enumeration of selected vegetables
Plant Name English
name
Local
name Family Position
Parts
Used Status
Amaranthus
viridis L. Amaranthus Mariro Amaranthaceae
Leafy
vegetable Leaves Wild
Cicer
arietinum L. Gram Channa Fabaceae
Leafy
vegetable Leaves
Cultivated as
pulse crop,
leaves under-
utilized as
vegetable
Chenopodium
album L.
Lambs
quarter Jhil Chenopodiaceae
Leafy
vegetable Leaves Wild
Moringa
oleifera L
Horse radish
tree flowers Suhanjhro Moringaceae
Flower
vegetable Flowers Wild
Spinasia
oleraceae L. Spinach Palak Chenopodiaceae
Leafy
vegetable Leaves Cultivated
48
English name: Amaranthus English name: Gram leaves
English name: Horse radish tree flowers English name: Lambs quarter
English name: Spinach
Figure 3. Pictorial view of selected vegetables
49
Analysis of uncooked vegetables
Collection of vegetable samples
Sampling was conducted according to the international standard guideline
(SAC, 2008). Spinach, Horse radish tree flowers, Gram leaves and Lambs quarter were
collected in January, 2014; whereas, Amaranthus was collected in the months of July-
August, 2014 from Mirpurkhas district. The vegetables (Spinach, Amaranthus, Gram
leaves and Lambs quarter) were collected by cutting the stem approximately 3 cm from
the soil surface. Whereas, the Horse radish tree flowers were plucked from tree with care.
At each sample location, fresh, non- infested and un-damaged vegetable samples were
collected from three different sites to provide replicate samples of each plant.
Weight determination and transportation of veteable samples
The weight of the vegetables was obtained by placing the vegetables on
pre-weighed pan digital top loading balance and the reading was noted carefully. Sample
size for each vegetable was at least 10 kg and was taken among commodities considering
high consumption rate. Samples were transferred aseptically into sterile Nasco Easy-to-
Close Whirl-Pak sample bags (Fisher Scientific) without washing. Sample bags were
marked on the exterior surface with the following information: product type, sample
number, sample location, date of collection and placed in an ice chest box and transported
to the laboratory of IFST, SAU, Tandojam on the same day. Samples were stored in
refrigerator at 4°C for 1-2 days until traditionally processed.
50
Treatment of uncooked vegetable samples
The edible parts were separated from their respective non-edible parts.
The samples were washed, removed nonedible portion, cut according to the nature of
vegetable. Edible parts of the plants are those which intended for cooking or eating as
raw, for example leaves, shoots, flowers, etc., whereas non-edible parts of the plants are
those which we do not eat such as seeds, stem, roots etc. Edible parts were washed with
mild rubbing under running tap water for 25-30 seconds to remove unwanted materials
(dirt and debris) and placed in a hung strainer in the air to drain away extra water. The
remaining moisture was evaporated by spreading samples on a stainless steel tray at
room temperature for 30 minutes. Blanching treatment was avoided due to increased
losses of nutrients as well as unwanted color change (Arya et al., 1979; Baloch et al.,
1997).
Non-edible and edible portions were weighed and the percentage of non-
edible portion (skin, seeds, etc.) of selected vegetables was calculated by the following
formula:
The percentage of edible portion of selected vegetable was calculated by the formula
For each selected vegetable the percentage of non-edible and edible portions are given in
the Table 2.
51
Table 2. Percentage non-edible and edible parts of the selected vegetables
Vegetable names Total
weight
Weight
of edible
part
Weight of
non-
edible
part
Percentage
edible
portion
Percentage
non-edible
portion
Spinach (Spinacia
oleracea)
10 kg 6.9 kg 3.1 kg 69% 31%
Amaranthus
(Amaranth Virdis)
10 kg 6.7 kg 3.3 kg 67% 33%
Horse radish tree
flowers (Moringa
oleifera)
10 kg 6.3 kg 3.7 kg 63% 37%
Lambs quarter
(Chenopodium
album)
10 kg 6.8 kg 3.2 kg 68% 32%
Gram leaves (Cicer
arietinum)
10 kg 6.1 kg 3.9 kg 61% 39%
Treatment for fresh uncooked samples (Control)
The first set of all the vegetables was cut into smaller pieces with a sharp
stainless steel knife and packed in properly labeled polyethylene bags and kept in a deep
freezer at -20± 1°C until analyses was performed within twenty four hours.
Sample preparation for processing methods
Six kilograms (6 kg) of each vegetable sample were separated for further
analyses. The samples were divided into five (5) sets. 1st set was (1 kg) and packed in
properly labeled polyethylene bags to serve as control. 2nd
set (1 kg for each) was
subjected to boiling. The boiled sample was divided into two equal portions, out of which
one portion was packed as it is while other was subjected to cooking with standard
52
ingredients. The 3rd
and 4th
set was subjected to thermal dehydration and shade drying.
The details of each set treatment are given below:
Treatment for fresh samples (Control)
The first set of all the vegetables was cut into smaller pieces with a sharp
stainless steel knife and packed in properly labeled polyethylene bags and kept in a deep
freezer at -20± 1°C until analyses was performed within twenty four hours.
Treatment for boiled samples
The second set of vegetable samples was cut into evenly sized chunks.
The water was added to boiling pan and allowed to boil before addition of vegetables.
The amount of water was kept minimum just to cover the vegetable samples in order to
reduce the nutrient loss in water. The vegetable samples were boiled for 5 minutes and
then the water was drained. The samples were allowed to cool at room temperature and
then packed properly in pre-labelled polythene bags. The packed samples were then
placed in deep freezer at -20± 1°C until analyses.
Treatment for making vegetable powder
The 3rd
and 4th
set of all the vegetables was subjected to thermal
dehydration and shade drying. The leaves and flowers were kept in a butter paper
envelope and dried in an oven (Model: FPM-05-0401, GLSC equipment’s Pakistan) at
55ºC for 24 hours (Abuye et al., 2003). Similarly, for shade drying the samples were kept
on stainless steel tray lined with butter paper at room temperature for 24 hours. The dried
53
samples were pounded into fine powder using a laboratory pestle and mortar. The powder
obtained was passed through 2.0 mm sieve prior to analyses (Fasakin, 2004) and kept in
airtight pre-washed sterilized glass bottles in dry and cool place until nutritional analyses.
Treatment for vegetable cooking
The equal half of boiled vegetable sample was subjected to cooking with
standard ingredients, allowed to cool at room temperature and displayed for sensory
evaluation.
Development of different cooking methods for selected vegetables and their
organoleptic evaluation
Cooking of food is the use of heat to bring about desirable changes in
foods since it improves the flavor of the cooked food to enhance the human palate
(Mudambi and Rajagopal, 1981). The standard cooking methodology used for each
vegetable is given in the Table 3. The saucepan was placed on medium flame with canola
oil. The sliced onions were added and stirred till golden brown color appeared. Next the
chopped garlic, tomatoes with all other ingredients were added and stirred for 30 seconds.
The edible portion of vegetable samples (leaves cut into chunks and flowers) were then
added to the saucepan and stirred for 5 minutes. The vegetable samples were left till
water evaporated at low flame. The cooked vegetable was stirred and taken out into
prewashed bowl.
54
Table 3. Cooking methodology of amaranthus, lambs quarter, gram leaves, horse
radish tree flowers and spinach
Ingredients
Amaranthus Lambs
quarter
Gram
leaves Spinach
Horse radish
tree flowers
Weight (g)
Total vegetable 500 500 500 500 500
Salt 2 2 2 2 3
Red chili powder 2 2 2 2 3
Turmeric powder 0.5 0.5 0.5 0.5 0.5
Onion (chopped) 10 10 10 10 10
Tomato 20 20 20 20 20
Garlic 5 5 5 5 5
Chilli green 10 10 10 10 10
Oil 30 ml 30 ml 30 ml 30 ml 30 ml
Final product 511 519 513 508 570
No of servings 4 persons 4 persons 4 persons 4 persons 5 persons
Sensory evaluation of cooked and uncooked vegetables
Coding of vegetable samples
All the dishes filled with prepared vegetables were coded at first in order
to know the liking of experts. It would also help to know that the prepared nontraditonal
vegetables are acceptable as a food or not at all. Therefore, all the cooked and uncooked
nontraditional and local vegetables were served with the coded form as shown in Table 4.
55
Table 4. Coding of nontraditional and commercial vegetables
Coding pattern Cooked vegetables (Common names)
A Amaranthus
B Horse radish tree flowers
C Lambs quarter
D Gram leaves
E Spinach
Coding pattern Uncooked vegetables (Common names)
F Amaranthus
G Horse radish tree flowers
H Lambs quarter
I Gram leaves
J Spinach
Selection of trained panel of judges for sensory evaluation
The uncooked and prepared recipes of all nontraditional and local
vegetables were subjected to sensory evaluation. The evaluation was done by a trained
panel consisting of ten members using five point hedonic scales. The panel was given a
sufficient amount of coded samples at room temperature in a white glass bowl of the
same size and shape. The evaluation was carried out in a quiet, odor-free room
maintaining ideal conditions for testing. Each panelist was given a proforma of cooked
and uncooked vegetables (Appendix XLV and XLVI) and asked to evaluate the samples
for different attributes viz. color, odor, texture, taste and overall acceptability. Following
measures were taken to reduce the potential bias:
The dishes were presented on separate tables to look attractive.
56
Panels of judges were requested not to communicate during assessment and were
positioned so that they could not see reactions of each other.
All the judges were asked to drink a sip of water after tasting each prepared dish
to minimize the influence of previously tasted dish on another dish.
All the dishes were coded and kept confidential.
Determination of nutritional characteristics of uncooked and cooked vegetables
Nutrients are needed for body building, energy, maintenance and/or
regulation of body processes therefore, it is necessary to determine the nutritional
characteristics of food which will be consumed as a part of the meal. The food is then
sealed hermetically in an oxygen and moisture proof, easy close bags and stored at -20 °C
until nutritional analyses.
The fresh cut (control), powdered (thermally dehydrated and shade dried),
boiled and curry samples were subjected for the nutrient analyses as follows:
Proximate analysis
The fresh, boiled, curry, thermally dehydrated (powdered) and shade dried
(powdered) samples were extracted and processed for proximate analyses (Proteins,
crude fibers, fats, carbohydrates, ash and moisture) according to the standard methods.
57
Percentage moisture content (%)
The AOAC (2000) method was used to determine moisture content of the
samples. The 5g sample was taken in a pre-weighed, flat-bottom dish and placed in an oven
at 60± 2°C for 24 hours. The sample was then on the next day placed in a desiccator for 1
hour and then the loss in weight was recorded and results were obtained by using the
formula given below:
Percentage ash content (%)
The procedure of AOAC (2000) was followed to determine ash content (%).
The sample of 5g was taken in pre-weighed silica crucible and placed in a muffle furnace at
550 °C for 5 hours or until grayish-white ash appears. Next, the sample was cooled in a
desiccator for1 hour and weighed. To confirm the result the crucible was re-heated for 1
more hour, cooled and weighed. The procedure was repeated till a constant weight was
achieved. The ash weight was calculated with the given formula:
Pecentage fat content (%)
The weight of the extraction flask of soxhlet apparatus was noted. The
sample of 5 g was taken in a thimble with the help of a pair of tongs and closed it with fat
free cotton swab. The thimble was then placed carefully in the extraction unit. About 150
58
ml of the petroleum ether was added to the extraction flask and fitted with condenser
connected to the tap water for cooling. The soxhlation assembly was then fitted with the
stand over a hot plate and heated at 60 °C for six hours (AOAC, 2000).
Next, the flask was removed and transferred to the desiccator to cool for
30 minutes. The ether was evaporated by rotavapor and the flask containing fat was
weighed and reading was noted carefully and calculated by the given formula:
Where, W1 = empty flask weight
W2 = weight of the flask containing fat
W3 = sample weight
Percentage crude fiber (%)
The sample for crude fiber anysis was taken after removal of fat in
soxhlation and was estimated by acid and alkali method (Khalil and Durrani, 1990). 2 g
of the sample was placed in a beaker and 100 ml of HCl (2.5%) was added. The mixture
was boiled with stirring for about half an hour. The sample was then allowed to cool and
filtered with a linen cloth into a conical flask. The filtrate was rinsed with the warm
distilled water. The residue left was then added to another beaker for alkali digestion. The
fiber residues were again digested with 100 ml of 2.5% of caustic soda in a similar way
as it was done in acid digestion. The sample was dried overnight. The fiber residues were
then carefully transferred to the pre-weighed dry crucible. The crucible was then placed
in a muffle furnace at 550 °C for 5 hours till a grayish-white ash formed. Next, the
59
crucible was transferred to the desiccator, allowed to cool and weighed again. The loss in
weight of the dried residues upon ignition was noted as amount of crude fiber. Percentage
of crude fiber was calculated as follows:
Where, W2 = weight of the ash
W1 = weight of the sample
Percentage protein content (%)
Micro-Kjeldhl method of AOAC (1990) was used to determine the nitrogen
content. For this, 2g of sample was placed in a micro Kjeldahl flask and added 20ml of
concentrated H2SO4 (sulfuric acid), 10 g of NaSo4 (sodium sulfate) and 1 g of CuSo4
(copper sulfate). The mixture was warmed slightly at first and then increased when frothing
reduced from 8 hours till a bluish green translucent solution appeared and organic matter
was oxidized to inorganic form. The hot plate turned off when the required digestion of the
material was obtained. The digested material was allowed to cool and filtered with
whatman filter No. 42 paper and taken into a volumetric flask and made the final volume
up to 250 ml.
The distillation of the digest sample was performed by Markam still distilled
apparatus (Khalil and Durrani, 1990). About 5 ml of the digest samples along with 5 ml of
40% caustic soda (NaOH) solution and a few drops of distilled water was added through
the distillation tube into the flask. The distillation continued for 15-20 minutes and the
ammonia gas (NH3) produce was kept in a flask along with 20 ml boric acid (4%) and 3-5
60
drops of methyl red indicator. The distillation was stopped when the pink color in the flask
converted into yellow. The flask was removed and titrated against the 0.1M H2SO4 till pink
color appeared. The titrated value at which pink color appeared was recorded and nitrogen
content was calculated by the following formula:
Where, 100 = Conversion to percent
0.0014 = Constant which means that 0.0014 is liberated by 1ml of 0.100 H2SO4
6.25 = Factor for vegetables
Percentage carbohydrate content (%)
The difference method was applied to calculate the carbohydrate (%)
(AOAC, 1990).
Organic acids (%)
Organic acids were determined by calculating titratable acidity of the
sample. The titratable acidity was evaluated due to the method of AOAC (2000). 10 gram
sample was mashed into pestle and mortar with 30 ml distilled water. The sample was
stirred and filtered through whatman filter paper No.4. The 10 ml of filtred sample were
61
taken into a prewashed conical flask and added 3-5 drops of phenolphthalein. Next the
sample was titrated against 0.1 N NaOH (sodium hydroxide).
Equivalent weight of citric acid = 70 g
Equivalent weight of tartaric acid = 75 g
Equivalent weight of oxalic acid = 45 g
Equivalent weight of acetic acid = 60 g
Mineral analysis (mg 100g-1
)
Sample preparation/digestion and analyses of mineral elements
100 ppm stock solution of the micro minerals such as copper (cu),
iron (Fe), zinc (Zn), magnese (Mn) and macro minerals, including magnesium
(Mg), calcium (Ca), potassium (K) and sodium (Na) were prepared. Perchloric-acid
digestion method with a slight modification was used for elemental analyses (Allen,
1974). 0.25 g sample was added to 6.5 ml of mixed acid solution, i.e. nitric acid,
sulfuric acid and perchloric acid (5:1:0.1) and digested in a flask (50 ml) on a
hot plate in a fume hood till the digestion was completed. Digested samples were
allowed to cool, fil t ered (Whatmann No. 42) and transferred in a 20 ml volumetric
flask, by rising volume with 0.2N HNO3. The sample was then collected into
prewashed, sterile, acid friendly plastic bottle and the concentration of each element
was determined on Shimadzu AA-670 atomic absorption spectrophotometer. The
atomic absorption instrument was calibrated intermittently during analyses and the
62
minerals of the given sample were estimated. The blank solutions were used in between
each run in order to minimize the interferences. Concentration of each element was
calculated by using a formula:
Where;
A=Total volume of extract (ml)
W=Weight of dry plant
Vitamin assay
Chemicals and Reagents
HPLC-grade solvents were used for analyses. Acetonitrile and methanol
were procured from Lab-Scan, USA. The water used for HPLC and sampling was
prepared with Millipore, Molsheim (France). All vitamin standards were of HPLC grade
and were obtained from Sigma Chemical Company.
Standard preparation
The stock solution of vitamins was prepared before vitamin analyses in
order to achieve accuracy of the sample results. The stock solutions of respective
standards of water soluble vitamins were prepared as follows:
Vitamin B1 (Thiamine): Dissolve 25 ml of distilled water with 26.7 mg of thiamine
hydrochloride.
Vitamin B2 (riboflavin): Dissolve 100 ml of extraction solution with 6.9 mg of
riboflavin (extraction solution has limit to dissolve 7 mg of riboflavin).
63
Vitamin B3 (Nicotinamide): Dissolve 25 ml of double distilled water with 41.5 mg of
nicotinamide.
Vitamin β-carotene: weigh 1.0 mg of β-carotene into a 25 ml volumetric flask,
dissolve with hexane until all β-carotene is dissolve, and then dilutes to mark with
hexane.
Vitamin C: add 100 mg of ascorbic acid in 100 ml volumetric flask and make the
final volume with 3% (50:50) solution of metaphosphoric acid (0.3 M) and acetic acid
(1.4 M).
All the stock solutions prepared were stored in dark at -20 ∘C. The
standard curves from the peak areas were prepared by injecting the 20 µl of standard
solution (Aslam et al., 2008).
Determination of vitamin B1 and B2 (mg 100g-1
)
Five gram sample was taken into a conical flask with 0.1N HCl, covered
with aluminum foil, mixed and placed in autoclave (121°C) for 30min. Sample was taken
out from autoclave and then cooled to below room temperature. The solution was
adjusted to pH 4.0 with 4.0 M sodium acetate buffer (pH 6.1) and then added 5 ml of
10% takadiastase solution, flask caped, mixed and placed in a water bath (45-50 °C) for 4
hours with time to time mixing. Flasks were allowed to cool and the solution was
transferred to the volumetric flask (100 ml) making the final volume with deionized
water. The solution was filtered through filtration assembly (0.45μm sized pores) into
amber glass bottle for HPLC analysis (Fernando and Murphy, 1990).
64
Determination of vitamin B3 (mg 100g-1
)
One gram of sample was taken into a centrifuge tube with 0.75g Ca (OH)2
and 20 ml of de-ionized water, mixed well and placed into preheated autoclave (121 °C)
for 2 hours. The sample was taken out, allowed to cool at room temperature, transferred
to the volumetric flask (50 ml) and made the final volume with deionized water. The
digested sample was then centrifuged (2500 rpm) at 5 °C for 15 mins. The tube was
taken out, allowed to cool and pipetted 15 ml of supernatant into another centrifuge tube.
The pH was adjusted up to 7 with 10 % oxalic acid (care and patience is required if pH
drops to less than pH 7, slowly add a drop of saturated Ca (OH)2 solution until pH 7 is
reached). The final volume was made with de-ionized water up to 25 ml, capped, mixed
well and again centrifuged (2500 rpm) at 5 ᵒC for 15 min.
The C18 Sep-Pak cartridge (500 mg) was connected with 500 mg SCX
cartridge in series (C18 cartridge on top) using a column adaptor. The conditioning of the
cartridges was done by passing the methanol (10 ml) followed by deionized water
(10 ml). The 10 ml supernatant of the digested sample was loaded onto the column and
the eluent was collected into test tube. The eluent was evaporated with a stream of
nitrogen and re-dissolved the residue with 2 ml of de-ionized water (Ward and Trenerry,
1997).
Determination of vitamin C (mg 100g-1
)
The 2.5 g sample was homogenized with 3% metaphosphoric acid,
transferred to the 100 ml volumetric flask and made the final volume with 3%
metaphosphoric acid. The sample was shacked vigorously for 5 minutes and placed into
65
ultrasonic bath for 10 minutes. The solution was passed through membrane filter
0.45 μm by using filtration assembly (Lakshanasomya, 1998).
Determination of β- Carotene (mg 100g-1
)
One gram of sample was taken into round bottom brown flask (250ml) and
added with 10 ml of the ascorbic acid, 40 ml ethanol and 10 ml of KOH. The sample was
mixed thoroughly after adding each reagent. Three glass beads were added into the flask,
placed in water bath (80 °C) for 30 minutes and stir continuously (using magnetic stirrer).
The flasks were cooled at room temperature, added 50 ml of the hexane and shake
vigorously. Place the flasks untouched until two layers appeared, and then transferred the
upper layer into 250 ml brown separating funnel.
The sample was extracted again in saponification flask 2 times with 40 ml
each of extraction solvent and combined the upper layers into the separating funnel.
Shake the separating funnel and allowed the layers to be separated and discarded the
lower layer. The sample was dried by means of a rotary vacuum evaporator (<30 °C) and
flushed with nitrogen gas. The dried sample was dissolved immediately with 10 ml
methanol, filtered through a 0.45 μm membrane using solvent filtration apparatus and
collected into brown vials for HPLC analysis (Horwitz, 2000 and Thaifoods, 2002).
66
Table 5. HPLC conditions for quantification of vitamins
Thiamine Riboflavin Niacin β- Carotene Ascorbic
Acid
Column
Supelco LC-18
column
(250mm×
4.6mm ID,
5μm) (Supelco
Park,
Bellefonte,
USA)
Supelco LC-
18 column
(250mm×
4.6mm ID,
5μm)
(Supelco
Park,
Bellefonte,
USA)
Supelco
LC-18
column
(250mm×
4.6mm ID,
5μm)
(Supelco
Park,
Bellefonte,
USA)
Supelco LC-
18 column
(250mm×
4.6mm ID,
5μm)
(Supelco
Park,
Bellefonte,
USA)
Supelco
LC-18
column
(250mm×
4.6mm ID,
5μm)
(Supelco
Park,
Bellefonte,
USA)
Mobile
Phase
Ratio: Methanol
and de-ionized
water
50:50
Ratio:
Methanol
and de-
ionized water
85:15
Ratio:
Methanol
and de-
ionized
water
50:50
Ratio:
Acetonitrile:
Methanol:
Chloroform
89:9:2
Ratio: 0.3
M
potassium
dihydrogen
phosphate
in
0.35% (v/v)
ortho-
phosphoric
acid
Detector Fluorescencedet
ector
Fluorescence
detector
Ultraviolet
detector
Ultraviolet
detector
Ultraviolet
detector
Wavelengt
h 440nm 360 nm 254 nm 450 nm 248 nm
Injection
Volume
10 μl
10 μl
10 μl
20 μl
20 μl
Flow Rate 1.3 ml/min 1.3 ml/min 0.5 ml/min 1.5 ml/min 3.11
ml/min
Phytochemical analysis
The phytochemical samples were estimated by using the standard methods
of composition.
67
Alkaloids Determination (mg g-1
)
The 5 g sample was taken into a beaker (250 ml) with acetic acid (10% in
200 ml ethanol), covered and left for four hours. The sample was filtered and the filtrate
was concentrated by placing the sample in a water bath at 60 °C until it remained ¼ of its
previously taken volume. The ammonium hydroxide (conc.) was drop wise included to
the extracted material till precipitates appeared. The precipitated sample was rinsed with
a diluted ammonium hydroxide solution and passed through Whatman No. 42 (Harborne,
1993). The residue of filtrate was the alkaloids were calculated as percentage of the
dried fraction by using the formula;
Where;
W1= weight of the sample
W2= Weight of the filter paper
W3= Weight of the filter paper with precipitate
Flavonoid determination (mg g-1
)
The 10 g sample was placed in a mixture of ethanol (95%, 3 ml),
aluminium chloride (10%, 0.2 ml), potassium acetate (1 M, 0.2 ml) and distilled water
(5.6 ml) for 30 minutes at ambient temperature till the color development. The
absorbance of the sample solutions was determined at 415 nm on a UV–Vis
spectrophotometer and the concentration of flavonoids determined using a standard
curve of quercetin. The quercetin working standard solutions (1, 5, 10, 25, 50, 75 and
68
100 ppm in 80% ethanol) were prepared from the quercetin stock standard solution. A
1mL of each of the working standard solutions was mixed with ethanol (95%, 3 ml),
aluminium chloride (10%, 0.2 ml), potassium acetate (5%, 0.2 ml) and distilled water
(5.6 ml), left for 30 minutes at room temperature for full colour development and
absorbance read on a UV–Vis spectrophotometer at 415 nm. A blank was run
together with the working standard solutions with distilled water replacing the extracts
or the wine as per method reported by Humadi and Istudor (2008). The final
concentration of the sample was determined using the equation
Saponin determination (mg g-1
)
The sample of 5 g was placed in a beaker and added 200 ml of the ethanol
(20%). The sample was transferred to the water bath with the continuous magnetic stirrer
for four hours at 55 °C. The sample was passed by whatman 42 number paper and
residues were extracted again with ethanol if about 200 ml (20%). The solution was then
again placed over a water bath at 90 °C making the final volume of about 40 ml. The
solution was put into the separating funnel of 250 ml capacity and added 20 ml of diethyl
ether to it. The separating funnel was then covered and shacked vigorously for 2 minutes.
The layer of ether was discarded, whereas the aqueous layer was collected into a conical
flask. The process repeated again and the purification process was repeated and then
added with n-butanol (60 ml). The extracts of n-butanol were rinsed twice with NaCl
(5%) solution for twice. The sample remained was warmed to evaporate the solution to a
69
persistent weight and calculated for the saponin (Obadoni and Ochuko, 2001) by the
given formula;
Where;
W1= weight of the sample
W2= Weight of the empty flask
W3= Weight of the flask with evaporated sample
Determination of total phenols (mg g-1
GAE)
The sample of 10 g was taken into a beaker, included ether (50 ml) and
boiled for 5 minutes. 5 ml of the solution was then taken into a volumetric flask (50 ml)
and added 10 ml of de-ionized water, amyl alcohol (5 ml) and 2 ml ammonium
hydroxide. The solution was made up to the mark with the help of deionized water and
allowed to stand untouched for 30 minutes for the development of colored solution. The
sample was then read at wavelength of 765 nm on UV-spectrophotometer (Ebrahimzadeh
et al., 2008).
Simultaneously 1, 5, 10, 25, 50, 75 and 100 ppm gallic acid working
standards were prepared from the gallic acid standard stock solution in separate 100
mL volumetric flasks. A 1 mL aliquot of each of the working standard solutions was
treated in the same way as the sample. A calibration curve was plotted from the
absorbance of the working standards and their concentrations. The concentrations of the
sample reported as gallic acid equivalent (GAE) was calculated from the equation
(Lee, 2004).
70
Tannin determination (mg g-1
)
The sample of 10 g was taken into plastic bottle of 100 ml, then de-
ionized water (50 ml) was added and subjected to shaking for an hour on a power-driven
shaker. The sample was passed by filtration into a volumetric flask of 50 ml and
prepared the volume de-ionized water. About 5 ml of the filtrate was pipetted into a 25
ml test tube and added 3 ml of each Fe Cl3 (0.1 M), HCl (0.1 N) and potassium
ferrocyanide (0.008 M), 30 minutes was allowed for full color development. The
spectrophotometer equipped with UV spectra was used to measure the absorbance of the
sample at 760 nm within 10 minutes against a blank sample (Boham and Kocipai,
1994). The standard tannic acid solutions (1, 5, 10, 25, 50, 75 and 100 ppm) were
prepared. Concentrations of the samples were calculated from standard curve using
an equation:
Where;
A1= Absorbance of the std.
A2= Sample absorbance
C= Standard concentration
M= Mass of the sample
71
Total solids, total soluble solids, energy value, pH, nitrogen free extract and fatty
acid analyses
Total solids determination (%)
The total solids of given sample were calculated by subtracting its
moisture percentage from hundred (James, 1995).
Total soluble solids determination (ᵒBrix)
Total soluble solid (TSS) was determined according to the method of
Mazumdar and Majumder (2003). First of all machine was cleaned and calibrated to zero
with the help of distilled water. Vegetable samples were mashed into pestle and mortar
and the sample was placed on the prism of the refractometer with the help of spatula.
Next the lid of refractometer was closed and results were noted in terms of ᵒBrix. For
each sample of vegetable same technique was applied. The results were obtained in
triplicate to reduce the error.
Energy value determination (Kcal 100g-1
)
The calorific value in the form of Kcal 100g-1
of a given sample was
obtained by the formula of Asibey-Berko and Taiye (1999).
72
Determination of pH
The pH is the hydrogen ion concentration of any given sample, determined
by using a digital pH meter (AOAC, 2000). Solutions with buffer tablets of pH 4 and 10
were prepared in order to ensure accuracy of digital pH apparatus. The probe of the
apparatus was rinsed with de-ionized water, dried with tissue paper and then inserted into
the buffer solution when accurate results obtained the electrode was rinsed again with
distilled water, dried and inserted into the sample and recorded its pH concentration.
Percentage nitrogen free extracts (%)
The percentage Nitrogen free extract (NFE) was obtained by the procedure
of Owolabi et al. (2012).
Percentage total fatty acid content (%)
Total fatty acids were determined by multiplying conversion factor of 0.80
with the crude fat (%) of a given sample (Greenfield and Southgate, 2003; Akinyeye et
al., 2010, 2011).
Extraction and estimation of chlorophyll pigments (mg g-1
)
Chlorophyll estimation was carried out according to Arnon (1949). This
procedure was carried out in dim light in order to reduce photo-destruction of the
pigments. Healthy, fresh samples of the above mentioned species were collected and 1
73
gram of each was weighed and crushed to make its pulp with 20 ml acetone (80 %) in the
lab scale grinder.
The paste was transferred to the centrifuge tube and the pestle and mortar
were rinsed with acetone and added to the tube. The sample was then centrifuged with 10
ml of acetone (80% freshly prepared) at 5000 rpm for 5 minutes and the supernatant was
collected in a beaker of 50 ml. The solution was transferred to the 100 ml volumetric
flask and made the final volume with de-ionized water. The sample was then recorded at
the wavelengths of 645 and 663 nm against the acetone (80%) as a blank solution through
a spectrophotometer of UV spectra. The quantification of factor in order to get
chlorophyll content in mg/g was obtained as follows:
Where, V= final volume made = 100 ml
W= fresh weight of sample = 1 g.
The equations for the calculation of the total chlorophyll, chlorophyll a and chlorophyll b
were obtained by following the formulas given below:
Where, A663 = absorbance at 663 nm
A645 = absorbance at 645 nm
74
Statistical analyses
Data was analyzed from analysis of variance (ANOVA) using two factor
factorial along with Complete Randomised Design (CRD) to find out levels of
significance among various treatments and their interactions. The levels of significance
between means were estimated by the least significant difference (LSD) method at <
0.05 was considered statistically significant following the procedures of Steel and Torrie
(1980). Correlation analysis was performed to determine the relationship between each
quality parameter of vegetables. Principal component analysis was performed to study the
relationships between nutritional content of selected vegetables using SPSS 16.
75
CHAPTER-IV
RESULTS
The main purpose of current research work was to assess the nutritional
quality of nontraditional vegetables wildly grown in Sindh. The content of the present
study includes field survey in Mirpurkhas district of Sindh and laboratory tests for quality
characteristics of vegetables. The data generated from the present study was statistically
analyzed and the results are interpreted in the following sections.
Perception of non-traditional vegetable use by selected of respondents
Percent frequency data in Table 6 (Figure 4) shows respondents perception
about utilization of non-traditional vegetables. It has been observed from the survey that
gram leaves vegetable was the most popular non-traditional vegetable eaten frequently or
occasionally by 82% respondents only 18% respondents never tasted or do not know this
vegetable. Next popular vegetables which majority of respondent never tasted or did not
know included amaranthus and lamb's quarter. About 62% respondents never tasted or do
not know horse radish tree flowers as vegetable while 38% respondents answered they
eat frequent or occasionally.
76
Table 6. Perception of non-traditional leafy vegetable use by selected respondents
(% frequency)
Vegetable Name
Do not
know
Never
tasted
Eat
occasionally
Eat
frequently Total
1 2 3 4
Lamb's quarter 38 21 16 25 100
Amaranthus 34 19 29 18 100
Gram leaves 10 08 34 48 100
Horse radish tree
flowers 27 35 30 08 100
Figure 4. Perception of nontraditional vegetable use
Proximate composition of vegetables
Determination of percent moisture in selected vegetables
Statistical ANOVA for processing methods, type of vegetables and their
interaction showed significant differences for moisture content (Appendix V). Spinach
had higher moisture content (54.46%), which was followed by 51.29% moisture content
in horse radish tree flowers. The least moisture content (48.36%) was detected in samples
77
of amaranthus (Table 7). Moisture content as influenced by processing methods revealed
significant differences. The maximum (86.51%) moisture content was observed in boiled
vegetables, followed by 83.61% moisture content in fresh vegetables (control). Whereas,
minimum moisture content (6.277%) was noted in thermally dehydrated vegetables
(Table 7). Interactive effect of processing methods and vegetable types showed
significant effect on moisture content. The highest moisture content (92.66%) was found
in spinach under boiled method followed by 88.76% moisture content in the same
vegetable at fresh (control), whereas least i.e. 4.93% was observed in horse radish tree
flowers at thermal dehydration method (Table 7, Figure 5).
Table 7. Moisture content (%) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 81.96
ef
±0.33
83.05ef
±0.31
65.50j
±3.3
5.407m
±1.13
5.883m
±0.11 48.36
D
Lambs quarter 84.08
de
±0.72
85.46cd
±0.64
71.42h
±0.25
6.417lm
±0.31
7.180lm
±0.45 50.91
B
Gram leaves 82.28
ef
±0.10
84.13de
±0.89
68.76i
±0.91
6.00m
±0.36
6.22m
±0.63 49.47
C
Horse radish tree
flowers
80.98f
±0.24
87.26bc
±0.34
77.46g
±0.42
4.933m
±0.79
5.840m
±0.22 51.29
B
Spinach 88.76
b
±0.41
92.66a
±0.08
72.46h
±1.13
8.627kl
±0.18
9.833k
±0.12 54.46
A
Mean 83.61B 86.51
A 71.12
C 6.277
D 6.991
D
`Means within columns and rows followed by same letters are not significantly different
at 5% probability level
78
Figure 5. Graphical representation of the moisture content (%) of selected
vegetables
Determination of percent ash in selected vegetables
ANOVA for ash content is shown in Appendix VI. Analysis indicated
significant differences for processing methods, vegetables and interaction of processing ×
vegetables. Among the vegetables, horse radish tree flowers had maximum (7.23%) ash
content followed by amaranthus (5.489%). The minimum (3.965%) ash content was
noted in spinach (Table 8). Processing methods had significant effect on ash content and
the highest value of ash content (11.06%) was recorded under thermall dehydration
method followed by 9.915% ash content in shade dried vegetables. While, lowest value
(0.996%) of ash content was observed in boiled samples of vegetables (Table 8). Ash
content under the interactive effect of vegetable type x processing method showed
maximum ash content (16.15%) in horse radish tree flowers under thermall dehydration
followed by 14.82% ash content in the same vegetable under shade dry method.
However, lower (0.507%) ash content was noted in spinach at boiling (Table 8, Figure 6).
79
Table 8. Ash content (%) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 2.353
j
±0.19
1.227l
±0.05
3.813h
±0.18
10.56c
±0.25
9.493d
±0.94 5.489
B
Lambs quarter 2.013
jk
±0.06
1.187l
±0.03
2.127jk
±0.06
9.507d
±0.05
8.287e
±0.07 4.624
D
Gram leaves 2.233
jk
±0.12
1.213l
±0.06
3.227i
±0.07
10.43c
±0.27
9.220d
±0.06 5.264
C
Horse radish tree
flowers
4.873g
±0.11
0.847lm
±0.08
1.927k
±0.07
16.15a
±0.07
14.82b
±0.08 7.23
A
Spinach 0.887
lm
±0.05
0.507m
±0.09
2.00jk
±0.09
8.680e
±0.08
7.753f
±0.06 3.965
E
Mean 2.472C 0.996
D 2.619
C 11.06
A 9.915
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 6. Graphical representation of the ash content (%) of selected vegetables
80
Determination of percent protein in selected vegetables
ANOVA for protein content is revealed in Appendix VII. The results for
protein content represented significant differences (P≤0.01) among types of vegetable,
types of processing and their interaction. Protein content was highest (5.90%) in gram
leaves, while the horse radish tree flowers ranked second with 4.62%. Whereas, the
minimum protein content 2.37% was recorded from samples of spinach (Table 9).
Processing methods displayed significant differences for protein content. The maximum
protein content (5.412%) was noted in thermally dehydrated vegetables followed by
4.890% in shade dried. Whereas, the lowest protein content (2.883%) was detected from
boiled vegetable samples (Table 9). Interactive effect of vegetable type and processing
type showed significantly greater protein content (7.56%) in gram leaves under thermal
dehydration method. However, minimum protein of 1.04% was found in spinach under
boiling method (Table 9, Figure 7).
81
Table 9. Protein content (%) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 3.273
j
±0.06
2.293k
±0.05
3.073j
±0.70
5.183def
±0.06
4.833efg
±0.03 3.73
D
Lambs quarter 4.306
hi
±0.86
3.170j
±0.05
4.043i
±0.03
4.303de
±0.03
4.76fgh
±0.03 4.13
C
Gram leaves 5.916
c
±0.05
4.570gh
±0.08
4.916efg
±0.03
7.560a
±0.07
6.55b
±0.03 5.90
A
Horse radish tree
flowers
4.746fgh
±0.005
3.342j
±0.105
4.250hi
±0.008
5.530cd
±0.05
5.226def
±0.005 4.62
B
Spinach 2.170
k
±0.51
1.040l
±0.019
2.086k
±0.42
3.483j
±0.31
3.08j
±0.37 2.37
E
Mean 4.082C 2.883
E 3.674
D 5.412
A 4.890
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 7. Graphical representation of the protein content (%) of selected vegetables
82
Determination of percent fat in selected vegetables
Statistical ANOVA for vegetables, processing methods and interaction of
vegetables and processing methods revealed significant differences (P≤0.01) for fat
content (Appendix VIII). Fat content in various types of vegetables revealed significant
differences. The higher fat content of 2.73 and 2.62% was observed in horse radish tree
flowers and spinach, respectively. Whereas, the lowest fat content (1.62%) was found in
lambs quarter (Table 10). Fat content under the effect of processing methods represented
significant differences. Fat content had higher value of 3.30% in curry or cooked
vegetables which was followed by 2.37% detected in thermally dehydrated vegetables.
However, minimum fat content (1.29%) was found in boiled vegetables (Table 10). The
results for fat content under the interactive effect of vegetables and processing methods
indicated maximum value of 3.85% in horse radish tree flowers under cooking method
while minimum fat content i.e. 0.85% and 0.75% was found in gram leaves and lambs
quarter, respectively at boiling method (Table 10, Figure 8).
Table 10. Fat (%) of different types of vegetables under the effect of postharvest
processing methods
83
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 2.15
defghi
±0.18
1.10kl
±0.22
3.40ab
±0.26
2.55cde
±0.42
2.31cdefgh
±0.39 2.30
B
Lambs quarter 1.25
jkl
±0.27
0.75l
±0.18
2.85bc
±0.27
1.70hijk
±0.21
1.57ijk
±0.45 1.62
C
Gram leaves 1.60
ijk
±0.31
0.85l
±0.25
2.75cd
±0.82
2.01efghi
±0.21
1.99efghi
±0.47 1.84
C
Horse radish tree
flowers
2.40cdefg
±0.13
1.90fghi
±0.26
3.85a
±0.27
2.85bc
±0.45
2.65cd
±0.68 2.73
A
Spinach 2.35
cdefg
±0.35
1.850ghij
±0.42
3.65a
±0.52
2.75cd
±0.21
2.50cdef
±0.25 2.62
A
Mean 1.95C 1.29
D 3.30
A 2.37
B 2.203
BC
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 8. Graphical representation of the fat content (%) of selected vegetables
84
Determination of percent fiber in selected vegetables
Fiber content was significantly (P≤0.01) affected by processing methods.
However, type of vegetables and interaction of vegetables × processing methods showed
non-significant effect on fiber content (Appendix IX). The results for fiber content in
different vegetables revealed significant differences and ranged from 5.163% to 6.67%
(Table 11). Processing methods had significant effect on fiber content. The thermally
dried vegetables had higher fiber content i.e. 10.83%, while the lowest (1.817%) fiber
content was noted in boiled vegetables (Table 11). The results for fiber content under the
interactive effect of vegetables and processing methods showed the highest value
(13.35%) in thermally dried sample of horse radish tree flowers whereas the lowest value
was recorded in boiled sample of spinach (Table 11, Figure 9).
85
Table 11. Fiber content (%) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 2.60
efgh
±0.45
2.350ghi
±1.34
4.250d
±0.15
10.383bc
±0.37
10.10c
±2.52 5.936
B
Lambs quarter 2.167
ghi
±0.10
1.550hi
±0.49
3.950de
±0.10
10.15bc
±0.44
9.583c
±0.37 5.48
BC
Gram leaves 2.550
fgh
±0.18
1.700hi
±0.104
3.13d
±0.18
10.50bc
±0.18
9.80c
±0.57 5.736
BC
Horse radish tree
flowers
2.70efgh
±0.21
2.450fgh
±0.95
3.367defg
±0.15
13.35a
±0.32
11.48b
±0.60 6.67
A
Spinach 2.083
ghi
±0.27
1.033i
±0.13
3.750def
±0.02
9.750c
±0.22
9.200c
±0.25 5.163
C
Mean 2.420D 1.817
D 3.890
C 10.83
A 10.03
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 9. Graphical representation of the fiber content (%) of selected vegetables
86
Determination of percent carbohydrate in selected vegetables
Statistical analysis showed a significant effect of type of vegetables, processing
methods and their interaction on carbohydrate content as shown in Appendix X. The
higher (34.18%) carbohydrate content was noted in amaranthus whereas the minimum
carbohydrate of 26.96% was recorded in horse radish tree flowers (Table 12).
Carbohydrate content was influenced by processing methods and displayed significantly
highest carbohydrate content of 65.96 and 64.02% in shade dried and thermally
dehydrated vegetables, respectively followed by 15.42% carbohydrate content in curry.
However, least carbohydrate content was obtained in fresh (5.463%) and boiled (6.503%)
vegetables (Table 12). Interactive effect of vegetable types × processing methods
produced significantly higher carbohydrate (698.62%) in lambs quarter at shade drying.
However, lesser carbohydrate (2.91%) was noted in spinach at boiling (Table 12, Figure
10).
87
Table 12. Carbohydrate (%) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 7.660
efg
±0.66
9.980e
±0.74
20.08d
±0.56
65.80a
±9.62
67.38a
±2.07 34.18
A
Lambs quarter 6.183
efg
±0.61
7.887efg
±0.50
15.61d
±0.28
66.92a
±0.19
68.62a
±0.63 33.04
AB
Gram leaves 5.423
efg
±0.35
7.537efg
±0.30
16.21d
±0.78
63.50ab
±0.42
66.22a
±0.42 31.77
B
Horse radish tree
flowers
4.300fg
±0.17
4.200fg
±0.56
9.150ef
±1.02
57.19c
±0.19
59.96bc
±0.34 26.96
C
Spinach 3.747
g
±0.49
2.910g
±0.27
16.05d
±0.98
66.71a
±0.33
67.63a
±0.51 31.41
B
Mean 5.463C 6.503
C 15.42
B 64.02
A 65.96
A
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 10. Graphical representation of the carbohydrate content (%) of selected
vegetables
88
Correlation matrix (r) of proximate composition of different vegetables
The data on correlation study of proximate composition of different
vegetables under the influence of various processing treatments are presented in Table
13. Moisture content exhibited a significant (P≤0.01) negative association with ash (r= -
0.922), fiber (r = -0.968), carbohydrate (r = -0.990) and protein (r = -0.557) of different
vegetables whilst a non-significant negative correlation was observed with fat (r = -
0.152). Likewise, ash showed a significant positive relationship with fiber (r = 0.949),
carbohydrate (r = 0.875) and protein (r = 0.600) while a non-significant positive
correspondence was observed with fat (r = 0.185). There was observed a non-significant
positive correlation for fiber with respect to fat (r = 0.211) and significant (P≤0.01)
positive correlation was noticed with protein (r = 0.558) and carbohydrate (r = 0.939). Fat
showed non significant negative correlation with protein (r = -0.055) whereas a non-
significant positive association was found in carbohydrate (r = 0.118). Carbohydrate
showed a significant (P≤0.05) positive correlation with protein (r = 0.503).
Table 13. Correlation matrix (r) of proximate composition of different vegetables
under the influence of processing treatments
Moisture Ash Fiber Fat Carbohydrate Protein
Moisture 1
Ash -0.922** 1
Fiber -0.968** 0.949** 1
Fat -0.152 0.185 0.211 1
Carbohydrate -0.990** 0.875** 0.939** 0.118 1
Protein -0.557** 0.600** 0.558** -0.055 0.503* 1
** = P<0.01; * = P<0.05, levels of significance.
89
Organic acids of different vegetables
Determination of percent acetic acid in selected vegetables
Type of vegetables, processing methods and their interaction showed a
significant effect on acetic acid content (Appendix XI). The acetic acid content in
amaranthus, lambs quarter, gram leaves, horse radish tree flowers and spinach was in
order of 0.08, 0.048, 0.058, 0.067 and 0.054%, respectively (Table 14). Acetic acid as
influenced by processing methods revealed significant differences and showed higher
value of 0.118% in thermally dehydrated samples of vegetables whereas the lowest value
of 0.017% acetic acid was found in boiled vegetables (Table 14). Interactive effect of
processing methods × vegetables represented highest acetic acid i.e. 0.143% in
amaranthus at thermal dehydration method (Table 14, Figure 11).
Table 14. Acetic acid (%) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 0.05
f
±0.003
0.03gh
±0.003
0.04fg
±0.003
0.143a
±0.009
0.136a
±0.003 0.08
A
Lambs quarter 0.016
hij
±0.006
0.01j
±0.003
0.02hij
±0.007
0.103de
±0.006
0.09e
±0.029 0.048
D
Gram leaves 0.023
hij
±0.002
0.013ij
±0.001
0.026ghi
±0.003
0.120bc
±0.002
0.11cd
±0.001 0.058
C
Horse radish tree
flowers
0.040fg
±0.003
0.02hij
±0.006
0.030gh
±0.003
0.113cd
±0.021
0.133ab
±0.015 0.067
B
Spinach 0.020
hij
±0.003
0.013ij
±0.003
0.020hij
±0.002
0.113cd
±0.021
0.103de
±0.021 0.054
CD
Mean 0.030B 0.017
D 0.027
B 0.118
A 0.114
A
Means within columns and rows followed by same letters are not significantly different at
5% probability level
90
Figure 11. Graphical representation of the acetic acid (%) of selected vegetables
Determination of percent citric acid in selected vegetables
ANOVA results for citric acid showed significant differences (P≤0.01)
among vegetable types, processing methods and interaction of vegetables × processing
(Appendix XII). Citric acid was higher (0.117%) in gram leaves as compared to horse
radish tree flowers (0.087%), amaranthus (0.071%), lambs quarter (0.066%) and spinach
(0.056%) and as shown in Table 15. The samples from thermally dehydrated vegetables
had highest citric acid of 0.182% whereas the lowest value of 0.022% citric acid was
found from boiled vegetables (Table 15). Citric acid under the interactive effect of
processing methods and vegetables showed highest value i.e. 0.26% in gram leaves under
thermal dehydration method (Table 15, Figure 12).
91
Table 15. Citric acid (%) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 0.026
jkl
±0.003
0.016kl
±0.004
0.026jkl
±0.003
0.170cd
±0.01
0.116f
±0.003 0.071
C
Lambs quarter 0.023
jkl
±0.007
0.013l
±0.003
0.023jkl
±0.008
0.153de
±0.007
0.116f
±0.034 0.066
B
Gram leaves 0.053
h
±0.002
0.036hij
±0.002
0.040hij
±0.003
0.260a
±0.003
0.196b
±0.002 0.117
A
Horse radish tree
flowers
0.046hi
±0.003
0.030ijkl
±0.007
0.033ijk
±0.004
0.183bc
±0.024
0.143e
±0.018 0.087
B
Spinach 0.023
jkl
±0.003
0.013l
±0.003
0.023jkl
±0.002
0.146e
±0.025
0.073g
±0.025 0.056
D
Mean 0.034C 0.022
D 0.029
CD 0.182
A 0.129
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 12. Graphical representation of the citric acid (%) of selected vegetables
92
Determination of percent oxalic acid in selected vegetables
Statistical analysis of variance (ANOVA) for vegetable types, processing
types and their interaction showed significant differences for oxalic acid (Appendix XIII).
The maximum oxalic acid (0.058%) was noted in samples of spinach whereas the rest of
the vegetables had lower values of oxalic acid i.e. from 0.029 to 0.043% (Table 16).
Among the processing methods, the oxalic acid was maximum i.e. 0.076% in thermally
dehydrated vegetables while the minimum (0.014%) oxalic acid was found from samples
of boiled vegetables (Table 16). Oxalic acid under the interactive effect of processing
methods and vegetables indicated significantly highest value of 0.113% in spinach at
thermal dehydration method (Table 16, Figure 13).
Table 16. Oxalic acid (%) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean
Fresh (control) Boiled Curry Thermally
dehydrated
Shade
dried
Amaranthus 0.016
fghi
±0.002
0.010hi
±0.002
0.020fgh
±0.002
0.06d
±0.006
0.053d
±0.002 0.032
C
Lambs quarter 0.013
ghi
±0.004
0.006i
±0.002
0.013ghi
±0.005
0.053d
±0.004
0.050d
±0.022 0.029
D
Gram leaves 0.026
e
±0.001
0.016fghi
±0.001
0.020fgh
±0.002
0.073c
±0.002
0.056d
±0.001 0.038
B
Horse radish tree
flowers
0.033e
±0.002
0.016fghi
±0.002
0.023efg
±0.002
0.083c
±0.015
0.060d
±0.011 0.043
B
Spinach 0.034
e
±0.002
0.020fgh
±0.002
0.024efg
±0.001
0.113a
±0.016
0.100b
±0.016 0.058
A
Mean 0.024C 0.014
D 0.020
CD 0.076
A 0.064
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
93
Figure 13. Graphical representation of the oxalic acid (%) of selected vegetables
Determination of percent tartaric acid in selected vegetables
Vegetable types, processing methods and their interaction had a significant
effect (P≤0.01) on tartaric acid content (Appendix XIV). Tartaric acid in amaranthus,
lambs quarter, gram leaves, horse radish tree flowers and spinach was in order of 0.076,
0.073, 0.128, 0.049 and 0.011%, respectively (Table 17). Tartaric acid was highest
(0.206%) in thermally dehydrated vegetables. However, the lowest (0.024%) tartaric acid
was found in boiled vegetables (Table 17). Interactive effect of processing methods ×
vegetables showed significantly maximum tartaric acid of 0.273% in gram leaves at
thermal dehydration process (Table 17, Figure 14).
94
Table 17. Tartaric acid (%) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh (control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 0.027
ijk
±0.004
0.020jk
±0.004
0.023jk
±0.003
0.186d
±0.011
0.126ef
±0.003 0.076
C
Lambs quarter 0.026
ijk
±0.008
0.016jk
±0.003
0.023jk
±0.008
0.183d
±0.007
0.120f
±0.037 0.073
C
Gram leaves 0.060
g
±0.003
0.046ghi
±0.002
0.050gh
±0.003
0.273a
±0.003
0.240b
±0.002 0.128
A
Horse radish tree
flowers
0.016jk
±0.003
0.008k
±0.007
0.013k
±0.004
0.146e
±0.026
0.063g
±0.019 0.049
D
Spinach 0.050
gh
±0.004
0.030hijk
±0.004
0.036hij
±0.002
0.240b
±0.027
0.183d
±0.027 0.011
B
Mean 0.035C 0.024
C 0.029
C 0.206
A 0.141
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 14. Graphical representation of the tartaric acid (%) of selected vegetables
95
Correlation matrix (r) of organic acids of different vegetables
Results on correlation analysis of organic acids of selected vegetables
under the influence of processing treatments are given in Table 18. The relationship
showed a significant (P<0.01) positive correlation for acetic acid with citric acid (r =
0.865), oxalic acid (r = 0.792) and tartaric acid (r = 0.808). The citric acid was found to
be significantly (P<0.01) positively correlated with oxalic acid (r = 0.738) and tartaric
acid (r = 0.885). A significant and positive correlation was also observed between oxalic
acid and tartaric acid (r = 0.839).
Table 18. Correlation matrix (r) of organic acids of different vegetables under the
influence of processing treatments
Acetic acid Citric acid Oxalic acid Tartaric acid
Acetic acid 1
Citric acid 0.865** 1
Oxalic acid 0.792** 0.738** 1
Tartaric acid 0.808** 0.885** 0.839** 1
** = P<0.01; * = P<0.05, levels of significance.
Mineral content of different vegetables
Determination of copper content (mg 100g-1
) in selected vegetables
Copper content under the effect of vegetable types, processing methods
and their interaction showed significant differences (P≤0.01) as indicated in Appendix
XV. Copper content in different vegetables displayed significantly maximum copper
content (1.95 mg 100g-1
) in gram leaves followed by 1.89 mg 100g-1
copper in lambs
quarter. The minimum copper of 6.07 mg 100g-1
and 1.22 mg 100g-1
was noticed in
spinach and horse radish tree flowers (Table 19). Among the processing methods, highest
96
copper content (2.19 mg 100g-1
) was observed in thermally dehydrated vegetables
followed by shade dried (1.88 mg 100g-1
). However, lowest (1.01 mg 100g-1
) copper
content was found in boiled vegetables (Table 19). Interactive effect of processing
methods × vegetables indicated highest copper content of 2.99 mg 100g-1
in gram leaves
at dehydration process whereas the lowest copper content (1.01 mg 100g-1
) was detected
from spinach under boiling (Table 19, Figure 15).
Table 19. Copper (mg 100g-1
) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh (control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 1.143
ghi
±0.002
0.99ijk
±0.003
1.090hij
±0.001
3.026a
±0.03
1.940cd
±0.04 1.63
B
Lambs quarter 1.860
cd
±0.02
1.660e
±0.02
1.790de
±0.04
2.150b
±0.02
1.990bc
±0.02 1.89
A
Gram leaves 1.35
f
±0.02
1.21fgh
±0.04
1.30fg
±0.02
2.990a
±0.03
2.900a
±0.04 1.95
A
Horse radish tree
flowers
0.950jkl
±0.03
0.803l
±0.04
0.890kl
±0.002
1.820cde
±0.002
1.660e
±0.004 1.22
C
Spinach 0.560
m
±0.002
0.390m
±0.01
0.480m
±0.004
1.010ijk
±0.002
0.910jkl
±0.01 0.67
D
Mean 1.172C 1.01
D 1.11
C 2.19
A 1.88
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
97
Figure 15. Graphical representation of the copper content (mg 100g
-1) of selected
vegetables
Determination of iron content (mg 100g-1
) in selected vegetables
Analysis of variance for iron content showed significant differences
(P≤0.01) under the effect of vegetable types, processing methods and their interaction
(Appendix XVI). Vegetable type displayed significantly higher iron content (4.394 mg
100g-1
) in gram leaves followed by 2.906 mg 100g-1
in amaranthus, while the lowest iron
content (1.042 mg 100g-1
) was noted in horse radish tree flowers (Table 20). Processing
methods showed significantly maximum iron content of 2.87 mg 100g-1
in thermally
dehydrated samples of vegetables, while shade dried method ranked second with 2.748
mg 100g-1
, whereas lowest iron content (1.932 mg 100g-1
) observed in boiled vegetables
(Table 20). Interactive effect of processing methods × vegetables showed greater iron
content i.e. 4.810 mg 100g-1
in gram leaves at thermal dehydration process. However,
98
lower iron content of 0.77 mg 100g-1
was detected in spinach after boiling process (Table
20, Figure 16).
Table 20. Iron (mg 100g-1
) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 2.990
fg
±0.04
2.580h
±0.04
2.760gh
±0.004
3.190ef
±0.02
3.010fg
±0.02 2.906
B
Lambs quarter 2.120
i
±0.02
1.800j
±0.02
1.990ij
±0.002
3.460d
±0.02
3.360de
±0.04 2.546
C
Gram leaves 4.520
ab
±0.05
3.830c
±0.02
4.050c
±0.04
4.810a
±0.02
4.760ab
±0.05 4.394
A
Horse radish tree
flowers
1.040mn
±0.02
0.680p
±2.00
0.870nop
±0.02
1.390kl
±0.03
1.230lm
±0.04 1.042
E
Spinach 1.210
l,
±0.002
0.770op
±0.005
0.980mno
±0.02
1.500k
±0.04
1.380kl
±0.04 1.168
D
Mean 2.376C 1.932
E 2.130
D 2.870
A 2.748
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 16. Graphical representation of the iron content (mg 100g
-1) of selected
vegetables
99
Determination of zinc content (mg 100g-1
) in selected vegetables
The zinc content indicated significant variations (P≤0.01) under the
influence of vegetable types, processing methods and their interaction (Appendix XVII).
The results for zinc content in different vegetables represented maximum value of 4.918
mg 100g-1
in amaranthus, while the lambs quarter ranked second which was observed as
4.45 mg 100g-1
. The least zinc content (2.94 mg 100g-1
) was found in horse radish tree
flowers (Table 21). Zinc content under the effect of processing methods showed
maximum value of 5.96 mg 100g-1
in thermally dehydrated vegetables followed by shade
dried method (5.48 mg 100g-1
) as compared to minimum (2.02 mg 100g-1
) zinc content in
boiled vegetables (Table 21). Interactive effect of processing methods and vegetables
exhibited significantly lowest zinc content of 1.04 mg 100g-1
in horse radish tree flowers
after boiling process whereas the highest zinc content i.e. 7.240 mg 100g-1
was noted
from amaranthus after thermal dehydration process (Table 21, Figure 17).
100
Table 21. Zinc (mg 100g-1
) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 4.66
gh
±0.02
2.68lm
±0.02
3.16j
±0.01
7.240a
±0.02
6.85b
±0.02 4.918
A
Lambs quarter 3.46
i
±0.03
2.86kl
±0.02
2.96jk
±0.002
6.86b
±0.02
6.11c
±0.04 4.45
B
Gram leaves 2.86
kl
±0.04
2.15o
±0.02
2.36no
±0.04
5.58d
±0.02
5.01ef
±0.06 3.59
C
Horse radish tree
flowers
2.35no
±0.03
1.04r
±0.02
1.75p
±0.02
5.02ef
±0.02
4.56h
±0.02 2.94
E
Spinach 2.55
mn
±0.03
1.37q
±0.04
1.85p
±0.04
5.13e
±0.004
4.88fg
±0.005 3.15
D
Mean 3.17C 2.02
E 2.41
D 5.96
A 5.48
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 17. Graphical representation of the zinc content (mg 100g
-1) of selected
vegetables
101
Determination of manganese content (mg 100g-1
) in selected vegetables
Analysis of variance for manganese content indicated significant
differences (P≤0.01) for vegetable types, processing methods and their interaction
(Appendix XVIII). Manganese content showed highest value of 1.608 mg 100g-1
in gram
leaves followed by 1.177 mg 100g-1
in amaranthus. The minimum manganese of 0.788
mg 100g-1
was recorded in spinach (Table 22). Among processing methods, manganese
content the maximum manganese content (1.336 mg 100g-1
) was detected in thermally
dehydrated vegetables followed by 1.187 mg 100g-1
in shade dried vegetables, whereas
the minimum manganese of 0.868 mg 100g-1
found in boiled vegetables (Table 22).
Manganese content under the effect of processing methods × vegetables exhibited
maximum value of 1.950 mg 100g-1
in gram leaves at thermal dehydration method,
whereas least manganese (0.490 mg 100g-1
) was determined in gram leaves at boiling
process (Table 22, Figure 18).
102
Table 22. Manganese (mg 100g-1
) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 1.190
def
±0.02
1.036ghi
±0.04
1.073fgh
±0.02
1.310d
±0.02
1.276d
±0.02 1.177
B
Lambs quarter 0.896
jkl
±0.02
0.836klm
±0.02
0.910ijkl
±0.002
1.110efg
±0.004
1.010ghij
±0.002 0.952
C
Gram leaves 1.670
b
±0.03
1.230de
±0.02
1.510c
±0.02
1.950a
±0.04
1.680bc
±0.04 1.608
A
Horse radish tree
flowers
0.960hijk
±0.02
0.750m
±0.04
0.810lm
±0.03
1.240de
±0.04
1.080fgh
±0.04 0.968
C
Spinach 0.783
lm
±0.02
0.490n
±0.04
0.710m
±0.003
1.070fgh
±0.004
0.890jkl
±0.004 0.788
D
Mean 1.100C 0.868
E 1.002
D 1.336
A 1.187
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 18. Graphical representation of the manganese content (mg 100g-1
) of
selected vegetables
103
Determination of calcium content (mg 100g-1
) in selected vegetables
Calcium content showed significant differences (P≤0.01) under the effect
of vegetable types, processing methods and their interaction (Appendix XIX). Among the
vegetables, calcium content was higher (424 mg 100g-1
) in horse radish tree flowers,
while the lambs quarter ranked second with 391.8 mg 100g-1
. Whereas, lower calcium
content of 206.3 mg 100g-1
was found in gram leaves (Table 23). Processing methods had
significant effect on calcium content and showed maximum calcium content (437.5 mg
100g-1
) in thermally dehydrated vegetables followed by shade dried (401.7 mg 100g-1
) as
compared to 215.5 mg 100g-1
calcium content from boiled vegetables (Table 23).
Interaction of processing methods and vegetables represented highest calcium content
(568.8 mg 100g-1
) in lambs quarter after dehydration process. However, the lower
calcium content (120.8 mg 100g-1
) was found in gram leaves after boiling (Table 23,
Figure 19).
104
Table 23. Calcium (mg 100g-1
) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 275.8
j
±0.002
247.5m
±0.02
263.2l
±0.04
501.1c
±0.03
476.8d
±0.02 352.8
C
Lambs quarter 309.6
h
±0.43
268.7k
±0.06
288.3i
±0.04
568.8a
±0.03
523.7b
±0.05 391.8
B
Gram leaves 181.4
o
±0.26
120.8s
±0.02
156.1q
±0.04
308.4h
±0.02
265.1l
±0.02 206.3
E
Horse radish tree
flowers
448.1f
±0.03
309.4h
±0.02
412.6g
±0.26
497.6c
±0.04
453.7e
±0.02 424.2
A
Spinach 199.5
n
±0.26
131.2r
±0.26
167.4p
±0.02
311.8h
±0.04
289.3i
±0.06 219.8
D
Mean 282.8C 215.5
E 257.5
D 437.5
A 401.7
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 19. Graphical representation of the calcium content (mg 100g
-1) of selected
vegetables
105
Determination of magnesium content (mg 100g-1
) in selected vegetables
Analysis of variance showed that magnesium content was significantly
affected by vegetable types, processing methods and their interaction (Appendix XX).
The maximum magnesium content (78.66 mg 100g-1
) was noted in lambs quarter
followed by amaranthus (73.46 mg 100g-1
), while the minimum value (33.42 mg 100g-1
)
of magnesium was observed in spinach (Table 24). Magnesium content as influenced by
processing methods revealed significantly highest value of 79.83 mg 100g-1
in thermally
dehydrated vegetables while the shade dried vegetables ranked second with 73.63 mg
100g-1
, whereas the minimum magnesium content (31.34 mg 100g-1
) noted in boiled
vegetables (Table 24). The greater magnesium content (108.4 mg 100g-1
) under the
interactive effect of processing methods × vegetables was observed from lambs quarter
after thermal dehydration treatment. The minimum magnesium content (11.34 mg 100g-1
)
was detected in spinach after boiling (Table 24, Figure 20).
106
Table 24. Magnesium (mg 100g-1
) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 72.60
g
±0.004
41.85s
±0.02
57.12l
±0.04
101.3b
±0.02
94.43d
±0.02 73.46
B
Lambs quarter 79.03
e
±0.02
46.13q
±0.02
62.26j
±0.04
108.4a
±2.00
97.43c
±1.00 78.66
A
Gram leaves 68.23
i
±0.43
38.23t
±2.00
52.53n
±0.04
77.45f
±2.00
71.53h
±1.00 61.59
C
Horse radish tree
flowers
44.38r
±1.00
19.18x
±0.07
32.75v
±0.02
61.81k
±0.36
56.50m
±1.00 42.92
D
Spinach 35.95
u
±0.06
11.34y
±0.04
21.17w
±0.06
50.16o
±1.00
48.50p
±0.28 33.42
E
Mean 60.04C 31.34
E 45.16
D 79.83
A 73.67
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 20. Graphical representation of the magnesium content (mg 100g
-1) of
selected vegetables
107
Determination of sodium content (mg 100g-1
) in selected vegetables
Analysis of variance indicated that vegetable types, processing methods
and their interaction had a significant effect on sodium content (Appendix XXI). The
results for sodium content revealed maximum (806.1 mg 100g-1
) value in lambs quarter
followed by 771.5 mg 100g-1
sodium content in spinach, whereas the lowest (650.2 mg
100g-1
) sodium content was noted in horse radish tree flowers (Table 25). Thermally
dehydrated vegetables had higher sodium content i.e. 1137.1 mg 100g-1
followed by
1067.9 mg 100g-1
sodium content in shade dried vegetables. The minimum sodium
content (470.5 mg 100g-1
) was found in boiled vegetables (Table 25). Interaction of
processing methods × vegetables resulted highest sodium content i.e. 1211.5 mg 100g-1
from lambs quarter at thermal dehydration treatment, while minimum sodium content
(391.3 mg 100g-1
) was observed in horse radish tree flowers after boiling process (Table
25, Figure 21).
108
Table 25. Sodium (mg 100g-1
) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 491.60
q
±0.43
479.60t
±0.06
554.4m
±0.04
1114.5e
±0.03
1043.5h
±0.05 736.7
D
Lambs quarter 511.40
n
±0.43
501.1o
±0.06
654.6k
±0.04
1211.5a
±0.03
1151.5d
±0.05 806.1
A
Gram leaves 499.6
p
±0.43
489.6s
±0.006
584.4l
±0.02
1153.5c
±0.03
1065.7g
±0.05 758.5
C
Horse radish tree
flowers
401.6v
±0.43
391.3w
±0.06
454.6u
±0.04
1008.5i
±0.036
995.4j
±0.05 650.2
E
Spinach 501.6
o
±0.43
490.6r
±0.06
584.6l
±0.04
1197.5b
±0.03
1083.5f
±0.05 771.5
B
Mean 481.2D 470.5
E 566.5
C 1137.1
A 1067.9
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 21. Graphical representation of the sodium content (mg 100g
-1) of selected
vegetables
109
Determination of potassium content (mg 100g-1
) in selected vegetables
Statistical ANOVA for vegetable types, processing methods and their
interaction revealed significant differences (P≤0.01) for K (Appendix XXII). Lambs
quarter had the higher potassium content (924.10 mg 100g-1
) followed by 904.1 mg 100g-
1 in lambs quarter. However, the minimum (845.2 mg 100g
-1) potassium content observed
in horse radish tree flowers (Table 26). Potassium content was significantly highest
(1059.6 mg 100g-1
) in thermally dehydrated samples of vegetables. However, the lowest
potassium content (758.5 mg 100g-1
) was found in boiled vegetables (Table 26).
Interactive effect of processing methods × vegetables showed highest potassium content
of 1081.40 mg 100g-1
in lambs quarter after thermal dehydration process. The lowest
potassium content (734.4 mg 100g-1
) was noted from horse radish tree flowers after
boiling treatment (Table 26, Figure 22).
110
Table 26. Potassium (mg 100g-1
) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 779.8
q
±0.04
744.3w
±0.03
768.3r
±0.03
1066.5c
±0.02
988.5h
±0.03 869.4
C
Lambs quarter 828.5
k
±0.02
795.0n
±0.01
817.5l
±0.02
1081.4a
±0.02
998.4f
±0.03 904.1
A
Gram leaves 764.7
s
±0.02
738.7x
±0.03
753.5u
±0.26
1040.3d
±0.02
967.3i
±0.04 852.9
D
Horse radish tree
flowers
762.4t
±0.02
734.4y
±0.02
751.5v
±0.02
1035.4e
±0.02
942.4j
±0.04 845.2
E
Spinach 796.1
m
±0.05
780.1p
±0.04
785.6o
±1.00
1074.5b
±0.03
992.5g
±0.26 885.7
B
Mean 786.3C 758.5
E 775.3
C 1059.6
A 977.8
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 22. Graphical representation of the potassium content (mg 100g
-1) of selected
vegetables
111
Correlation matrix (r) of mineral content of different vegetables
The results of correlation analysis of mineral content of different
vegetables under the effect of postharvest processing are shown in Table 27. The
relationship showed that Cu, Zn, Ca, Mg, Na and K were significantly (P≤0.01) and
positively correlated with each other. The relationship of Ca with Fe and Mn showed
nonsignificant relationship with each other. Fe and Ca showed negative whereas Mn and
Ca showed positive relation with each other.
Table 27. Correlation matrix (r) of mineral content of different vegetables under the
influence of processing treatments
Cu Fe Zn Mn Ca Mg Na K
Cu 1
Fe 0.647**
1
Zn 0.730**
0.432**
1
Mn 0.666**
0.847**
0.455**
1
Ca 0.481**
-0.059
0.681**
0.055
1
Mg 0.797**
0.626**
0.835**
0.540**
0.628**
1
Na 0.642**
0.313**
0.883**
0.402**
0.582**
0.599**
1
K 0.646**
0.227*
0.896**
0.348**
0.644**
0.615**
0.973**
1
** = P<0.01; * = P<0.05, levels of significance.
112
Phytochemical content of different vegetables
Determination of alkaloids content (mg g-1
) in selected vegetables
The results for alkaloids represented significant differences (P≤0.01)
among vegetable types, processing methods and their interaction (Appendix XXIII).
Amaranthus had maximum alkaloids (2.94 mg g-1
), while the lamb quarter ranked second
which was observed to be 0.69 mg g-1
. The minimum alkaloids content of 0.27 mg g-1
was noted in horse radish tree flowers whereas no alkaloids presence was found in
spinach (Table 28). Processing methods indicated significant differences for alkaloids
and showed maximum value of 1.14 mg g-1
in fresh or control vegetables followed by
0.96 mg g-1
in shade dried vegetables. While, minimum value (0.65 mg g-1
) of alkaloids
was observed in curry or cooked vegetables (Table 28). Interaction of processing
methods × vegetables showed highest alkaloids i.e. 3.56 mg g-1
in amaranthus at fresh
condition whereas least (0.07 mg g-1
) was found in horse radish tree flowers after cooking
treatment (Table 28, Figure 23).
113
Table 28. Alkaloids (mg g-1
) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 3.56
a
±0.04
2.85c
±0.004
2.36d
±0.05
2.97b
±0.05
2.98b
±0.03 2.94
A
Lambs quarter 0.96
e
±0.04
0.59hi
±0.004
0.46kl
±0.03
0.65h
±0.04
0.80f
±0.004 0.69
B
Gram leaves 0.74
g
±0.04
0.50jk
±0.006
0.36m
±0.05
0.55ij
±0.04
0.62h
±0.004 0.55
C
Horse radish tree
flowers
0.46kl
±0.04
0.19o
±0.006
0.07p
±0.04
0.25n
±0.04
0.40lm
±0.005 0.27
D
Spinach 0.00
q
±0.00
0.00q
±0.00
0.00q
±0.00
0.00q
±0.00
0.00q
±0.00 0.00
E
Mean 1.14A 0.83
D 0.65
E 0.88
C 0.96
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 23. Graphical representation of the alkaloids (mg g
-1) of selected vegetables
114
Determination of saponins content (mg g-1
) in selected vegetables
The statistical analysis of variance showed a significant (P≤0.01) effect of
vegetable types, processing methods and their interaction on saponins content (Appendix
XXIV). Saponins in lambs quarter revealed higher value of 2.81 mg g-1
followed by 2.19
mg g-1
in gram leaves, while minimum saponins (1.11 mg g-1
) was noted in amaranthus.
There was no presence of saponins in spinach (Table 29). Saponins under the effect of
processing methods displayed highest value of 1.74 mg g-1
in fresh or control vegetables,
followed by 1.58 mg g-1
in shade dried vegetables. The saponins content was lower (0.94
mg g-1
) in curry or cooked vegetables (Table 29). Interaction of processing methods and
vegetables indicated highest saponins of 3.51 mg g-1
in lambs quarter at fresh condition
(control). The lowest saponins i.e. 0.75 mg g-1
was noted from amaranthus after cooking
or curry process (Table 29, Figure 24).
115
Table 29. Saponins (mg g-1
) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 1.650j
±0.05
0.953o
±0.004
0.750p
±0.04
1.050n
±0.03
1.146m
±0.006 1.11
C
Lambs quarter 3.510
a
±0.04
2.516f
±0.004
2.070h
±0.06
2.850c
±0.04
3.110b
±0.002 2.81
A
Gram leaves 2.600
e
±0.04
1.935i
±0.004
1.476k
±0.05
2.68d
±0.03
2.28g
±0.005 2.19
B
Horse radish tree
flowers
0.953o
±0.03
0.413q
±0.005
0.420q
±0.04
1.510k
±0.03
1.390l
±0.005 0.93
C
Spinach 0.00
p
±0.00
0.00p
±0.00
0.00p
±0.00
0.00p
±0.00
0.00p
±0.00 0.00
E
Mean 1.74A 1.16
D 0.94
E 1.61
B 1.58
C
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 24. Graphical representation of the saponins (mg g
-1) of selected vegetables
116
Determination of flavinoids content (mg g-1
) in selected vegetables
Statistical analysis of variance (ANOVA) revealed significant (P≤0.01)
differences in flavinoids under the effect of vegetable types, processing methods and their
interaction (Appendix XXV). The higher flavinoids content (1.21 mg g-1
) was found in
lambs quarter whereas the least flavinoids value was recorded in spinach i.e. 0.07 mg g-1
(Table 30). Among the processing methods, curry or cooked vegetables had minimum
(0.42 mg g-1
) flavinoids. The maximum (0.98 mg g-1
) flavinoids content was recorded in
fresh or control vegetables (Table 30). Interaction of processing methods and vegetables
resulted a maximum value of flavinoids i.e. 1.75 mg g-1
in lambs quarter at fresh
condition. However, the lower flavinoids content (0.02 mg g-1
) was observed from
spinach after curry or cooking process (Table 30, Figure 25).
117
Table 30. Flavinoids (mg g-1
) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 0.85
i
±0.002
0.53o
±0.002
0.24q
±0.002
0.55n
±0.004
0.82j
±0.002 0.60
D
Lambs quarter 1.75
a
±0.002
1.07d
±0.002
0.85i
±0.004
1.14c
±0.02
1.27b
±0.002 1.21
A
Gram leaves 1.27
b
±0.004
0.94g
±0.002
0.66k
±0.002
0.95f
±0.002
1.02e
±0.002 0.96
B
Horse radish tree
flowers
0.95f
±0.95
0.62m
±0.002
0.33p
±0.003
0.64l
±0.003
0.91h
±0.002 0.69
C
Spinach 0.11
r
±0.004
0.05u
±0.001
0.02v
±0.002
0.07t
±0.002
0.10s
±0.004 0.07
E
Mean 0.98A 0.64
D 0.42
E 0.67
C 0.82
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 25. Graphical representation of the flavinoids (mg g
-1) of selected vegetables
118
Determination of phenols content (mg g-1
) in selected vegetables
ANOVA for phenol indicated significant differences among vegetable
types, processing methods and their interaction (Appendix XXVI). Lambs quarter had
maximum value (4.29 mg g-1
) of phenol followed by 3.69 mg g-1
in gram leaves.
However, minimum (0.05 mg g-1
) phenol was observed in spinach (Table 31). Phenol as
influenced by processing methods showed minimum value of 1.58 mg g-1
in curry or
cooked vegetables followed by 1.84 mg g-1
detected in boiled vegetables. However, the
highest phenol (2.66 mg g-1
) was noted from fresh or control vegetables (Table 31).
Phenol content under the interaction of processing methods and vegetables varied
significantly and it was observed that highest value (5.56 mg g-1
) of phenol was in lambs
quarter at fresh condition. However, lowest phenol i.e. 0.012 mg g-1
, 0.01 mg g-1
and 0.02
mg g-1
was obtained from spinach after boiling, cooking and thermal dehydration process,
respectively (Table 31, Figure 26).
119
Table 31. Phenol (mg g-1
) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 0.35
o
±0.002
0.10s
±0.04
0.05t
±0.004
0.15q
±0.002
0.30p
±0.001 0.19
D
Lambs quarter 5.56
a
±0.003
3.51g
±0.003
3.25h
±0.002
3.92e
±0.003
5.22b
±0.002 4.29
A
Gram leaves 4.14
c
±0.004
3.54f
±0.002
2.85k
±0.002
3.93e
±0.004
3.98d
±0.002 3.69
B
Horse radish tree
flowers
3.15i
±0.002
2.07m
±0.002
1.75n
±0.002
2.28l
±0.002
2.97j
±0.002 2.44
C
Spinach 0.11
r
±0.004
0.012u
±0.002
0.01u
±0.002
0.02u
±0.0003
0.10rs
±0.009 0.05
E
Mean 2.66A 1.84
D 1.58
E 2.06
C 2.51
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 26. Graphical representation of the phenols (mg g
-1) of selected vegetables
120
Determination of tanins content (mg g-1
) in selected vegetables
Analysis of variance for tanins revealed significant differences under the
effect of vegetable types, processing methods and their interaction (Appendix XXVII).
Tanins content was higher (0.30 mg g-1
) in amaranthus, while the lambs quarter ranked
second with 0.28 mg g-1
. However, the tanins was lower (0.08 mg g-1
) in horse radish tree
flowers (Table 32). Processing methods indicated lowest value of tanins (0.08 mg g-1
) in
curry/ cooked vegetables followed by 0.14 mg g-1
found from boiled vegetables, whereas
highest (0.31 mg g-1
) tanins was noted from control or fresh vegetables (Table 32).
Interaction of processing methods and vegetables showed significantly maximum tanins
content of 0.48 mg g-1
from amaranthus at fresh condition (control). However, minimum
tanins content i.e. 0.04 mg g-1
was established from horse radish tree flowers after
cooking process (Table 32, Figure 27).
121
Table 32. Tanins (mg g-1
) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 0.48
a
±0.004
0.22de
±0.005
0.11hi
±0.003
0.25d
±0.002
0.44b
±0.004 0.30
A
Lambs quarter 0.45
b
±0.04
0.21e
±0.003
0.09ijk
±0.003
0.23de
±0.002
0.43b
±0.006 0.28
B
Gram leaves 0.18
f
±0.003
0.09ij
±0.0004
0.07jkl
±0.002
0.10i
±0.001
0.13gh
±0.0004 0.11
D
Horse radish tree
flowers
0.14g
±0.002
0.06kl
±0.003
0.04l
±0.003
0.09ijk
±0.02
0.10hi
±0.003 0.09
E
Spinach 0.34
c
±0.003
0.10hi
±0.10
0.08ijk
±0.004
0.11hi
±0.002
0.22e
±0.07 0.17
C
Mean 0.31A 0.14
D 0.08
E 0.15
C 0.26
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 27. Graphical representation of the tanins (mg g
-1) of selected vegetables
122
Correlation matrix (r) of phytochemical content of different vegetables
The relationships among phytochemicals of different vegetables under the
effect of postharvest processing are presented in Table 33. It is obvious from the results
that alkaloids showed a non-significant (P ≥ 0.05) positive relationship with saponins (r =
0.118) and flavinoids (r = 0.147) while a significant negative correlation with phenol (r =
-0.30) and a significant positive association with tannins (r = 0.547) was noted. Similarly,
saponins had a significant and positive correlation with flavinoids (r = 0.932), phenol (r =
0.868) and tannins (r = 0.330). Flavinoids showed a positive and significant correlation
with phenol (r = 0.871) and tannins (r = 0.384). However, phenol and tannins had a non-
significant association.
Table 33. Correlation matrix (r) of phytochemical content of different vegetables
under the influence of processing treatments
Alkaloids Saponins Flavinoids Phenol Tanins
Alkaloids 1
Saponins 0.118
1
Flavinoids 0.147
0.932**
1
Phenol -0.300*
0.868**
0.871**
1
Tanins 0.547** 0.330**
0.384**
0.043
1
** = P<0.01; * = P<0.05, levels of significance.
123
Vitamin content of different vegetables
Determination of β-carotene content (mg 100g-1
) in selected vegetables
Analysis of variance for β-carotene is given in Appendix XXVIII.
Analysis indicated a significant effect of vegetable types, processing methods and their
interaction on β-carotene content. The maximum β-carotene content (2.93 mg 100g-1
)
was observed in spinach, while the lambs quarter ranked second with 2.98 mg 100g-1
.
However, the lowest β-carotene of 0.02 mg 100g-1
was recorded in gram leaves (Table
34). β-carotene content as influenced by processing methods showed lowest value of 0.82
mg 100g-1
from curry or cooked vegetables followed by 1.40 mg 100g-1
from boiled
vegetables, while highest β-carotene of 2.73 mg 100g-1
observed from control/ fresh
vegetables (Table 34). Interactive effect of processing methods × vegetables showed
highest β-carotene (4.93 mg 100g-1
) from spinach at fresh condition. The lowest β-
carotene content i.e. 0.009 mg 100g-1
and 0.008 mg 100g-1
was noted from gram leaves
after boiling and curry process, respectively (Table 34, Figure 28).
124
Table 34. β-carotene content (mg 100g-1
) of different types of vegetables under the
effect of postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 3.28
b
±0.004
0.97h
±0.004
0.54ij
±0.004
1.01h
±0.005
1.09h
±0.004 1.38
B
Lambs quarter 3.46
b
±0.04
3.07c
±0.004
1.77f
±0.04
3.28b
±0.005
3.33b
±0.02 2.98
A
Gram leaves 0.04
k
±0.005
0.009k
±0.002
0.008k
±0.002
0.02k
±0.005
0.03k
±0.003 0.02
D
Horse radish tree
flowers
2.26e
±0.04
0.55ij
±0.003
0.37j
±0.004
0.73i
±0.04
1.45g
±0.005 1.07
C
Spinach 4.60
a
±0.006
2.40e
±0.003
1.40g
±0.004
2.81d
±0.004
3.46b
±0.005 2.93
A
Mean 2.73A 1.40
D 0.82
E 1.57
C 1.87
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 28. Graphical representation of the vitamin A (β-carotene) content (mg
100g-1
) of selected vegetables
125
Determination of vitamin C content (mg 100g-1
) in selected vegetables
Vitamin C content was significantly (P≤0.01) affected by vegetable types,
processing methods and their interaction as shown Appendix XXIX. The results for
vitamin C indicated maximum value of 37.33 mg 100g-1
in gram leaves followed by
35.62 mg 100g-1
in amaranthus as compared to lower vitamin C of 3.42 mg 100g-1
in
horse radish tree flowers (Table 35). Processing methods represented lowest (15.42 mg
100g-1
) vitamin C from curry/cooked vegetables followed by 16.91 mg 100g-1
from
boiled vegetables. However, highest vitamin C content (41.11 mg 100g-1
) was noted from
fresh vegetable samples (Table 35). Interaction of processing methods × vegetables
showed significantly higher vitamin C i.e. 60.74 mg 100g-1
in gram leaves at fresh
condition, while minimum vitamin C of 1.31 mg 100g-1
was recorded from horse radish
tree flowers after curry or cooking process (Table 35, Figure 29).
126
Table 35. Vitamin C (mg 100g-1
) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 56.34
b
±0.04
25.98k
±0.005
23.55m
±0.005
34.67h
±0.004
37.57f
±0.05 35.62
B
Lambs quarter 43.79
c
±0.007
18.11q
±0.004
17.42r
±0.005
22.13n
±0.005
27.41i
±0.005 25.77
C
Gram leaves 60.74
a
±0.004
26.33j
±0.004
24.08l
±0.003
35.50g
±0.004
39.99d
±0.004 37.33
A
Horse radish tree
flowers
6.727u
±0.004
1.977x
±0.005
1.313y
±0.003
3.337w
±0.002
3.793v
±0.005 3.429
E
Spinach 37.95
e
±0.006
12.14s
±0.004
10.75t
±0.004
19.90p
±0.004
21.04o
±0.026 20.36
D
Mean 41.11A 16.91
D 15.42
E 23.11
C 25.96
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 29. Graphical representation of the vitamin C (mg 100g
-1) of selected
vegetables
127
Determination of vitamin B1 content (mg 100g-1
) in selected vegetables
ANOVA for vitamin B1 showed significant differences (P≤0.01) among
vegetable types, processing methods and their interaction (Appendix XXX). Gram leaves
had higher vitamin B1 of 0.159 mg 100g-1
followed by 0.126 mg 100g-1
in lambs quarter,
while the lowest vitamin B1 (0.019 mg 100g-1
) was noted in amaranthus (Table 36).
Vitamin B1 content revealed the lowest (0.054 mg 100g-1
) from curry/ cooked vegetables
whereas the highest vitamin B1 (0.126 mg 100g-1
) was found from fresh vegetables
(Table 36). Interactive effect processing methods × vegetables showed significantly
maximum vitamin B1 content of 0.216 mg 100g-1
in gram leaves at fresh or control
condition (Table 36, Figure 30).
128
Table 36. Vitamin B1 (mg 100g-1
) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 0.026
jkl
±0.005
0.017kl
±0.0005
0.013l
±0.0004
0.018kl
±0.0003
0.024kl
±0.0004 0.019
E
Lambs quarter 0.170
b
±0.04
0.120de
±0.004
0.086fg
±0.004
0.120de
±0.002
0.133cde
±0.006 0.126
B
Gram leaves 0.216
a
±0.004
0.123de
±0.005
0.106ef
±0.003
0.143bcd
±0.004
0.206a
±0.003
0.159A
Horse radish tree
flowers
0.060ghi
±0.04
0.038ijk
±0.004
0.033ijkl
±0.03
0.039ijk
±0.004
0.050hij
±0.03 0.044
D
Spinach 0.156
bc
±0.004
0.038ijk
±0.0005
0.037ijkl
±0.003
0.054hij
±0.004
0.071gh
±0.0005 0.071
C
Mean 0.126A 0.068
C 0.054
D 0.075
C 0.096
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 30. Graphical representation of the vitamin B1 (mg 100g
-1) of selected
vegetables
129
Determination of vitamin B2 content (mg 100g-1
) in selected vegetables
Statistical analysis showed significant differences (P≤0.01) in vitamin B2
under the influence of vegetable types, processing methods and their interaction
(Appendix XXXI). The maximum vitamin B2 (0.317 mg 100g-1
) was recorded in lambs
quarter while minimum of 0.014 mg 100g-1
vitamin B2 was observed in amaranthus
(Table 37). Among processing methods, the lowest value of 0.096 mg 100g-1
vitamin B2
content was observed from curry or cooked vegetables followed by 0.106 mg 100g-1
from
boiled vegetables whereas, high vitamin B2 content (0.184 mg 100g-1
) was found from
fresh vegetables (Table 37). Interaction of processing methods and vegetables
represented highest vitamin B2 content (0.46 mg 100g-1
) in lambs quarter at fresh or
control condition. However, lower vitamin B2 content i.e. 0.008 mg 100g-1
was
determined from amaranthus after curry or cooking (Table 37, Figure 31).
130
Table 37. Vitamin B2 (mg 100g-1
) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 0.016
lm
±0.003
0.011m
±0.0005
0.008m
±0.002
0.013lm
±0.004
0.016klm
±0.0006 0.014
D
Lambs quarter 0.460
a
±0.04
0.276cd
±0.004
0.250d
±0.04
0.290bc
±0.04
0.310b
±0.005 0.317
A
Gram leaves 0.076
hi
±0.004
0.038kl
±0.0004
0.036klm
±0.005
0.046jk
±0.005
0.068ij
±0.0007 0.054
C
Horse radish tree
flowers
0.180e
±0.03
0.101fgh
±0.005
0.086ghi
±0.005
0.113fg
±0.003
0.176e
±0.004
0.132B
Spinach 0.186
e
±0.004
0.103fgh
±0.003
0.096ghi
±0.005
0.126f
±0.004
0.173e
±0.004 0.137
B
Mean 0.184A 0.106
CD 0.096
D 0.118
C 0.150
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 31. Graphical representation of the vitamin B2 (mg 100g
-1) of selected
vegetables
131
Determination of vitamin B3 content (mg 100g-1
) in selected vegetables
ANOVA for vitamin B3 content showed significant differences (P≤0.01)
under the effect of vegetable types, processing methods and their interaction (Appendix
XXXII). The results for vitamin B3 represented highest value (0.962 mg 100g-1
) in lambs
quarter, followed by horse radish tree flowers (0.672 mg 100g-1
), spinach (0.54 mg 100g-
1), amaranthus (0.523 mg 100g
-1) and then gram leaves (0.502 mg 100g
-1) as shown in
Table 38. Different processing methods revealed the lowest vitamin B3 (0.434 mg 100g-1
)
from cooked vegetables whereas the highest value (0.901 mg 100g-1
) of vitamin B3 was
noted from fresh vegetables (Table 38). Vitamin B3 under the interactive effect of
processing methods and vegetables displayed highest value i.e. 1.500 mg 100g-1
in lambs
quarter at fresh or control (Table 38, Figure 32).
132
Table 38. Vitamin B3 (mg 100g-1
) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 0.736
cde
±0.003
0.396h
±0.005
0.366h
±0.004
0.416h
±0.003
0.698de
±0.002 0.523
C
Lambs quarter 1.500
a
±0.45
0.696de
±0.005
0.650e
±0.04
0.850cd
±0.03
1.116b
±0.003 0.962
A
Gram leaves 0.666
e
±0.004
0.426h
±0.004
0.336h
±0.005
0.450h
±0.04
0.629ef
±0.003 0.502
C
Horse radish tree
flowers
0.880c
±0.03
0.619efg
±0.005
0.450h
±0.04
0.640e
±0.04
0.768cde
±0.002 0.672
B
Spinach 0.723
de
±0.005
0.466gh
±0.005
0.366h
±0.004
0.483fgh
±0.005
0.669e
±0.006 0.542
C
Mean 0.901A 0.521
C 0.434
D 0.568
C 0.777
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 32. Graphical representation of the vitamin B3 (mg 100g
-1) of selected
vegetables
133
Correlation matrix (r) of vitamin content of different vegetables
Table 39 indicates relationship among vitamin contents of different
vegetables under the effect of postharvest processing. β-carotene showed a significant
positive relationship with vitamin B2 (r = 0.646) and vitamin B3 (r = 0.553) whereas a
non-significant correlation was obtained with vitamin C (r = 0.091) and vitamin B1 (r =
0.056). Vitamin C also showed a non-significant association with vitamin B2 (r = -0.088)
and vitamin B3 (r = 0.213) whereas a significant correlation was found with vitamin B1 (r
= 0.498). The vitamin B1, vitamin B2 and vitamin B3 were significantly positive
associated with each other as indicated by “r” value which is ranging from 0.342 to
0.766.
Table 39. Correlation matrix (r) of vitamin content of different vegetables under the
influence of processing treatments
β-carotene Vitamin C Vitamin B1 Vitamin B2 Vitamin B3
β-carotene 1
Vitamin C 0.091
1
Vitamin B1 0.056
0.498**
1
Vitamin B2 0.646**
-0.088
0.408**
1
Vitamin B3 0.553**
0.213
0.342**
0.766**
1
** = P<0.01; * = P<0.05, levels of significance.
134
Total solids, total soluble solids, energy value, pH, nitrogen free extract and fatty
acid contents of different vegetables
Determination of total solids (%) in selected vegetables
The total solids content was significantly (P≤0.01) affected by different
types of processing methods, vegetable types and their interaction (Appendix XXXIII).
The values of total solids in amaranthus, lambs quarter, gram leaves, horse radish tree
flowers and spinach were in order of 51.63, 49.08, 50.52, 48.70 and 45.53%, respectively
(Table 40). Among the processing methods, the highest value (93.72%) of total solids
was noted in thermally dehydrated vegetables followed by shade dried (93.01%).
However, minimum of 13.48% total solids was detected in boiled vegetables (Table 40).
Interactive effect of vegetables × processing methods showed greater value of total solids
(95.06%) in horse radish tree flowers under thermal dehydration process, while the least
value of total solids (7.34%) was found in spinach under boiling method (Table 40,
Figure 33).
135
Table 40. Total solids (%) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 18.03
hi
±0.33
16.95hi
±0.31
34.50d
±0.3
94.59a
±0.11
94.11a
±0.15 51.63
A
Lambs quarter 15.92
ij
±0.72
14.54jk
±0.64
28.58f
±0.25
93.58ab
±0.10
92.82ab
±0.11 49.08
C
Gram leaves 17.72
hi
±0.10
15.86ij
±0.13
31.24e
±0.92
94.00a
±0.36
93.78a
±0.13 50.52
B
Horse radish tree
flowers
19.02h
±0.24
12.74kl
±0.54
22.54g
±1.21
95.06a
±0.27
94.16a
±0.22 48.70
C
Spinach 11.24
l
±0.41
7.34m
±0.08
27.53f
±1.13
91.37bc
±0.18
90.16c
±0.12 45.53
D
Mean 16.38C 13.48
D 28.87
B 93.72
A 93.01
A
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 33. Graphical representation of the total solids (%) of selected vegetables
136
Determination of total soluble solids (°Brix) in selected vegetables
Statistical analysis of variance (ANOVA) indicated a significant effect of
vegetable types, processing types and interaction of vegetables × processing (Appendix
XXXIV). The results indicated maximum (2.017°Brix) total soluble solids in spinach
followed by gram leaves (1.971°Brix), amaranthus (1.472°Brix), lambs quarter
(1.05°Brix) and horse radish tree flowers (0.936°Brix) as shown in Table 41. Vegetables
treated with different processing methods displayed significant differences for total
soluble solids. Maximum value of total soluble solids (2.094°Brix) was found in
thermally dehydrated vegetables, while the shade drying method ranked second with
1.828°Brix, whereas lower value of 0.94°Brix total soluble solids was observed in boiled
method (Table 41). Total soluble solids under the interactive effect of vegetable type and
processing type showed higher value of 2.68, 2.66 and 1.963°Brix in gram leaves,
spinach and amaranthus, respectively under thermall dehydration method (Table 41,
Figure 34).
137
Table 41. Total soluble solids (°Brix) of different types of vegetables under the effect
of postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 1.936
e
±0.06
0.936l
±0.05
0.990kl
±0.06
1.963de
±0.02
1.536g
±0.35 1.472
C
Lambs quarter 1.040
k
±0.07
0.550m
±0.02
0.580m
±0.02
1.660f
±0.04
1.420ij
±0.02 1.050
D
Gram leaves 2.030
d
±0.07
1.420ij
±0.03
1.446hij
±0.04
2.680a
±0.06
2.280c
±0.05 1.971
B
Horse radish tree
flowers
0.953l
±0.03
0.413n
±0.03
0.416n
±0.04
1.510gh
±0.05
1.386j
±0.03 0.936
E
Spinach 2.020
d
±0.07
1.420ij
±0.02
1.470ghi
±0.04
2.660a
±0.03
2.516b
±0.05 2.017
A
Mean 1.596C 0.948
D 0.981
D 2.094
A 1.828
B
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 34. Graphical representation of the total soluble solids (°Brix) of selected
vegetables
138
Determination of energy value (Kcal 100g-1
) in selected vegetables
Analysis of variance represented a significant (P≤0.01) effect of
processing methods, vegetable types and their interaction on energy value as indicated in
Appendix XXXV. Energy value in amaranthus, gram leaves, lambs quarter, spinach and
horse radish tree flowers was in order of 150.3, 143.2, 142.1, 139.8 and 130.3 Kcal 100g-
1, respectively (Table 42). Among the processing methods, maximum energy value
(265.8 Kcal 100g-1
) was noted in shade dried vegetables followed by thermally dehdrated
vegetables (261.63 Kcal 100g-1
). However, minimum energy value (41.04 Kcal 100g-1
)
was exhibited in boiled vegetables (Table 42). Interactive effect of vegetables and
processing methods showed lowest energy value (28.41 Kcal 100g-1
) in spinach under
boiling method (Table 42, Figure 35).
Table 42. Energy value (Kcal 100g-1
) of different types of vegetables under the effect
of postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 53.32
f
±0.32
50.43f
±0.75
107.6d
±0.51
268.9ab
±2.10
271.6a
±1.18 150.3
A
Lambs quarter 43.05
fg
±0.92
42.16fg
±0.74
89.45de
±0.89
266.1ab
±0.3
269.7a
±0.51 142.1
AB
Gram leaves 47.21
fg
±0.28
45.16fg
±0.32
92.90de
±1.59
261.98ab
±0.54
269.0a
±0.93 143.2
AB
Horse radish
tree flowers
47.02fg
±0.26
39.06fg
±1.27
75.25e
±1.98
241.5c
±0.46
249.0bc
±1.04 130.3
C
Spinach 38.35
fg
±0.78
28.41g
±0.43
92.93de
±1.36
269.6a
±0.51
269.8a
±0.21 139.8
B
Mean 45.79C 41.04
C 91.63
B 261.63
A 265.8
A
Means within columns and rows followed by same letters are not significantly different at
5% probability level
139
Figure 35. Graphical representation of the energy value (Kcal 100g
-1) of selected
vegetables
Determination of pH value in selected vegetables
Statistical analysis of variance for pH value showed significant differences
(P≤0.01) among vegetable types, processing types and their interaction (Appendix
XXXVI). The higher pH of 7.26 and 7.13 was recorded in lambs quarter and amaranthus,
respectively while the minimum pH of 6.64 was detected in gram leaves (Table 43).
Among the processing methods, boiled vegetables had maximum pH value of 7.202
while the cooked vegetables ranked second with 7.134. The minimum pH (6.827) was
found in samples of thermally dehydrated vegetables (Table 43). Interactive effect of
vegetable type × processing type showed highest pH value of 7.446 in lambs quarter
under boiling process (Table 43, Figure 36).
140
Table 43. pH level of different types of vegetables under the effect of postharvest
processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 7.150
f
±0.04
7.330bc
±0.04
7.240de
±0.04
6.946hi
±0.05
7.026gh
±0.06 7.138
B
Lambs quarter 7.260
cd
±0.02
7.446a
±0.26
7.373ab
±0.014
7.083fg
±0.04
7.156ef
±0.04 7.264
A
Gram leaves 6.660
kl
±0.04
6.820j
±0.04
6.710k
±0.06
6.460m
±0.02
6.580l
±0.04 6.646
D
Horse radish tree
flowers
6.980h
±0.02
7.130f
±0.06
7.010gh
±0.08
6.810j
±0.06
6.880ij
±0.05 6.962
C
Spinach 7.076
fg
±0.07
7.286cd
±0.06
7.340bc
±0.04
6.836j
±0.04
6.973h
±0.03 7.102
B
Mean 7.025C 7.202
A 7.134
B 6.827
E 6.923
D
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 36. Graphical representation of the pH of selected vegetables
141
Determination of nitrogen free extracts (%) in selected vegetables
Analysis of variance for nitrogen free extracts is given in Appendix
XXXVII. Analysis indicated significant differences (P≤0.01) for vegetable types,
processing methods and their interaction. The higher nitrogen free extract was recorded
in amaranthus (28.24%), lambs quarter (27.56%), spinach (26.24%) and gram leaves
(26.04%) as compared to lower nitrogen free extract of 20.28% in horse radish tree
flowers (Table 44). Samples had the highest nitrogen free extract of 55.92 and 53.17% in
shade dried and thermally dehydrated vegetables, respectively. However, the minimum
values of 3.043 and 4.686% nitrogen free extract were noted in fresh and boiled
vegetables, respectively (Table 44). Interactive effect of vegetable type and processing
methods indicated maximum value of nitrogen free extract i.e. 59.03% in lambs quarter
under shade drying process (Table 44, Figure 37).
142
Table 44. Nitrogen free extract (%) of different types of vegetables under the effect
of postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 5.060
efg
±0.76
7.630defg
±1.03
15.94d
±0.68
55.30ab
±1.25
57.28ab
±2.51 28.24
A
Lambs quarter 4.017
efg
±0.51
6.337defg
±1.37
11.66def
±0.28
56.77ab
±0.26
59.03a
±1.07 27.56
A
Gram leaves 2.873
efg
±0.52
5.837efg
±0.37
12.08de
±0.96
53.00abc
±0.27
56.42ab
±0.94 26.04
A
Horse radish tree
flowers
1.600g
±0.38
1.750fg
±0.72
5.783efg
±1.17
43.84c
±0.26
48.46bc
±0.93 20.28
B
Spinach 1.663
g
±0.44
1.877fg
±0.17
12.29de
±0.95
56.96ab
±0.51
58.43ab
±0.75 26.24
A
Mean 3.043C 4.686
C 11.55
B 53.17
A 55.92
A
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 37. Graphical representation of the nitrogen free extract (%) of selected
vegetables
143
Determination of total fatty acids (%) in selected vegetables
Statistical analysis showed that total fatty acids were significantly
(P≤0.01) affected by vegetable types, processing methods and interaction of vegetables x
processing (Appendix XXXVIII). Total fatty acids were higher (2.184%) in horse radish
tree flowers, while the spinach ranked second with 2.096% total fatty acids. However, the
lowest (1.319%) total fatty acids were observed in lambs quarter (Table 45). Total fatty
acids under the effect of processing methods indicated significant differences and showed
a maximum value of total fatty acids (2.640%) in curry or cooked vegetables followed by
thermally dehydrated (1.898%), while minimum value (1.052%) of total fatty acids was
recorded from boiled samples of vegetables (Table 45). Interactive effect of vegetables
and processing type resulted highest total fatty acids (3.08%) in horse radish tree flowers
at cooking or curry process. However, least value (0.68%) of total fatty acids was
observed in gram leaves under boiling method (Table 45, Figure 38).
144
Table 45. Total fatty acids (%) of different types of vegetables under the effect of
postharvest processing methods
Vegetables
Processing methods
Mean Fresh
(control) Boiled Curry
Thermally
dehydrated
Shade
dried
Amaranthus 1.720
defghi
±0.14
0.880kl
±0.18
2.720ab
±0.21
2.040cde
±0.22
1.846cdefgh
±0.24 1.841
B
Lambs quarter 1.00
jkl
±0.22
0.700l
±0.17
2.280bc
±0.22
1.360hijk
±0.14
1.256ijk
±0.2 1.319
C
Gram leaves 1.280
ijk
±0.12
0.680l
±0.2
2.200cd
±0.18
1.610efghi
±0.14
1.593efghi
±0.16 1.472
C
Horse radish tree
flowers
1.920cdefg
±0.11
1.520fghi
±0.21
3.080a
±0.22
2.280bc
±0.18
2.120cd
±0.18 2.184
A
Spinach 1.880
cdefg
±0.1
1.480ghij
±0.22
2.920a
±0.14
2.200cd
±0.14
2.00cdf
±0.14 2.096
A
Mean 1.560C 1.052
D 2.640
A 1.898
B 1.763
BC
Means within columns and rows followed by same letters are not significantly different at
5% probability level
Figure 38. Graphical representation of the total fatty acid (%) of selected vegetables
145
Correlation matrix (r) of Nitrogen free extract, energy value, fatty acid, pH, total
solids and TSS of different vegetables
The relationships among nitrogen free extract, energy value, fatty acid,
pH, total solids and total soluble solids of vegetables under the influence of postharvest
processing are shown in Table 46. The relationship showed that total solids was
significantly and positively correlated with total soluble solids (r = 0.561), energy (r =
0.992) and nitrogen free extract (r = 0.968) whereas a significant negative correlation was
observed with pH (r = -0.469). Fatty acid imparted a non-significant correlation with total
solids (r = 0.149), pH (r = -0.040), total soluble solids (r = -0.004), energy (r = 0.178) and
nitrogen free extract (r = -0.103). Nitrogen free extract showed a significant positive
association with total soluble solids (r = 0.572) and energy (r = 0.998) while non-
significantly and negatively associated with pH (r = -0.403). Energy value indicated
significant negative association with pH (r = -0.442) and positive association with total
soluble solids (r = 0.570). However, pH showed significant relationship with total soluble
solids (r = -0.620).
146
Table 46. Correlation matrix (r) of Nitrogen free extract, energy value, fatty acid,
pH, total solids and TSS of different vegetables under the influence of
processing treatments
Total solids PH TSS Energy NFE Fatty acid
Total solids 1
PH -0.469**
1
TSS 0.561**
-0.620**
1
Energy 0.992**
-0.442**
0.570**
1
NFE 0.968**
-0.403**
0.572**
0.988**
1
Fatty acid 0.149
-0.040
-0.004
0.178
0.103
1
** = P<0.01; * = P<0.05, levels of significance.
Determination of total chlorophyll content (mg g-1
) in selected vegetables
Analysis of variance for total chlorophyll content is given in Appendix
XXXIX. The results in Table 47 (Figure 39) show the chlorophyll content of amaranthus,
gram leaves, horse radish tree flower, lambs quarter and spinach leaves. The purpose of
chlorophyll determination was to ensure the quality of the vegetable. The highest total
chlorophyll content (a + b) was detected in lambs quarter (3.19 mg g-1
), followed by
spinach (1.88 mg g-1
), amaranthus (1.850 mg g-1
), gram leaves (1.504 mg g-1
) and horse
radish tree flowers (0.048 mg g-1
).
147
Table 47. Chlorophyll content of fresh vegetables selected in the present study
Vegetables Chlorophyll a
(mg g-1
)
Chlorophyll b
(mg g-1
)
Total chlorophyll
(mg g-1
)
Amaranthus 1.306b ± 0.005 0.543
c ± 0.009 1.850
c ± 0.006
Lambs quarter 1.548a ± 0.003 1.650
a ± 0.008 3.199
a ± 0.004
Gram leaves 1.147c ± 0.004 0.357
d ± 0.002 1.504
d ± 0.007
Horse radish tree
flowers 0.027
d ± 0.005 0.021
e ± 0.009 0.048
e ± 0.004
Spinach 1.311b ± 0.005 0.577
b ± 0.007 1.888
b ± 0.008
Mean values ± SD triplicate determinations. Mean values within a column with different
superscripts are significantly different at P<0.05
Figure 39. Graphical representation of the total chlorophyll (%) of selected
vegetables
148
Sensory evaluation of selected vegetables
Sensory evaluation of uncooked vegetables
The data presented in table 48 (Figure 40- 44) shows the five point scale
of 5 raw or uncooked non-traditional vegetables, in which different parameters were
studied including appearance, color, odor, texture, taste and overall acceptability. Horse
radish tree flowers obtained highest scores in appearance, color, odor, texture, taste,
overall acceptability and purchase i.e. 4.90, 4.70, 4.00, 3.90, 3.50, 3.80 and 3.80. The
second vegetable securing highest scores was gram leaves followed by amaranthus,
lambs quarter and spinach. The analysis of variance for sensory analysis of uncooked
vegetables is given in Appendix XLI.
Table 48. Five point scale sensory scores of raw or uncooked vegetables
Parameters Amaranthus
Lambs
quarter
Gram
leaves
Horse
radish tree
flowers
Spinach
Appearance 3.90a ±0.73 3.70
a ±0.82 4.10
a ±0.87 4.90
b ±0.31 3.60
a ±1.17
Color 4.00ab
±0.81 3.60a ±0.84 4.00
ab ±0.81 4.70
b ±0.48 3.60
a ±1.07
Odor /
Aroma 3.70
a ±0.67 3.20
a ±0.91 3.60
a ±1.26 4.00
a ±0.47 3.30
a ±0.94
Texture
rating 3.60
ab ±0.69 3.10
a ±0.73 3.80
ab ±0.78 3.90
b ±0.56 3.30
ab ±0.94
Taste/ flavor 2.90a ±1.10 3.00
a ±0.94 3.20
a ±1.13 3.50
a ±0.85 3.20
a ±1.13
Overall
acceptability 3.50
a ±0.85 3.40
a ±0.84 3.50
a ±0.97 3.80
a ±0.78 3.60
a ±0.96
Purchase 3.20a ±1.31 3.10
a ±0.87 3.60
a ±1.17 3.80
a ±0.91 3.50
a ±1.19
Values are expressed as mean (n=10); Values with different superscripts down the rows
are significantly different from each other at p<0.05
149
Figure 40. Spider chart showing five point scale sensory scores of uncooked
amaranthus vegetable
Figure 41. Spider chart showing five point scale sensory scores of uncooked lambs
quarter vegetable
150
Figure 42. Spider chart showing five point scale sensory scores of uncooked gram
leaves vegetable
Figure 43. Spider chart showing five point scale sensory scores of uncooked horse
radish tree flowers vegetable
151
Figure 44. Spider chart showing five point scale sensory scores of uncooked spinach
vegetable
Sensory evaluation of cooked vegetables
The scores of all the attributes showed that samples cooked by different
methods were highly acceptable (Table 49, Figure 45-49). Analysis of variance for total
chlorophyll content is given in Appendix XLII. Traditionally cooked lambs quarter and
gram leaves retained original color and thus obtained the highest scores in appearance i.e.
3.70 and 3.90, respectively. The lambs quarter vegetable retained pleasant odor with the
score of 3.50, as compared with horse radish tree flowers, gram leaves, amaranthus and
spinach (3.30, 3.20, 3.10 and 3.10, respectively). Gram leaves and horse radish tree
flowers secured the same rating for texture (3.70), purchase (4.20) and overall
acceptability (3.40).
152
Table 49. Five point scale sensory scores of cooked vegetables
Parameters Amaranthus Lambs
quarter
Gram
leaves
Horse
radish tree
flowers
Spinach
Appearance 3.60a ±1.07 3.70
a ±1.25 3.70
a ±0.94 3.60
a ± 1.26 3.40
a ±1.07
Taste 3.20a ±0.91 3.90
ab ±0.99 3.50
ab±0.52 3.50
ab ±0.97 4.10
b ±0.56
Odor/ Aroma 3.10a ±0.73 3.50
a ±0.70 3.20
a ±0.91 3.30
a ±0.94 3.10
a ±0.73
Texture
rating 3.50
a ±0.85 3.00
a ±1.05 3.70
a ±0.67 3.70
a ±0.82 3.00
a ±0.94
Overall
acceptability 3.30
a ±1.25 3.80
a ±1.22 3.40
a ±
0.84 3.40
a ±0.69 3.00
a ±1.24
Purchase 3.90a ±0.99 4.10
a ±0.87 4.20
a ±0.91 4.20
a ±1.13 3.90
a ±0.99
Values are expressed as mean (n=10); Values with different superscripts down the rows
are significantly different from each other at p<0.05
Figure 45. Spider chart showing five point scale sensory scores of cooked
amaranthus vegetable
153
Figure 46. Spider chart showing five point scale sensory scores of cooked lambs
quarter vegetable
Figure 47. Spider chart showing five point scale sensory scores of cooked gram
leaves vegetable
154
Figure 48. Spider chart showing five point scale sensory scores of cooked horse
radish tree flowers vegetable
Figure 49. Spider chart showing five point scale sensory scores of cooked spinach
vegetable
155
Principal component analysis of nutritional characteristics of different vegetables
Quality of vegetables can be affected by several factors (pre-harvest &
post-harvest factors) and the nutritional characteristics of different vegetables vary
differently. This situation leads to search for linear combinations which are optimal in
some sense. These linear combinations are computed by the methods called “Principle
Component Analysis”. The principal component analysis transforms the original
variables into new axes, or principal components, which are orthogonal, so that the data
presented in those axes are uncorrelated with each other; therefore, PCA provides
information for interpretation and better understanding of the most meaningful
parameters which describes the whole data set through data reduction with a minimum
loss of the original information (Berrueta et al., 2007; Cam et al., 2009). The first
principal component covers as much of the variation in the data as possible. The second
principal component is orthogonal to the first and covers as much of the remaining
variation as possible, and so on. The results obtained in PCA are interpreted in the
following sections:
Component analysis
Table 50 shows the eigenvalue and total variance explained for our factor
solution. There are thirty-four variables used in the sample. It is quite clear from the table
that the first seven components has their eigenvalues over 1 and are large enough to be
retained. This is based on Chatfield and Collin (1980) assumption which stated that
components with an eigenvalue of less than 1 should be eliminated. The result further
156
revealed that the first seven components contributed 94.79% (that is their cumulative
variance) of the variability among the observed variables. This indicates that the variance
of the 34 observed variables had been accounted for by these 7 extracted components
(principle components). Component 1, 2, 3, 4, 5, 6 and 7 explained 46.98, 14.39, 11.65,
8.31, 5.91, 4.31 and 3.24% of the total variation, respectively. It can also be seen from the
table that the initial eigenvalues and the extracted eigenvalues are exactly same which is
evident of the validity of the principal component analysis.
157
Table 50. Extraction of components by using eigen values and variability percentage
Component
Initial Eigenvalues Extraction Sums of Squared Loadings
Total % of
Variance Cumulative % Total
% of
Variance
Cumulative
%
1 15.97 46.97 46.97 15.97 46.96 46.97
2 4.89 14.38 61.36 4.89 14.36 61.32
3 3.96 11.65 73.01 3.96 11.64 73.01
4 2.82 8.31 81.32 2.82 8.31 81.39
5 2.01 5.91 87.24 2.01 5.91 87.22
6 1.46 4.30 91.54 1.46 4.30 91.59
7 1.10 3.24 94.79 1.10 3.24 94.70
8 0.41 1.21 96.00
9 0.31 0.93 96.94
10 0.21 0.62 97.56
11 0.17 0.50 98.07
12 0.15 0.46 98.53
13 0.13 0.40 98.94
14 0.09 0.28 99.22
15 0.07 0.21 99.43
16 0.05 0.17 99.60
17 0.03 0.10 99.70
18 0.03 0.08 99.79
19 0.02 0.08 99.87
20 0.01 0.04 99.92
21 0.01 0.03 99.95
22 0.007 0.02 99.97
23 0.005 0.01 99.98
24 0.002 0.007 99.99
25 0.001 0.004 99.99
26 0.001 0.002 99.99
27 0.00 0.00 100.00
28 0.00 0.00 100.00
29 9.067E-16 2.667E-15 100.00
30 3.683E-16 1.083E-15 100.00
31 4.244E-17 1.248E-16 100.00
32 -3.010E-16 -8.854E-16 100.00
33 -6.149E-16 -1.809E-15 100.00
34 -8.781E-16 -2.583E-15 100.00
158
Scree plot
The scree plot of the eignvalues of observed components is depicted in
Figure 50. The horizontal axis shows the number of total components (34) while on
vertical axis, the eigenvalues are plotted. It can be clearly seen from the figure that first
seven eigenvalues are greater in magnitude whereas after these seven values the change
in eigenvalue is very small i.e., less than one. Based on the large magnitude of the first
seven eigenvalues it can be easily concluded that seven factors are well enough to
account for the data variability.
Figure 50. Scree plot of the eigenvalues
159
Principal component loadings
The calculated component loadings are shown in Table 51. The
component loading is a matrix of correlation between components and variables. Factor
scores or “factor loadings” indicate how each “hidden” factor is associated with the
“observable” variables used in the analysis. The first column is the correlation between
the first component and each variable, the second column is the correlation between the
second component and each variable and so on.
Classifying the component loading according to Liu et al. (2003) the
loading values greater 0.75 signifies “strong”, the loading with absolute values between
0.75 and 0.50 indicate “moderate” while loading values between 0.50 and 0.30 denote as
“weak”. Using this classification, the first principal component axis had strong loading
for moisture, total solid, ash, fiber, carbohydrate, nitrogen free extract, energy value,
acetic acid, citric acid, oxalic acid, tartaric acid, copper, iron, zinc, manganese, calcium,
sodium and potassium. The second principal component axis weighed strong saponins,
flavinoids, phenol and vitamin B3 while tannins content had strong loadings in the third
principal component axis. All variables in component 4, 5, 6 and 7 explained weak and
moderate loadings. It can be seen that as these correlations become weak as the number
of principal component increases.
160
Table 51. Analysis of component score coefficient matrix
Parameters Component
1 2 3 4 5 6 7
Moisture -0.97 -0.007 0.173 -0.013 0.09 0.05 -0.01
Total solid 0.97 0.007 -0.173 0.013 -0.09 -0.05 0.01
Ash 0.94 -0.04 0.181 0.154 -0.07 0.006 0.03
pH -0.14 0.24 0.624 0.032 -0.09 0.28 -0.60
Total soluble solids 0.65 0.04 0.106 0.146 -0.13 0.31 0.55
Fiber 0.84 -0.01 -0.118 0.026 -0.08 -0.16 0.16
Fat 0.09 -0.25 -0.514 0.305 0.56 0.38 0.20
Total fatty acids -0.02 -0.11 -0.422 0.223 0.69 0.41 -0.13
Protein 0.24 0.28 -0.544 0.656 -0.004 0.11 0.06
Carbohydrate 0.95 0.01 -0.181 -0.060 -0.12 -0.06 -0.02
Nitrogen free extract 0.94 0.02 -0.185 -0.072 -0.12 -0.04 -0.05
Energy value 0.95 -0.002 -0.253 -0.002 -0.05 -0.01 -0.00
Acetic acid 0.93 -0.03 -0.098 -0.135 -0.20 0.06 -0.06
Citric acid 0.93 -0.03 -0.098 -0.135 -0.20 0.06 -0.06
Oxalic acid 0.93 -0.03 -0.098 -0.135 -0.20 0.06 -0.06
Tartaric acid 0.93 -0.03 -0.098 -0.135 -0.20 0.06 -0.06
Copper 0.79 0.09 0.311 -0.206 0.36 0.13 -0.17
Iron 0.82 -0.14 0.433 -0.059 0.30 -0.007 -0.07
Zinc 0.88 0.03 0.228 0.297 0.17 0.08 -0.06
Manganese 0.81 -0.08 0.417 -0.031 0.36 -0.03 -0.06
Calcium 0.86 0.11 0.045 -0.133 0.33 -0.25 0.00
Magnesium 0.51 -0.35 0.399 0.558 0.02 -0.23 0.13
Sodium 0.96 -0.007 -0.162 -0.033 0.001 0.06 -0.06
Potassium 0.96 -0.008 -0.140 -0.069 0.05 0.06 -0.12
Alkaloids 0.12 -0.08 0.716 0.630 0.05 -0.11 0.02
Saponins 0.05 0.89 -0.129 0.295 0.12 -0.19 -0.08
Flavinoids 0.04 0.91 -0.034 0.332 0.02 -0.19 -0.03
Phenol 0.00 0.87 -0.433 0.111 0.02 -0.11 -0.09
Tanins 0.22 0.48 0.767 0.076 0.09 0.02 0.16
Vitamin A 0.04 0.11 0.421 -0.717 0.05 0.35 0.28
Vitamin C 0.03 0.42 0.491 0.393 -0.33 0.51 0.06
Vitamin B1 -0.05 0.74 -0.243 -0.056 -0.31 0.45 -0.05
Vitamin B2 0.04 0.69 -0.033 -0.545 0.40 -0.04 0.03
Vitamin B3 0.09 0.79 0.217 -0.269 0.14 -0.21 0.31
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Component correlation analysis
Correlation coefficients between the seven components of the PCA are
shown in the Table 52. It could be observed from this table that mostly correlation
between any two components is very weak and even for some components these values
are found fairly close to zero which show that components are uncorrelated. The
uncorelatedness of components is one of the basic assumptions of PCA. There are
negative correlations between component-II and component-III. Likewise, component-I
is negatively correlated with component-VI and VII. The observed correlation of
component-II with components III, V and VII is nearly 0. Among all the observed
correlations, the highest value was reported between component-I and component-III.
Table 52. Component correlation matrix
Components 1 2 3 4 5 6 7
1 1
2 0.07 1
3 0.27 -0.04 1
4 0.19 0.17 0.23 1
5 0.20 0.06 0.17 0.004 1
6 -0.07 0.15 -0.13 -0.22 -0.18 1
7 -0.09 0.03 0.21 0.25 -0.05 -0.18 1
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3D component plot
The following figure shows the 3D plot of components in rotated space. It
can be inferred from the Figure 51 that three variables that had high loading were
assumed to belong with component-I i.e., alkaloid, moisture and vitamin C. It can be seen
that most of the variables (29) belong to component-II with the exception of TSS and
vitamin A which belong to component-III.
Figure 51. 3D component plot of the nutritional data of selected vegetables
163
CHAPTER-V
DISCUSSION
The consumption of nontraditional vegetables in the form of food was
investigated in three locations of district Mirpurkhas and studied the nutritional
composition of selected wildly grown nontraditional and commercial vegetables after
subjecting to boiling, cooking curry, shade drying and thermal dehydration treatments in
order to know the effect of processing on the nutrient content of vegetables as compared
to raw (uncooked). The results obtained are discussed in the following sections:
Perception of non-traditional vegetable use by selected respondents
Percent frequency data in Table 6 (Figure 4) shows respondent’s
perception about utilization of nontraditional leafy vegetables. It has been observed from
the survey that gram leaves were the most popular non-traditional vegetable eaten
frequent or occasionally by 82% respondents only 18% respondents never tasted or do
not know this vegetable. Next popular vegetables which majority of respondent never
tasted or did not know included amaranthus and lambs quarter. About 62% respondents
never tasted or do not know horse radish tree flowers as vegetable while 38% respondents
answered they eat frequent or occasionally.
The survey was meant to highlight the abundant nontraditional
underutilized vegetables in Sindh province of Pakistan and its environments and also to
164
serve as a tool for alleviating the difficulty in getting these nontraditional vegetables for
their required usage. In addition, the survey was also for the transfer of knowledge on
food security, health and poverty alleviation, as nontraditional vegetables play a crucial
role in food security due to high nutritional value of urban and rural communities
(Seema, 2015). These nontraditional vegetables are also valuable sources of energy and
micronutrients in the diets of the communities (Grivetti and Ogle, 2000). Further, they
serve as income sources to the small farmers and may be marketed locally, provincially
and even globally (Hoeschle-Zeledon and Bordoni, 2003). The range of these species
covered is wide, including plants that provide stimulants, spices, medicines, fibers,
tubers, roots, oils, nuts, leaves, grains and fruits (Sheikh and Javed, 2007). Some of these
species might be broadly distributed all around, however are confined to a more local
production and consumption. Many nontraditional vegetables are grown for oil, grain,
fiber, food and as source of medicine play a major role in the subsistence of local people
and frequently are of special medicinal, cultural and social value (Jain and Gupta, 2013).
Nontraditional vegetables typically do not meet modern standards for
uniformity and other characteristics as they have been neglected by breeders from the
private, public sectors (Stamp et al., 2012) and less competitive in marketplace compared
with commercial crops (Jackson et al., 2007; Frison et al., 2011; McCouch, 2013). Apart
from their medicinal, cultural and commercial value, nontraditional vegetables are also
considered significant for sustainable food production as they decrease the influence of
production systems on the environment (De-la-Pena et al., 2011; Hughes and Ebert,
2013). These plants can be incorporated in commercial crop plants in future and will tend
165
to minimize food scarcity as well as economy in tribal areas for their livelihood and help
in regeneration of barren lands. These plants can be incorporated in commercial crop
plants in future and will tend to minimize food scarcity as well as economy in tribal areas
for their livelihood and help in regeneration of barren lands (Bello et al., 2015).
Effect of processing methods on nutritional composition of vegetables
The proximate composition of fresh, thermally dehydrated, curry, shade
dried and boiled amaranthus, gram leaves, horse radish tree flowers and spinach using
different methods revealed variations in the composition (Table 7-12, Figure 5-10). The
overall results differed for each processing treatment. It was observed that moisture
content was maximum in boiled samples of spinach, horse radish tree flowers, lambs
quarter, gram leaves and amaranthus (92.66, 87.26, 85.46, 84.13 and 83.05%). However,
in fresh samples the maximum moisture ontent was found in spinach followed by lambs
quarter, gram leaves, amaranthus and hors radish tree flowers (88.76, 84.08, 82.28, 81.96
and 80.98%) and minimum moisture was observed in thermally dehydrated samples
(Table 5, Figure 4). The spinach vegetable was recorded with highest moisture content
which means that spinach is highly perishable which cannot be stored for long time
duration. Generally, variations observed in proximate composition could be caused by
variations in the used ingredients or preparation methods (Al-Faris, 2017).
The present results are in agreement with the results of Satter et al. (2016)
who reported the moisture contents of the nontraditional vegetables like Dhekishak,
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Helencha, Kalmishak, Patshak and Shapla stem to be 90.37, 87.60, 90.12, 86.81 and
94.36%, respectively. These results were very close to the moisture contents of some wild
edible and commonly used vegetables in Pakistan (Imran et al., 2007; Hussain et al.,
2011). Hussain et al. (2010) also stated that moisture contents varied in different wild
vegetables investigated by them. Hanif et al. (2006) and Das et al. (2009) concluded that
green leafy vegetables had higher moisture content and were in line with the findings of
Saidu and Jideobi (2009) who recorded highest moisture contents at reproductive stages
in leaves. Hussain et al. (2009b) also reported high moisture contents in Allium sativum
(67.66 %) and Valeriana officinalis (6.82 %) which were lower than observed in the
findings. Adnan et al. (2010) reported high moisture contents in Bupleurum falcatum,
Forsskalea tenacissima, Lavendula angustifolia, Valeriana officinalis and Otostegia
limbata and their results are in conformity with the present results. According to AOAC
(1995) low moisture content signifies high food value. The high moisture levels in the
polluted vegetables suggest that the vegetables analyzed may not be stored for a long
time due to high water activity (Gbadamosi, 2011). Water also provide medium for
water-soluble enzymes and co-enzymes required during metabolism of vegetables
(Ihenacho, 2009). However, increased moisture may add and cause quality deterioration
as the samples studied may be prone to bacterial attack during storage (Onyeike et al.,
2003). It has also been reported which microorganisms that cause spoilage are known to
thrive in foods containing high moisture content (Emebu and Anyika, 2011).
Ash content is the index of the total mineral content of any sample. The
nontraditional vegetables represented in Table 8 (Figure 6) contained high amounts of ash
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that indicated the vegetables were rich in minerals and could provide a considerable
amount of mineral elements in our diet. The ash content (total minerals) in respective
vegetables ranged from 1.227 – 10.56% for amaranthus, 1.187 – 9.507% for lambs
quarter, 1.213 – 10.43% for gram leaves and 0.487 – 16.15% for horse radish tree
flowers. However, the ash content for spinach vegetable was noted 0.507 to 8.680%. The
results of the present study showed that nontraditional vegetables are rich in total mineral
content as compared with commercial vegetable (spinach). In earlier studies, ash content
of nontraditional edible plants has been reported between 0.65 and 26.70% (Demir 2006;
Kagale and Sabale, 2014; Kalita et al., 2014; Tuncturk and Ozgokce, 2015). However,
Roe et al. (2013) reported that the ash content of the wild plants examined were
considerably higher than the commercial vegetables (0.4 - 2.0%). The higher ash content
as compared to commonly available vegetables like lettuce (0.4% DM) and spinach
(0.7% DM) were also reported by Salazar et al. (2006). The high ash content of leaves
may be due to its mineral content (Shukla et al., 2001). Gafar et al. (2011) reported the
ash content of chancapiedra plant to be up-to 5.55% but Nwaogu et al. (2000) revealed
19.61% in Amaranthus hybridus. P. mildbraedii had the highest ash (19.72%) content
(Okon and James, 2015). Orhuamen et al. (2012) found 10.4% for Telfairia occidentalis
while in Talinum triangulare, they reported as ash percentage to be 8.85%.
Protein contents vary according to climatic and habitat conditions
(Cheema et al., 2011). The protein content in Table 9 (Figure 7) was observed greater in
thermally dehydrated gram leaves (7.56%) as compared to other nontraditional
vegetables and in spinach low protein content was observed (1.04% in boiled sample).
168
The data of Satter et al. (2016) also showed that the vegetables are rich sources of protein
which can encourage their use in human diets and might be helpful to contain protein
energy malnutrition. As for as crude protein is concerned, Hanif et al. (2006) recorded
0.9% to 2.1 % protein contents in the selected vegetables. Cheema et al. (2011) reported
high concentration of crude protein in leaves of Morus alba, which happened to be best
source of protein in ruminant feeding. They also stated that differences in crude protein
were due to differences of capability of plants to accumulate protein. This is also true in
this study whereby there were differences in amount of protein among the plants.
Yao et al. (2000) also stated that Morus alba is a best source of protein for
ruminants. Adenipekun and Oyetunji (2010) observed little differences between Vigna
unguiculata (23%) and Arachis hypogea (24%) and this agrees with the findings in some
cases, in this study. Hussain et al. (2010) also found that Sonchus asper and Melia
azadrichta had the highest concentration of protein. Barua et al. (2015) observed the
crude protein content of different plant species in descending order in Drymaria cordata
(20.57%) followed by Homalomena aromatica (20.5%), Elsholtzia communis (16.19%),
Zanthoxylum alatum (10.94%), Clerodendrum indicum (7.88%) and Gnetum gnemon
(6.7%). Hussain et al. (2009a) also noted 6.4% protein in ginger. Shah et al. (2009) stated
that protein rich plants had 23- 33% protein, whereas the present investigation reported
moderate level of protein in analyzed nontraditional plants. The results also differ of from
those of other workers (Hameed et al., 2008; Adnan et al., 2010; Hussain et al., 2010). It
was noted that the local nontraditional plant species consumed as leafy vegetables
169
contained significantly higher amounts of protein than the commercially cultivated leafy
vegetables (Geeta and Sharma, 2015).
Umar et al. (2007) reported protein content of water spinach up to 6.30 %.
Van Wyk (2005) and Odhav et al. (2007) determined the values of protein for Lambs
quarter (4.4%), Amaranthus hybridus (3.5%) and Galinsoga parviflora (3.29%). The
protein contents of the wild plants in this study are relatively comparable to those
obtained by El-Amier and Ejgholi (2014) on Atriplex halimus (14.79%), Limonium
pruinosum (12.38%) and Limoniastrum monopetalum (14.15%), but lower than values
reported by Zahran and El-Amier (2013) on Bassia indica (9.25%), Arthrocnemum
macrostachyum (5.34%) and Halocnemum strobilaceum (9.44%) and Stanacev et al.
(2010) on Medicago sativa and Trifolium alexandrinum. The presence of high protein
indicates nutritional superiority over other consumable crops (Gopalan et al., 2004). Very
high protein content in nontraditional vegetables indicated that the species can be a very
good source of protein as well (Barua et al., 2015). The high protein content of seeds
makes it a good body building food for growth and repair of worn out cells and tissues
specially in children (Chadare et al., 2009).
Fat in food including essential fatty acids and vitamins is considered as a
main source of energy. The crude fat content of the curry samples of horse radish tree
flowers (3.85%) vegetable was higher than other selected vegetables. While in fresh
samples the fat content was found 2.15, 1.25, 1.60 and 2.40% for amaranthus, lambs
quarter, gram leaves and horse radish tree flowers. The fat content of fresh spinach was
170
recorded 2.35% (Table 10, Figure 8). The fatty acid content was recorded higher in curry
samples of horse radish tree flowers (3.08%) followed by spinach (2.92%), amaranthus
(2.720%), lambs quarter (2.280%) and gram leaves (2.200%). The results revealed that
nontraditional vegetables are rich sources of energy as compared with cultivated
vegetable spinach (Table 45, Figure 38). The values of the present study are much higher
as compared with the fat content (0.21- 0.45%) of some leafy vegetables in Nigeria
(Onwordi et al., 2009) and are similar to the fat content (2.00 and 3.01%) of some wild
vegetables in Nigeria and Pakistan (Nkafamiya et al., 2010; Hussain et al., 2011; Khan et
al., 2013).
Crude fats and oils are the part of a complex organic material that is
soluble in ether. It chiefly consists of fats and fatty acids. It is a measure of the fat or oil
(lipid) of plant which is considered as medicinal or nutritious feed and extremely rich
sources of energy. Oils usually impede microbial fermentation. Ruminant diets usually
contain to about 4% fat. The results of this study are in line with Coskun et al. (2004),
Cherney and Cherney (2005) and Hussain and Durrani (2009). Ayuba et al. (2011) who
reported crude lipid content as 6% in roots and 15.52% in the seed of Datura innoxia, as
in the present study. The low level of fats contents may be of benefit to individuals
suffering from hyper lipidaemia because of the role of fat in potentiating risk of
developing certain kinds of cancer, heart disease and diseases associated with damage of
coronary artery (Onunogbu, 2002). Fat also is major determinant of palatability of food
(Antia et al., 2006). The leaves of Leptadenia hastata contain 5.0% crude fat
(Yirankinyuki et al., 2015) which is the same with that of Indigofera astragalina (Gafar
171
et al., 2011). The crude fat content ranges in plants in between 0.31- 1.27% and crude
fiber 7.31- 20.0%. Presence of low fat can be recommended for individuals suffering
from obesity (Barua et al., 2015).
Vegetables are also rich sources of fiber which is an important component
in preventing overweight, constipation, diabetes, increase of serum cholesterol, risk of
heart diseases, breast/colon cancers and hypertension, etc. (Koca et al., 2015). The crude
fiber of the nontraditional vegetables represented in Table 11 (Figure 9) was highest in
thermally dried samples of horse radish tree flowers (13.35%) followed by gram leaves
(10.50%), amaranthus (10.383%), lambs quarter (10.15%) and spinach (9.750%).
Whereas, the fiber content in spinach was noted lowest as compared with nontraditional
vegetables. The findings are closely similar to the other nontraditional edible plants and
commonly consumed vegetables in Pakistan (Hussain et al., 2011; Shad et al., 2013).
Fiber is a nutrient of diet that is necessary for digestion and promoting soft stools for
effective elimination (Vadivel and Janardhanan, 2005). The content of fiber in the wild
vegetables used in the study can encourage their use in the human diet to fulfill the RDA
of fiber. The crude fiber is the organic residue remaining after digestion with acid and
base residues. The fibrous elements are an important constituent of balanced diet that
decreases blood cholesterol level, heart risks, colon cancer and diabetes (Ishida et al.,
2000). Belewu and Babalola (2009) stated that crude fibers can be used for useful
purposes if treated with microorganisms.
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Hussain et al. (2010) estimated fibers varied from 9.5 to 12.12% in
selected nontraditional plants. This range is similar to the findings in this study. Hameed
et al. (2008) reported moisture, ash, crude fiber, proteins, fats and oils, and carbohydrates
contents in Rumex hastatus, R. dentatus and R. nepalensis (Polygonaceae). Their findings
also support the findings in the study. Aberoumand (2012) reported that Solanum indicum
contained 8.00% crude fiber showing the variation from the present study which may
have been due to different soil and environmental factors. Fiber is known to decrease the
risk of obesity (Maki et al., 2012) and plays an important role in the body, to help
maintain a healthy digestive tract, remove potential carcinogens from the body and keep
blood sugar levels under control (Emebu and Anyika, 2011). The crude fiber content of
9.33% obtained by Yirankinyuki et al. (2015) were higher than 2.67 % in Indigofera
astragalina (Gafar et al., 2011) and lower (13 %) in Tribulus terrestris leaves and 29.00
% in Balsam apple leaves (Hassan and Umar, 2006).
The value was within the range of 0.70- 12.0 % for most leafy vegetables
except Balsam leaves (Gafar et al., 2011). The presence of high crude fiber in food
material is reported to decrease dry matter digestibility in animals. Fiber is useful for
maintaining bulk, motility, increase intestinal peristaltic movement and prevent colon
cancer (Omale et al., 2010). There is a variation in the value of crude fiber and it range
from 7.31% (E. communis) to 20% (H. aromatica) which is much higher than the
reported value (8.54%) in H. aromatica (Seal and Chaudhuri, 2015). Barua et al. (2015)
stated that there may be a variety of many reasons for such changes due to climate, soil
173
composition and season of collection as the samples were usually collected during winter
season when the fiber content was very high.
Carbohydrates are the principal source of energy. The carbohydrate
content was found highest in shade dried sample of lambs quarter (68.62%) as compared
to other vegetables (Table 12, Figure 10). While, the spinach vegetable was noted with
lower carbohydrate values as compared with nontraditional vegetables. Imran et al.
(2007) reported the closely related results of some wild edible leaves such as spinach,
sweet potato and triden which were 54.20, 75.00 and 82.80%, respectively. On the other
hand, the results were considerably higher than the reported values when compared to
some nontraditional edible plants (3%) of Pakistan (Khan et al., 2013) and commonly
consumed vegetables (29.40 - 32.80%) in Nigeria (Onwordi et al., 2009). Due to the
carbohydrate content, the vegetables can be a good food source of carbohydrate for
human consumption. Carbohydrate is a group of organic compounds that includes sugars,
starches, cellulose, and gums. It serves as a major energy source in the diet of humans
and animals. These compounds are produced in the photosynthetic plants and contain
only carbon, hydrogen and oxygen in the ratio of 1:2:1. Carbohydrates perform numerous
important functions in human and animal bodies. Lee and Lim (2006) isolated new
glycoprotein (150 KDa) from Solanum nigrum, which also contained carbohydrate
component (69.74%) and protein content (30.26%).
Audu et al. (2007) reported carbohydrate from leaves of Lophira
lanceolata. Hameed et al. (2008) found carbohydrates contents in R. hastatus, R. dentatus
and R. nepalensis. Folarin and Igbon (2010) noticed carbohydrate from Enterolobium
174
cyclocarpum seed. Aberoumand (2012) also revealed that Solanum indicum contained
40.67% carbohydrate. All these studies are in agreement with the present findings. The
high levels of carbohydrate in nontraditional vegetables indicate that they contribute
significantly to the energy content of the food materials (Sidibe and Williams, 2002;
Yirankinyuki et al., 2015). The most important function of carbohydrates is to fulfil the
body’s energy requirement (Igwe et al., 2015). High content of carbohydrates suggests
the rich source of energy supply and may be a veritable tool for the rural people as a
source of body nourishment (Antia et al., 2006).
The nontraditional vegetables also contain organic acids (e.g. oxalic acid,
citric acid, acetic acid, tartaric acid) in all the selected vegetables (Table 14-17, Figure
11-14) which have ability to prevent or kill microbes in vegetables and fruits (Bari et al.,
2003). Organic acids are primary metabolites known to exhibit antimicrobial, antioxidant,
and anti-tumorous effect and plays important role in plant metabolism as they are
involved in several fundamental pathways (Kathirvel et al., 2014). Organic acids are
mainly used in preparation of juices and beverages as food additives because they greatly
influence the aroma, taste, and color of the food (Kumari et al., 2017). Beside, this, the
identified organic acids also used in food processin and preservation owing to their
antimicrobial, antiviral, and high antioxidant properties (Sivasubramanian and Brindha,
2013).
175
It has been demonstrated that the edible vegetables are capable of
accumulating high levels of minerals from the soil (Cobb et al., 2000). The results of the
present study showed that (Table 19- 26, Figure 15- 22) the thermally dehydrated
samples retained the highest mineral content followed by shade dried, cooked, fresh and
boiled samples. The highest calcium, magnesium, sodium and potassium content were
found in thermally dehydrated samples of lambs quarter (568.8, 108.4, 1211.5 and 1081.4
mg 100g-1
). The copper and zinc were found highest in amarathus (3.026 and 7.240 mg
100g-1
) whereas the fe and manganese contents were maximum in gram leaves (4.810 and
1.950 mg 100g-1
). The lower values of mineral content of spinach vegetable were
recorded when comparing with nontraditional vegetables. Horo and Topno (2015)
reported that the nontraditional leafy vegetables are delicious, refreshing and rich in
minerals.
The copper content was recorded greater in thermally dehydrated sample
of amaranthus that is up to 3.026 mg 100 g-1
. The present results are also in line with
Gupta et al. (2005) who recorded the highest amount of copper content in some wild
vegetable Cocculus hirsutus, Boerhaavia diffusa, Centella asiatica and Delonix elata and
lowest in Amaranthus tricolor and Commelina benghalensis.
Iron content of the fresh samples of studied nontraditional wild vegetables
compared favorably to most of the results reported from other studies that the range of fe
content was recorded from 6.97 to 22.73 mg 100g-1
for some wild green leafy vegetables
in North-East India and from 21.30 to 33.40 mg 100g-1
for some commonly and wildly
grown and consumed leafy vegetables in Kano, Nigeria (Saikia and Deka, 2013).
176
Consumption of these nontraditional vegetables may help to overcome iron deficiency
anemia.
Zn as an integral part of many enzymes in human body plays catalytic,
structural and regulatory roles. It is essential for normal growth, mental ability, immune
system, reproduction and healthy function of the heart (Afolayan and Jimoh, 2009). The
zinc content of fresh Amaranthus (4.66 mg 100 g-1
) in present study compares favorably
to Dhekishak (2.29 mg 100 g-1
) as reported by Satter et al. (2016).
The highest Mn value was found in the dried leaves of gram leaves (1.950
mg 100g-1
). This element plays a significant role in the metabolism of fat, carbohydrate
and protein and boost the production of steroid sexual hormones (Saikia and Deka, 2013).
The result of mineral analysis reveals that the leaves of lambs quarter
contain high amount of calcium content (568.8 mg 100 g-1) in thermally dried sample.
The results are in agreement with the Gupta et al. (2005) who reported that the
Amaranthus tricolor, Cucurbita maxima, Boerhaavia diffusa and Digera arvensis had
high content of calcium content of 239, 302, 330 and 506 mg 100 g-1
, respectively.
Calcium has various functions in the body as it is present in extracellular fluid, blood and
bone in large proportions and also regulates normal functioning of cell permeability, milk
clotting, blood coagulation and cardiac muscles (Indrayan et al., 2005).
Magnesium is a mineral element important for circulatory diseases like
metabolism of calcium in bones and ischemic heart disease (Hassan and Umar, 2006).
177
The magnesium content was found highest in Lambs quarter (108.4 mg 100-1
) followed
by Amaranthus (101.3 mg 100-1
), gram leaves (77.45 mg 100-1
), horse radish tree flowers
(61.81 mg 100-1
) and spinach (50.16 mg 100-1
) treated with thermal dehydration. It has
also reported that Mg in some wild plants Echinops giganteus, Capsicum frutescens,
Piper guineense and Piper umbellatum of Cameroon was found 89, 254, 296 and 490 mg
100g-1
, respectively (Bouba et al., 2012). Magnesium plays major function in maintaining
the normal functioning of muscle and nerve, support healthy immune system and control
blood glucose levels (Saikia and Deka, 2013).
Noteworthy sodium concentration was recorded 491.6, 511.6, 499.6, 401.6
and 501.6 mg 100g-1
in fresh leaves of amaranthus, lambs quarter, gram leaves, horse
radish tree flowers and spinach are very much compared with the values observed by
Odhav et al. (2007) in the leaves of Oxygonum sinuatum (1460 mg 100g-1
) while C.
asiatica (16 mg 100g-1
) contained the lowest amount. Hence, the consumption of these
vegetables may control the high blood pressure. The potassium (828.54 mg 100 g-1
) in
fresh sample of Lambs quarter in the present study was higher than 14.55 mg 100 g-1
found in Indigofera astragelina leaves (Gafar et al., 2011) and also that of
Mucunasloanei. Similarly, Seal et al. (2017) also reported that the P. acinosa leaves had
highest potassium content (75.72 mg g-1
) and minimum in M. khasianus fruit (13.74 mg
g-1
). Potassium has diuretic nature and Na helps in transport of metabolites. The Na/K
ratio helps in preventing high blood pressure in human body (Saupi et al., 2009).
178
The recorded difference is may be due to variation in agronomic, climatic,
seasonal, and genetic background. Regular intake of these nontraditional vegetables may
help in inhibiting cardiovascular and hypertension diseases (He and MacGregor, 2008).
Sun drying is the gradual loss of water through evaporation and cannot
support leaching. It has to be noted that minerals are not volatile (Hailu and Addis, 2016).
The statistically significant ( < 0.05) reduction of iron and zinc concentration upon
cooking and peeling of the tuber may be because of the presence of minerals in the outer
non edible part of the tuber which was removed by peeling after boiling the tuber (Hailu
and Addis, 2016). The same reason may apply to the minerals which showed enormous
reduction in the boiled and peeled D. abyssinica. Reduction in zinc content was also
reported in peeled and boiled tubers of Dioscorea cayenensis (Akin-Idowu et al., 2009).
The presence of phytochemicals is an indication that the leaves could be
used for medicinal purposes (Offor et al., 2017). The medicinal relevancy of these leafy
vegetables is manifested in their usage by local people in the preparation of pot herb for
curing of various ailments (Olujobi, 2015). Table 28- 32 (Figure 23- 27) shows the
presence of phytochemicals (alkaloids, saponins, flavonoids, phenols and tanins) in
amaranthus, lambs quarter, gram leaves and horse radish tree flowers vegetables.
However, spinach vegetable was detected with only three phytochemicals namely,
flavonoids, phenols and tanins. This assertion is in consonance with the opinion of Musa
et al. (2000), who noted that extract from Acalypha species could be used as anti-biotics.
Saponin has been reported to suppress cholesterol build up in the body, while tannin has
been used in the treatment of common pathogenic strains in the body (Kubmarawa et al.,
179
2007). Though, phytate have been implicated with some nutritional diseases such as bio-
availability of mineral elements, and inhibitions of some metabolic activities, the values
obtained in this study were below the established toxic level of 6% (Sobowale et al.,
2011).
Phytochemicals are natural bioactive compounds found in plants that work
in close association with nutrients and dietary fiber for disease protection (Oteng-Gang
and Mbachu, 1990). Tannins are regarded as agents for toning of vital organs such as
kidney and liver. The phytochemical composition determines the medicinal values of
these edible nontraditional vegetables and also could serve as a starting material for the
synthesis of new drugs in pharmaceutical industries (Okerulu and Onyema, 2015). Plant
tannins have a variety of health benefits and intake of tannin containing diet could help in
good health maintenance. Tannins are a unique phytochemical, particularly in terms of
their vast potential health benefit. Analysis of tannins composition in different plant
foods including ethnic plant foods would encourage their consumption for maintenance
of good health (Tuli et al., 2017).
Each of these phytochemicals is known for various protective and
therapeutic effects (Asaolu et al., 2009). Tannins impose an astringent taste in foods
thereby affecting palatability (Ogbede et al., 2015). However, tannin compounds have
been reported to possess antibacterial (Akiyama et al., 2001), antiviral and antiparasitic
effects (Kolodziej et al., 2005). The phenolic content of these nontraditional vegetables
was significantly higher in comparison to Brassica juncea, the commercialized vegetable
180
(Ng et al., 2012). The results are also relatively higher than the commonly consumed
food plants from India (0.0-1.2 mg GAE/g raw foodstuff) as reported by Saxena et al.
(2007). Phenolics are nonnutritive secondary metabolites found in plants that promote
significant health benefit and prevent various diseases. Study by Stagos et al. (2012) and
Delgado et al. (2009) stated that phenolic compunds can prevent cardiac and
neurodegerative diseases.
The total flavinoid content of the studied plants is comparable to some of
the medicinal plants (1.6-13.12 mg RE/g DW) and vegetables (0.9- 4.9 mg RE/g DW)
reported in the previous studies (Djeridane et al., 2006). Oxalates are known to combine
with and isolate some useful metallic elements thus causing them to be deposited in solid
forms. This, in effect, makes them unavailable for adsorption in human system (Alamu et
al., 2013). The oxalate contents were 1.31± 0.020 and 0.36± 0.02%, while the tannin
values were 0.04± 0.00 and 0.03± 0.00% respectively. The saponin contents the other
hand were 2.53± 0.02 and 1.13± 0.00% (Ndamitso et al., 2015). Alkaloids have immense
physiological activities in the living systems hence they are widely used in medicine
(Olaofe and Sanni, 2007).
The alkaloid contents of these samples were 0.65±0.02 and 0.68±0.02%
for the leaves and stems respectively (Olaofe and Sanni, 2007). The respective flavonoid
contents of the samples were 0.52± 0.03 and 0.34± 0.02% for the leaves and stems
respectively (Ndamitso et al., 2015). However, anti-nutritional factors encountered in
fruits, vegetables and grains which do not have nutritional values but they do affect
181
various body processes and reduce the risk of many diseases such as cancer, heart
diseases, stroke, high blood pressure, cataracts and urinary tract infection (Okwu and
Ndu, 2006). Appropriate processing methods are known to reduce the antinutritional
activity of these factors (Hailu and Addis, 2016). According to Yadav and Sehgal (2003),
the oxalate content was equal to 3.05 mg 100g-1
, value lower than that is reported (14.9 g
100g-1
) in common green leafy vegetable spinach (Spinacia oleracia).
The value obtained for vitamins from the amaranthus, lambs quarter, gram
leaves and horse radish tree flowers and spinach vegetables in fresh, thermally
dehydrated, curry, shade dried and boiled samples (Table 34- 38, Figure 28- 32) revealed
that the nontraditional and commercial vegetables have almost similar pattern of vitamin
content and are rich in vitamins and the values shows a close agreement with those
obtained by Adeniyi et al. (2011). In some selected leafy vegetables, vitamins B1, B2 and
B3, have been reported to be highly essential for micronutrient metabolism whereas
vitamin C is used for protein metabolism and collagen synthesis (Vunchi et al., 2011).
Vitamin A and beta-carotene are essential for good vision (Adeyeye, 2014). Results
available reviewed and current study demonstrated that the wild species contained
valuable amount of vitamins such as riboflavin and ascorbic acid (Ng et al., 2012). The
riboflavin content was the highest in Limnophila aromaticoides (13.7 μg g-1
FW)
followed by Crassocephalum crepidioides (12.4 μg g-1
FW) and were of the same
magnitude as that generally found in dairy product. Therefore, daily consumption of these
vegetables might help to alleviate riboflavin deficiency, which gives negative impact on
the metabolism of other nutrients, especially B-group vitamins, through flavin coenzyme
182
activity. The sufficient intake of riboflavin on the other hand had proven to have
protective effect against proximal colon cancer (De-Vogel et al., 2008).
The amount of thiamine in Limnophila aromaticoides (16.6 μg g-1
FW),
Ceratopetris thalictroides (9.0 μg g-1
FW) and Etlingera elatoir (3.24 μg g-1
FW) were
high as compared to the uncommon vegetables studied by Raghuvanshi et al. (2001).
Nevertheless, plants or vegetables usually contain great amount of heat-stable anti-
thiamine compounds such as tannic acid and thiaminase I, which usually affect the
bioavailability of thiamine in plants (Lonsdale, 2006). According to the findings of Lui et
al. (2008), high concentration of ascorbic acid in plant samples might be associated with
attractive free radical scavenging capacity and health benefit like anti-carcinogenic and
anti-atherogenic.
The β-carotene content of the indigenous vegetables in this study were 2-
5 times lower than that of other vegetables, such as carrots (Daucus carota; 18,300 g
100g-1
), sweet potato (Ipomea batatas; 9500 g 100g-1
), and pumpkin (Cucurbita maxima;
6900 g 100g-1
). All of these vegetable varieties are excellent sources of β-carotene
(Krinsky and Johnson, 2005). The vitamin acts as an antioxidant to prevent free radicals
from damaging tissues and to inhibit LDL oxidation that can lead to atherosclerosis
(Osganian et al., 2003). Because humans are incapable of synthesizing vitamin C due to
the absence of L. gluconolactone oxidase, this vitamin must be obtained from the diet
(Kongkachuichai et al., 2015) with cashew apple pulp (ripe) and Spanish joint fir having
the highest quantities and the lowest content in turmeric. Puwastein et al. (1999) reported
183
that vegetables including horse radish tree (Moringa oleifera; 239 mg 100g-1
), green chili
pepper (Capsicum annuum; 175 mg 100g-1
), coriander (Coriandrum sativum; 127 mg
100g-1
), and kale (Brassica oleracea; 117 mg 100g-1
) had equivalent or higher amounts of
vitamin C.
The total solids were highest in thermally dehydrated samples of all the
vegetables than other treatments (Table 40, Figure 33). The total soluble solids in Table
41 (Figure 34) were observed highest in thermally dried sample of gram leaves (2.680
°Brix).
The results of the present study revealed that the nontraditional vegetables
have the potential to provide essential nutrients needed in human diet for maintaining the
normal body function. Table 42 (Figure 35) shows that amaranthus had maximum energy
value (271.6 Kcal 100g-1
) than spinach (269.8 Kcal 100g-1
), lambs quarter (268.7 Kcal
100g-1
), gram leaves (269.0 Kcal 100g-1
) and horse radish tree flowers (249.0 Kcal 100g-
1). Hussain et al. (2011), Mohammed and Sharif (2011), Khan et al. (2013) reported that
the nontraditional vegetables were a good nutritional source and in some cases, they were
better than those of some organized green cultivated vegetables. Thus, they are capable of
providing energy to the consumer and sufficient to fulfill the RDA by FAO/WHO (Satter
et al., 2016). The caloric values recorded in this study ranged between 246.39 Kcal to
313.94 Kcal with U. urens having the lowest.
184
Nonetheless, these three vegetable species can be considered a good
source of energy for both human and livestock whosoever has access to eat. These values
compared favorably with 285.02 Kcal and 260.93 Kcal reported for Argemone
subfusiformis and U. urens, respectively (Jimoh et al., 2010). Leptadenia hastata leaves
provided 286.32 Kcal of energy on dry weight basis which is within the range of 248.8-
307.1 Kcal 100g-1
reported in some Nigerian leafy vegetables (Isong et al., 1999). It
therefore, suggests that Leptadenia hastata can serve as a good source of energy
supplement for the body (Yirankinyuki et al., 2015). Chionyedua et al. (2009) reported
the energy values of C. olitorius (177.55 Kcal 100g-1
), A. cruentus (176.67 Kcal 100g-1
)
and C. argenta (174.93 Kcal 100g-1
). The energy value of plant tubers was estimated
within the range of 272.4- 266.04 Kcal 100g-1
(Deshmukh and Rathod, 2013). Senna
occidentalis and Wahlenbergia undulata yielded the highest energy levels of 84 and 75
Kcal 100g-1
, respectively. These results also indicate that 50% of the vegetables have
significant energy values ranging from 50 to 70 Kcal 100g-1
(Odhav et al., 2007).
The pH content was found highest in boiled, curry and fresh samples of
lambs quarter (7.446, 7.373 and 7.260, respectively) as compared to other vegetables
(Table 43, Figure 36). Ndamitso et al. (2015) studied the pH value of leaves and stems of
Ipomoea Aquatic (water spinach) and noted that the respective pH values of 5.83± 0.015
and 5.80± 0.020 for the leaves and stems were relatively the same indicating that both
parts of the plant were only slightly acidic in nature.
185
Chlorophyll is a natural dye derived from green plants and it absorbs
energy from the sun that is used to synthesize carbohydrates from CO2 via photosynthesis
(Raven et al., 2005). The higher plants in their chloroplast contain two types of
chlorophyll i.e. chlorophyll a (blue-green) and chlorophyll b (yellow-green), which differ
in the substituent of a pyrrole ring II. In addition, it’s photosynthetic role it has other
applications and is used as a natural pigment in food and cosmetics (Humphery, 2004).
The results of the a, b and total chorophyll (Table 47, Figure 39) revealed that lambs
quarter had the highest total chlorophyll content (3.199 mg g-1
) followed by spinach
(1.888 mg g-1
), amaranthus (1.850 mg g-1
), gram leaves (1.504 mg g-1
) and horse radish
tree flowers (0.048 mg g-1
).
The leaf chlorophyll content provides important information about growth,
production, physiological status of the plant and ensure the quality of of crop and yield
(Menesatti et al., 2010; Riccardi et al., 2014; Zhang et al., 2016). This practice has an
important significance for the modern precision agriculture (Zhang et al., 2016). The
content of pigments in plants is important, not only for coloration and physiological
function, but also because of their acknowledged roles in health (Niizu and Rodriguez-
Amaya 2005; Liu et al. 2007,). Highest total chlorophyll was found in Rumex nepalensis
(1.58 mg g-1
), followed by Justicia adhatoda (1.53 mg g-1
) while the lowest total
chlorophyll content was recorded in Basella rubra (0.57 mg g-1
). The total chlorophyll
was also found to be high in Passiflora edulis (1.39 mg g-1
), Spilanthes acemella (1.37
mg g-1
), Piper longum (1.21 mg g-1
) and Amaranthus viridis (1.20 mg g-1
) (Buragohain et
al., 2013).
186
Sensory evaluation of cooked and uncooked vegetables
The desireability of any food product is depend on its quality which can be
determined by objective and sensory methodologies. The psychometric, sensory,
organoleptic and subjective tests are taken by human organs to check the quality of food
(Srilakshmi, 1996). Sensory analysis of food relies upon evaluation through the use of
our senses (odor, taste, tactile, temperature, etc.). Only by applying exact scientific
testing methods can lead to reproducible results. Scientific methods of sensory analysis of
foods are becoming increasingly important in assessing the acceptability of food products
(Jellinek, 1985). According to Vaid (2008) that sensory quality is composed of various
wisdoms of sensitivity during selecting and eating a food. Physical appearance, mouth
feel and flavor decide the recognition of food. By using senses (odour, taste, tactile,
temperature, etc.) sensory analysis of a food could be carried out. However, statistical
analysis and reproducible results could be obtained only by applying exact scientific
testing methods.
The results of the sensory evaluation of the uncooked and cooked samples
in present study revealed that all samples had good taste (Table 48 and 49, Figure 40-
49). In uncooked samples horse radish tree flowers obtained highest scores in appearance,
color, odor, texture, taste, overall acceptability and purchase i.e. 4.90, 4.70, 4.00, 3.90,
3.50, 3.80 and 3.80, respectively. While in traditionally cooked samples cooked lambs
quarter and gram leaves retained original color and thus obtained the highest scores in
appearance and taste i.e. 3.70, 3.90 and 3.70, 3.50, respectively. The lambs quarter
187
vegetable retained pleasant odor with the score of 3.50, as compared with horse radish
tree flowers, gram leaves, amaranthus and spinach (3.30, 3.20, 3.10 and 3.10,
respectively). Acceptability study by hedonic scoring showed that nontraditional
vegetables (horse radish tree flowers, lambs quarter, gram leaves and amaranthus) made
by traditional cooking were most acceptable as compared with commercial vegetable
(spinach).
The findings of the present study are in line with the study of
Umuhozariho et al. (2013), who carried out sensory evaluation of cooked cassava
species. According to them cassava species do not considerably effect aroma, colour and
taste. Similar results were obtained by Tarkergari et al. (2013) who found significant
differences in a few of the recipes fortified with purslane that of control. Ward et al.
(2009) based on selective chemical and physical properties studied patties containing 5
and 10% purslane for sensory evaluation for colour, juiciness tenderness texture and
flavour and rated 5% incorporation to be significantly better than 10% incorporation. It
has been experienced that only those foods are acceptable to the human palate, which are
cooked properly and the criterion of the desirability of any food product depends on its
ultimate quality. The quality of a food could be assessed by sensory and scientific
methods.
188
CHAPTER-VI
SUMMARY
The present study was conducted to observe the impact of traditional
processing methods on nutritional composition and bioactive constituents of non-
traditional (lambs quarter, amaranthus, gram leaves and horse radish tree flowers) and
commercial (spinach) vegetables of Sindh, Pakistan. The nutritional values of
nontraditional vegetables were also compared with the standard vegetable spinach. The
findings of the study are summarized as under:
Nontraditional vegetables play a vital role in the diet of the people
throughout the world. The increasing populations of the world coupled with urbanization
have increased food demands and have not only increased overwhelmed pressure on
available land resources for more productivity but have also accentuated the post-harvest
losses. This has also created a demand for better and increased yields of vegetables, their
appropriate storage and preservation. But due to lack of adequate resource availability
ultimately leads to malnutrition caused by insufficient nutrients which are needed to
maintain healthy body/ functional ability. There is great potential for a number of
currently nontraditional vegetables to play a major role in a more diversified and
sustainable food production system. It has been observed from the survey that Gram
leaves was the most popular non-traditional vegetable eaten frequent or occasionally by
82% respondents only 18% respondents never tasted or do not know this vegetable. Next
popular vegetables which majority of respondent never tasted or did not know included
amaranthus and lambs quarter. About 62% respondents never tasted or do not know
189
Horse radish tree flowers as vegetable while 38% respondents answered they eat frequent
or occasionally.
The nontraditional namely, lambs quarter, horse radish tree flowers, gram
leaves, amaranthus and commercial (spinach) vegetables were analyzed for their
nutritive, mineral, vitamin, phytochemical and chlorophyll composition. The results from
nutritional analysis showed that all the nontraditional vegetables used in this study had
low moisture content as compared with spinach. It was observed that moisture content
was high in boiled samples of horse radish tree flowers, lambs quarter, gram leaves and
amaranthus (87.26, 85.46, 84.13 and 83.05%). However, the moisture content in
cultivated spinach vegetable was recorded highest in boiled (92.66%) and fresh (88.76%)
samples which means that spinach is highly perishable which cannot be stored for long
time duration.
The ash content (total minerals) in respective vegetables ranged from
1.227 – 10.56% for amaranthus, 1.187 – 9.507% for lambs quarter, 1.213 – 10.43% for
gram leaves and 0.487 – 16.15% for horse radish tree flowers. However, the ash content
for spinach vegetable was noted 0.507 to 8.680%. The results of the present study
showed that nontraditional vegetables are rich in total mineral content as compared with
commercial vegetable (spinach). The protein content in Table 9 (Figure 7) was observed
greater in thermally dehydrated gram leaves (7.56%) as compared to other nontraditional
vegetables and in spinach low protein content was observed (1.04% in boiled sample).
The crude fat and fatty acid content was recorded highest in curry samples whereas crude
190
fiber was found maximum in thermally dehydrated samples of the selected vegetables.
The carbohydrate content was found highest in shade dried sample of lambs quarter
(68.62%) as compared to other vegetables. The results revealed that nontraditional
vegetables are rich sources of energy as compared with spinach.
The thermally dehydrated samples retained the highest mineral and
organic acid content followed by shade dried, cooked, fresh and boiled samples. The
highest calcium, magnesium, sodium and potassium content were found in thermally
dehydrated samples of lambs quarter (568.8, 108.4, 1211.5 and 1081.4 mg 100g-1
). The
copper and zinc were found highest in amarathus (3.026 and 7.240 mg 100g-1
) whereas
the fe and manganese contents were maximum in gram leaves (4.810 and 1.950 mg 100g-
1). The lower values of mineral content of spinach vegetable were recorded when
comparing with nontraditional vegetables.
The presence of phytochemicals (alkaloids, saponins, flavonoids, phenols
and tanins) in amaranthus, lambs quarter, gram leaves and horse radish tree flowers
vegetables. However, spinach vegetable was detected with only three phytochemicals
namely, flavonoids, phenols and tanins. The presence of phytochemicals is an indication
that the leaves could be used for medicinal purposes. The value obtained for vitamins
from the amaranthus, lambs quarter, gram leaves and horse radish tree flowers and
spinach vegetables in fresh, thermally dehydrated, curry, shade dried and boiled samples
revealed that the nontraditional and commercial vegetables have almost similar pattern of
vitamin content and are rich in vitamins.
191
The total solids were highest in thermally dehydrated samples of all the
vegetables than other treatments. The total soluble solids in were observed highest in
thermally dried sample of gram leaves (2.680 °Brix). The results of the present study
revealed that the nontraditional vegetables have the potential to provide essential
nutrients needed in human diet for maintaining the normal body function. The
amaranthus had maximum energy value (271.6 Kcal 100g-1
) than spinach (269.8 Kcal
100g-1
), lambs quarter (268.7 Kcal 100g-1
), gram leaves (269.0 Kcal 100g-1
) and horse
radish tree flowers (249.0 Kcal 100g-1
). The pH content was found highest in boiled,
curry and fresh samples of lambs quarter (7.446, 7.373 and 7.260, respectively) as
compared to other vegetables.
Ideally, the prevalence of macro and micronutrient related disorders can
be addressed by fortification and supplementation, but this has to be subsidized because it
can be expensive and hence financially inaccessible to the rural population who form the
majority of the macro and micronutrient deficiency victims. Taking into account the
amount of available nutrients and bioactive compounds in the selected nontraditional and
commercial vegetables it was observed that nontraditional vegetables are also valuable
and important contributor to the diets of the people as commercial vegetables and also
these nontraditional vegetables grow without any agricultural input are available at lower
prices affordable to rural masses. Therefore, among alternatives available to meet the
food demands nontraditional vegetables are regarded as cheap source of food for the
marginal communities in Sindh, Pakistan
192
The results of the sensory evaluation of the uncooked and cooked samples
in present study revealed that all samples had good taste. In uncooked samples horse
radish tree flowers obtained highest scores in appearance, color, odor, texture, taste,
overall acceptability and purchase i.e. 4.90, 4.70, 4.00, 3.90, 3.50, 3.80 and 3.80. While
in traditionally cooked samples cooked lambs quarter and gram leaves retained original
color and thus obtained the highest scores in appearance and taste i.e. 3.70, 3.90 and 3.70,
3.50, respectively. Acceptability study by hedonic scoring showed that nontraditional
vegetables (horse radish tree flowers, lambs quarter, and gram leaves and amaranthus)
made by traditional cooking were most acceptable as compared with commercial
vegetable (spinach). Therefore, these nontraditional vegetables can be consumed in
cooked form like other commercial crops. To alleviate the situation, efforts need to be
focused on exploring possibility of the under exploited and lesser known vegetables as a
source of nutrients as food items and supplements.
To epitomize, from the present results and detailed quoted literature it was
observed that assuring food supply to the rural areas, particularly in developing countries
is one of the biggest challenges. Use of nontraditional vegetables is important but ignored
facet for food supply in such areas. The present study revealed that nontraditional
vegetables form good quality food to rural communities thus play important role in
nutritional security to rural areas. However, they need proper focus in policies and
conservation. Perhaps a proper documentation of traditional knowledge related to the
utilization of such resource is an urgent need in Pakistan. Subsequently it is
recommended that, since these nontraditional vegetable species provide food security,
193
thus can play significant role in uplifting socio-economic status of rural people as well as
save the natural habitats. It could be safely said that promoting nontraditional vegetables
would certainly strengthen multifunctional agricultural policies for securing food and
livelihood security and environmental sustainability in urban and peri-urban areas of
Pakistan. Increasing the production of nontraditional vegetables and informing people
how to cook vegetables to gain maximum nutritional value will help ensure low cost
nutrients reach vulnerable populations and enhance food and nutritional security. At the
same time it would also facilitate in sustaining rural landscapes, biodiversity, cultural
heritage and increase life expectancy in Sindh, Pakistan.
194
CHAPTER-VII
CONCLUSIONS AND RECOMMENDATIONS
Conclusions
In conclusion, it was observed that the nontraditional vegetables naturally
grown in district Mirpurkhas of Sindh Pakistan are rich with their nutritive values when
comparing to standard commercial vegetable spinach. These nontraditional vegetables
have higher concentrations of the carbohydrate, protein, fiber, minerals, vitamins,
phytochemicals, greater energy values and lower amount of fat and fatty acids. The
processing treatments showed significant effects on the nutritional values of the selected
vegetables out of which boiling and cooking showed the adverse effects. In sensory
evaluation, the panelists preferred the nontraditional vegetables to commercial vegetable
(spinach).
Moreover, the nutrient and bioactive compounds obtained from selected
nontraditional vegetables studied have high potential to contribute to the nutritional and
health status of local as well as urban communities in Sindh, Pakistan. Their use in the
communities should therefore be promoted. These nontraditional vegetables can be
consumed together with starchy staples as part of a balanced diet and help to alleviate
some nutritional deficiencies.
By studying the bioavailability of the nutrient and minerals content of
nontraditional vegetables together with the optimization of their properties and nutritional
195
values in the daily food of the population will ultimately lead to their higher demand,
wider cultivation and increased supply. The projection of population in Pakistan as
regards life expectancy and food security are quite depressing and challenging aspects of
the moment. Obtaining information and promoting knowledge about high functional
value of selected nutrient rich nontraditional vegetables could potentially address some of
these challenges. Increasing the production of nontraditional vegetables and making the
people aware, how to prepare vegetables to gain maximum nutritional value will help
ensure low cost nutrients availability to reach vulnerable populations to enhance food and
nutritional security as well as life expectancy.
Recommendations
Since the nontraditional vegetables investigated in this study contained
considerable amount of important nutrients it is suggested that:
1) They should be taken as food or added to food as condiments to supplement variety
of nutrients in human diet especially among the rural dwellers with low income.
2) It is also recommended that Government and corporate bodies should embark on
plantation establishment of these species for sustainable production.
3) The study can be extended on more recipes to study the effect of different cooking
methods.
4) In order to expand utilization and conservation of the two indigenous vegetables,
farmers and people at large should be informed about nutritional importance and
health benefits of these nontraditional vegetables.
196
5) The Ministry of Agriculture and partners in the agriculture sector should explore
domestication of these vegetables through agronomic studies.
6) Further research is needed to determine the anti-microbial activities of nontraditional
vegetables to establish medicinal properties of the plant in the treatment of diarrhea/
dysentery and fresh wounds.
7) The optimum conditions and technologies may be established for the retention of
compounds with nutritional value and non-nutrient health promoting benefits in the
nontraditional vegetables.
8) The research and extension services should focus on these nontraditional vegetables
in order to harness their potentials for the enhancement of the livelihoods of farmers
that are dependent on it.
9) Farmers should also organize themselves as niche group for the marketing of
nontraditional vegetables such that they may have better returns.
197
LITERATURE CITED
Abara, A. E. (2003). Tannin content of Dioscorea bulbufera. J. Chem. Soc. Nigeria., 28:
55-56.
Abbasi, A. M., M. A. Khan, M. Ahmad, R. Qureshi, M. Arshad, S. Jahan, M. Zafar and
S. Sultana (2010). Ethnobotanical study of wound healing herbs among the
tribal communities in northern Himalaya ranges district Abbottabad, Pakistan.
Pak. J. Bot., 42(6):3747-3753.
Abbasi, A. M., M. A. Khan, N. Khan and M. H. Shah (2013). Ethnobotanical survey of
medicinally important wild edible fruits species used by tribal communities of
lesser Himalayas-Pakistan. J. Ethnopharmacol., 148(2): 528-536.
Aberoumand, A. (2012). Studies on nutritional value of some wild edible plants from Iran
and India. Pakistan J. of Nut., 8: 26-31.
Abuye, C., K. Urga, H. Knapp, D. Selmar, A. M. Omwega, J. K. Imungi and P. A.
Winterhalter (2003). Compositional study of Moringa stenopetala leaves. East
Afric. Med. J., 80(5): 51-56.
Achir, N., V. A. Randrianatoandro, P. Bohuon, A. Laffargue and S. Avallone (2010).
Kinetic study of beta-carotene and lutein degradation in oils during heat
treatment. European J. Lipid Sci. Technol., 112: 349-361.
Adebooye, O. C. and J. T. Opabode (2004). Status of conservation of the indigenous leaf
vegetables and fruits of Africa. Afric. J. Biotechnol., 3(12): 700-705.
Adenipekun, C.O. and O.J. Oyetunji (2010). Nutritional values of some tropical
vegetables. J. Appl. Biosci., 35: 2294-2300.
Adeniyi, S. A., J. E. Ehiagnonare and S. C. O. Nwamgwu (2011). Nutritional evaluation
of some staple leafy vegetables in southern Nigeria. Inter. J. of Agric. Food
Sci., 2(2): 37-43.
Adeyeye, E. I. (2014). “You are what you eat” Inaugural lecture delivered at the dept. of
chemistry, Ekiti State University, Ado- Ekiti. Pp: 135
Adnan, M., J. Hussain, M. T. Shah, Z. K. Shinwari, F. Ullah, A. Bahader, N. Khan, A.L.
Khan and T. Watanabe (2010). Proximate and nutrient composition of
medicinal plants of humid and sub-humid regions in North-West Pakistan. J.
Med. Plant Res., 4: 339-345.
Afolayan, A. J. and F. O. Jimoh (2009). Nutritional quality of some wild leafy vegetables
in South Africa. Int. J. Food Sci. Nutr., 60(5): 424- 31.
Agarwal, A., N. Raj and N. Chaturvedi. (2017). A comparative study on proximate and
antioxidant activity of Brassica oleracea (Kale) and Spinacea oleracea
(Spinach) leaves. Int. J. Adv. Res. Biol. Sci., 4(4): 22- 29.
198
Agbaire, P. O. (2012). Levels of anti-nutritional factors in some common leafy edible
vegetables of southern Nigeria. Afric. J. Food Sci. Technol., 3(4): 99-101.
Agea, J. G., J. Obua, J. R. S. Kaboggoza and D. Waiswa (2007). Diversity of indigenous
fruit trees in the traditional cotton-millet farming system: the case of Adwari
subcounty, Lira District, Uganda. Afric. J. Ecol., 45: 39-43.
Aguilera, J. M. (2003). Drying and dried products under the microscope. Food Sci.
Technol. Int., 9(3): 137-143.
Ahmad, S. S., S. Erum, S. M. Khan, M. Nawaz and A. Wahid (2014b). Exploring the
medicinal plants wealth: a traditional medico-botanical knowledge of local
communities in Changamanga forest, Pakistan. Middle-East J. Sci. Res.,
20(12): 1772-1779.
Ahmad, S. S., S. Z. Husain (2008). Ethnomedicinal survey of plants from salt range of
Pakistan. Pak. J. Bot., 40: 1005-1011.
Ahmed, J. (2011). Drying of vegetables: principles and dryer design. In: Sinha, N. K., Y.
H. Hui, E. O. Evranuz, M. Siddiq and J. Ahmed (Eds.), Handbook of
Vegetables and vegetable processing. Wiley-Blackwell publishing, pp: 279-
298.
Akin-Idowu P. E., R. Asiedu, B. Maziya-Dixon, A. Odunola and A. Uwaifo (2009).
Effects of two processing methods on somenutrients and anti-nutritional
factors in yellow yam (Dioscorea cayenensis). Afric. J. Food Sci., 3(1): 22-25.
Akinyeye, R.O., A. Oluwadunsin and A. Omoyeni (2010). Proximate, mineral, anti-
nutrients and phytochemical screening and amino acid composition of the
leaves of Pterocarpus mildbraedi Harms. Electron. J. Environ. Agric. Food
Chem., 9: 1322-1333.
Akinyeye, R.O., A. Oluwadunsin and A. Omoyeni (2011). Proximate, mineral, anti-
nutrients and phytochemical screening and amino acid composition of the
leaves of Pterocarpus mildbraedi Harms. Electron. J. Environ. Agric. Food
Chem., 10(1): 1848-1857.
Akiyama, H., K. Fujii, O. Yamasaki, T. Oono and K. Iwatsuki (2001). Antibacterial
action of several tannins against Staphylococcus aureus. J. Antimicrob.
Chemo., 48(4): 487-491.
Akpana, A. M., M. J. Edward, P. Henry and A. Joseph. (2017). Mineral and vitamin
composition of some lesser known leafy vegetables consumed in Northern
Senatorial District of Cross River State, Nigeria. Americ. J. Food Nutr., 5(2):
51- 57.
Akpanyung, E.O. (2005). Proximate and mineral composition of bouillon cubes produced
in Nigeria. Pak. J. Nutr., 4: 327-329.
199
Alam, A. M., A. S. Juraimi, M. Y. Rafii, A. A. Hamid, M. KamalUddin, M .Z. Alam and
M. A. Latif (2014). Genetic improvement of purslane (Portulaca oleracea L.)
and its future prospects. Mol. Biol. Rep., 41: 7395-7411.
Alamu, O. T., A. O. Amao, C. I. Nwokedi, O. A. Oke and I. O. Lawa (2013). Diversity
and nutritional status of edible insects in Nigeria: A review. Int. J. Biodiver.
Conserv., 5(4): 215-222.
Al-Bayati, F.A. and K. D. Sulaiman (2008). In vitro antimicrobial activity of Salvadora
persica L. extracts against some isolated oral pathogens in Iraq. Turk. J. Bio.,
32: 57-62.
Alessandra, G. and H. C. Robert (2005). The crucial role of metal ions in neuro
degeneration; the basis for promising therapeutic strategy. Brit. J. Pharmacol.,
146: 1041-1059.
Al-Faris, N. A. (2017). Nutritional evaluation of selected traditional foods commonly
consumed in Saudi Arabia. J. Food Nutr. Res., 5(3): 168- 175.
Allen, S. E. (1974). Chemical analysis of ecological materials. Blackwell Sci. Pub.
Oxford, London.
Antia, B. S., E. J. Akpan, P. A. Okon and I. U. Umoren (2006). Nutritive and anti-
nutritive evaluation of sweet potatoes (Ipomoea batatas) leaves. Pak. J. Nutr.,
5(2): 166-168.
AOAC. (2000). Official method of analysis of the association of the analytical chemists.
Inc. Virginia. USA.
AOAC., (1990). Official methods of analysis, Washington DC association of official
analytical chemists 14th Edition: 140- 147.
Aphane, J., M. L. Chadha and M. O. Oluoch (2003). Increasing consumption of
micronutrient-rich foods through production and promotion of indigenous
foods. In FAO-AVRDC international workshop proceedings 5-8 May 2002,
Arusha, Tanzania. AVRDC – The world vegetable center, Taiwan, AVRDC.
Argyropoulos, D., A. Heindl and J. Muller (2011). Assessment of convection, hot-air
combined with microwave-vacuum and freeze-drying methods for mushrooms
with regard to product quality. Int. J. Food Sci. Technol., 46 (2): 333-342.
Arimond, M., D. Wiesmann, E. Becquey, A. Carriquiry, M. C. Daniels, M. Deitchler, N.
Fanou-Fogny, M. L. Joseph, G. Kennedy, Y. Martin- Prevel and L. E.
Torheim (2010). Simple food group diversity indicators predict micronutrient
adequacy of Women’s diets in 5 diverse, resource-poor settings. J. Nutri.,
140(11): 2059-2069.
Arnon, D. L. (1949). A copper enzyme is isolated chloroplast polyphenol oxidase in Β.
vulgaris. Plant Physiol., 24: 1-15.
Arya, S. S., V. Natesan, D. B. Parihar and P. K. Vijayaraghvan (1979). Stability of β -
carotene in isolated systems. J. Food Tech., 14: 571-578.
200
Asaolu, M.F., O. A. Oyeyemi and J. O. Olanlokun (2009). Chemical compositions,
phyto-chemical constitutents and in vitro biological activity of various
extracts of cymbopognon citratus. Pak. J. Nutri., 8: 1920-1922.
Asibey-Berko, E. and F. A. K. Taiye (1999). Proximate analysis of some underutilized
Ghanain Vegetables. Ghana J. of Sci., 39: 91-92.
Asif, M. and A. Kamran (2013). J. M. Lenne and D. Wood (eds.): Agrobiodiversity
management for food security: A Critic. Rev. Food Sec., 5: 139-140.
Atabo, A. P., A. P. Ilecholubo and L. R. Abisoye. (2017). Assessment of proximate,
mineral and anti-nutritional compositions of Myrianthus arboreus leaves. Int.
J. Bioorg. Chem., 2(3): 125- 129.
Attaa, A., M. A. Sheikh, M. Shahid and T. Khaliq. (2016). Antioxidant and antiglycation
potential of polyphenol extracts of selected vegetables from Pakistan. Oxid.
Com., 39(3-I): 2249– 2259.
Attaa, A., G. Mustafa, M. A. Sheikh, M. Shahid and H. Xiao. (2017). The biochemical
significances of the proximate, mineral and phytochemical composition of
selected vegetables from Pakistan. Matrix Sci. Pharm., 1 (1): 06- 09.
Audu, S.A., I. Mohammed and H. A. Kaita (2007). Phytochemical screening of the leaves
of Lophira lanceolate (Ochanaceae). Life Sci. J., 4: 75-79.
Ayoola, P.B., A. Adeyeye and O. O. Onawumi (2010). Trace elements and major
minerals evaluation of Spondiasmombin, Vernonia amygdalina and
Momordica charantia leaves. Pak. J. Nutri., 9: 755-758.
Ayuba, V.O., T. O. Ojobe and S. A. Ayuba (2011). Phytochemical and proximate
composition of Datura innoxia leaves, seed, stems pod and roots. J. Med.
Plant. Res., 5: 2952-2955.
Bahadur, A. (2012). Ethnomedicinal study of Merbazghaz Jahangir Abad, Mardan,
Khyber Pukhtoon Khwa, Pakistan. Int. J. Pharmacol. Res. Dev., 4(1): 129-
131.
Baloch, A. K., K. A. Buckle and R. A. Edwards (1997). Effect of processing variables on
the quality of dehydrated carrot: leaching losses and carotenoid content. J.
Food Tech., 12: 285-293.
Bari, M. L., Y. Sabina, S. Isobe, T. Uemura and K. Isshiki (2003). Effectiveness of
electrolyzed acidic water in killing Escherichia coli O157:H7, Salmonella
enteridis and Listeria monocytogenes on the surfaces of tomatoes. J. Food
Prot., 66: 542-548.
Barros, L., S. Oliveira, A. M. Carvalho and I. C. F. R. Ferreira (2010). In vitro
antioxidant properties and characterization in nutrients and phytochemicals of
six medicinal plants from the Portuguese folk medicine. Indust. Crops Prod.,
32: 572-579.
201
Bartlett, J. E., J. W. Kotrlik and C. C. Higgins (2001). Organizational research:
determining appropriate sample size in survey research. Inform. Technol.
Learn. Perf. J. 19(1): 43-50.
Barua C. C., M. Bora, B. N. Saikia, M. Hazarika, J. Misri and I. Chandrabarua (2015).
Nutritional evaluation of few selected medicinal plants of north eastern
region. Int. J. Pharm. Biosci., 6(3): 538-546.
Barucha, Z. and J. Pretty (2010). The roles of wild foods in agricultural systems. Phil.
Trans. R. Soc. B., 365: 2913-2926.
Bassama, J., P. Brat, R. Boulanger, Z. Gunata and P. Bohuon (2012). Modeling deep-fat
frying for control of acrylamide reaction in plantain. J. Food Eng., 113(1):
156-166.
Belewu, M.A. and F. T. Babalola (2009). Nutrient enrichment of waste agricultural
residues after solid state fermentation using Rhizopus oligosporus. J. Appl.
Biosci., 13: 695-699.
Bello, A.A. and P. T. Fowoyo (2014). Effect of heat on the ascorbic acid content of dark
green leafy vegetables and citrus fruits. Afric. J. Food Sci. Technol., 5(4):
114-118.
Bennett, B. C. (2016). Plants as food. Encyclopaedia of life support systems. Retrieved
from http://www.eolss.net/sample-chapters/c09/e6- 118-07.pdf.
Berrueta, L. A., R. M. Alonso-Salces and K. Heberger (2007). Supervised pattern
recognition in food analysis. J. Chrom., 1158: 196-214.
Berti, C., M. Faber and C. M. Smuts (2014). Prevention and control of micronutrient
deficiencies in developing countries: current perspectives. Nutr. Diet. Suppl.,
6: 41-57.
Bian, Z. H., Q. C. Yang and W. K. Liu (2015). Effects of light quality on the
accumulation of phytochemicals in vegetables produced in controlled
environments: A review. J. Sci. Food Agric., 95: 869-877.
Boham, B. A. and R. Kocipai-Abyazan (1994). Flavonoids and condensed tannin from
leaves of Hawaiian Vccinium vaticulatum and V. calycinium. Pacific Sci., 48:
458-463.
Bouba, A. A., N. Y. Njintang, H. S. Foyet, J. Scher, D. Montet and C. M. F. Mbofung
(2012). Proximate composition, mineral and vitamin content of some wild
plants used as spices in Cameroon. Food Nutri. Sci., 3: 423-32.
Bradford, K. J. and J. J. Harada (2010). Special issue: translational seed biology: from
model systems to crop improvement. Plant Sci., 179: 553-553.
Buragohain J., V. B. Singh, B. C. Deka, A. K. Jha, K. Wanshnong and T. Angam (2013).
Collection and evaluation of some underutilized leafy vegetables of
Meghalaya. Ind. J. Hill Farm., 26(2): 111-115.
202
Bussmann, R. W. and D. Sharon (2006). Traditional medicinal plant use in northern Peru:
Tracking two thousand years of healing culture. J. Ethnobiol. Ethnomed., 2:
47.
Bvenura, C., A. J. Afolayan (2015). The role of wild vegetables in household food
security in South Africa: A review. Food Res. Int., 76: 1001-1011.
Cam, M., H. Yasar and G. Durmaz (2009). Classification of eight pomegranate juices
based on antioxidant activity measured by four methods. Food Chem., 112:
721-726.
Camacho-Corona, M. D. R., M. A. Ramirez-Cabrera, O. Gonzalez-Santigo, E. Garza-
Gonzalez, I. D. P. Palacios and J. Luna-Herrera (2008). Activity against drug
resistant Tuberculosis strains of plants used in Mexican traditional medicine to
treat Tuberculosis and other respiratory diseases. Phytoth. Res., 22: 82-85.
Camera, F. and C. A. Amaro (2003). Nutritional aspect of zinc availability. Int. J. Food
Sci. Nutr., 47: 143-151.
Cavender, A. (2006). Folk medicinal uses of plant foods in southern Appalchia United
States. J. Ethnopharmacol., 108: 74-84.
Chadare, F. J., A. R. Linnemann, J. D. Hounhouigan, M. J. R. Nout and M. A. J. S. Van-
Boekel (2009). Baobab food products: A review on their composition and
nutritional value. Critic. Rev. Food Sci. Nut., 49: 254-274.
Chatfield, C. and A. J. Collin (1980). Introduction to Multivariate Analysis. Chapman
and Hall in Association with Methuen, Inc. 733 Third Avenue, New York NY.
Cheema, U. B., J. I. Sultan, A. Javaid, P. Akhtar and M. Shahid (2011). Chemical
composition, mineral profile and in situ digestion kinetics of fodder leaves of
four native trees. Pak. J. Bot., 43: 397-404.
Cherney, J. H. and D. J. R. Cherney (2005). Agronomic responce of cool season grasses
to low intensity harvest management and low potassium fertility. Agron. J.,
97: 1216-1221.
Chiewchan, N., C. Praphraiphetch and S. Devahastin (2010). Effect of pretreatment on
surface topographical features of vegetables during drying. J. Food Eng., 101:
41-48.
Ching, L. Y. (2010). Effect of various cooking methods on nutritional value, antioxidant
activity and bioavailability of minerals in wild vegetables (Passiflora foetida
and Portulaca oleracea). Universiti Malaysia Sabah (Retrieved from
http://eprints.ums.edu.my/ 678).
Chionyedua, T. O., M. O. Anuoluwa and D. W. Adedoja (2009). The proximate and
mineral composition of three leafy vegetables commonly consumed in Lagos.
Afric. J. Biotechnol., 3(6): 102-107.
Cobb, G. P., K. Sands, M. Waters, B. G. Wixson and E. Dorward-King (2000). Toxic
effects of heavymetals. Environ. Toxicol. Chem. J., 19: 600-607.
203
Coruh, I., A. A. Gormez, S. Ercisli and S. Bilen (2007). Total phenolics, mineral
elements, antioxidant and antibacterial activities of some edible wild plants in
Turkey. Asian J. Chem., 19: 5755-5762.
Coskun, B., N. Gulsen and H. D. Umucalilar (2004). The nutritive value of Prangos
ferulacea. Grass Forag. Sci., 59: 711-717.
Courvalin, P. (2016). Why is antibiotic resistance a deadly emerging disease? Clin.
Microbiol. Infect. 22(5): 405-7.
Das, P., L. P. Devi and M. Gogoi (2009). Nutrient composition of some regional recipes
of Assam, India. Ethno-Med., 3: 111-117.
De-Boer, H. J. and C. Cotingting (2014). Medicinal plants for women's health care in
Southeast Asia: ameta- analysis of their traditional use, chemical constituents,
and pharmacology. J. Ethnopharmacol., 151: 747-767.
De-la-Pena, R. C., A. W. Ebert, P. Gniffke, P. Hanson and R. C. Symonds (2011).
Genetic adjustment to changing climates: vegetables. in crop adaptation to
climate change, 1st ed.; Yadav, S. S., R. J. Redden, J. L. Hatfield, H. Lotze-
Campen and A. E. Hall Eds.; John Wiley and Sons, Ltd.: Chichester, UK, pp:
396-410.
Delgado, M. E., A. I. Haza, A. Garcia and P. Morales (2009). Myricetin, quercetin, (+)-
catechin and (-)-epicatechin protect against N-nitrosamines-induced DNA
damage in human hepatoma cells. Toxicol., 23(7): 1292-1297.
Demir, H. (2006). Chemical composition of some wild (Polygonum cognatum,
Tragopoxgom reticulatus and Berberis vulgaris) plants collected from
Erzurum. Bahce 35, 55-60.
Den-Hartog, A. P., W. J. Van Staveren and I. D. Brouwer (2006). Food habits and
consumption in developing countries: manual for field studies. Wageningen:
Wageningen Academic Publishers.
DESA (2013). World population prospects, the 2012 revision. NewYork: Department for
economic and social affairs (June 1–4, Retrieved from http://scholar.google.
com/scholar?hl=en&btnG=Search&q=intitle:World+Population+Prospects:
+The+2012+Revision#1).
Deshmukh, S. and V. Rathod (2013). Nutritional evaluation of some wild edible tuberous
plants. Asian J. Pharmac. Sci., 6(2): 58-60.
Development statistics of Sindh (2011). Sindh bureau of statistics, bureau of statistics
complex, st-13, block-8, choudry khaleeq-uz-zaman road, kehkeshan Clifton,
Karachi-75600.
De-Vogel, S., V. Dindore, M. Van-Engeland, R. A. Goldbohm, P. A. Van-Den-Brandt
and M. P. Weijenberg (2008). Dietary folate, methionine, riboflavin, and
vitamin B-6 and risk of sporadic colorectal cancer. J. Nut., 138: 2372-2378.
204
Dinda, B., S. Debnath and Y. Harigaya (2007a). Naturally occurring iridoids. A review,
Part 1. Chem. Pharmac. Bull., 55: 159-222.
Dinda, B., S. Debnath and Y. Harigaya (2007b). Naturally occurring secoiridoids and
bioactivity of naturally occurring iridoids and secoiridoids. A review, Part 2.
Chem. Pharmac. Bull., 55: 689-728.
Djeridane, A., M. Yousfi, B. Nadjemi, D. Boutassouna, P. Stocker and N. Vidal (2006).
Antioxidant activity of some Algerian medicinal plants extracts containing
phenolic compounds. Food Chem., 97(4): 654-660.
Ebert, A.W. (2014). Potential of underutilized traditional vegetables and legume crops to
contribute to food and nutritional security, income and more sustainable
production systems. Sustain., 6(1): 319-35.
Ebrahimzadeh, M. A., S. J. Hosseinimehr, A. Hamidinia and M. Jafari (2008).
Antioxidant and free radical scavenging activity of Feijoa sallowiana fruits
peel and leaves. Pharmacol. Online., 1: 7-14.
Edogbanya, P. R. O. (2016). Comparative study of the proximate composition of edible
parts of Adansonia digitata L. obtained from Zaria, Kaduna State, Nigeria.
MAYFEB J. Bio., 1:1-6.
El-Amier, Y. A. and A. A. Ejgholi (2014). Fodder potentialities of three halophytes
naturally growing in Egypt. J. Environ. Sci., 43: 647-662.
Emebu, P. K. and J. U. Anyika (2011). Proximate and mineral composition of Kale
(Brassica oleracea) grown in Delta State, Nigeria. Pak. J. Nutr., 10: 190-194.
Ewere, E. G., O. E. Etim and U. Usunobun. (2017). Proximate composition, mineral
content and amino acid profile of Irvingia gabonensis O’Rorke baill leaf. Int.
J. Sci. World., 5(1): 23- 27.
Ezebilo, E. E. (2010). Conservation of a leafy vegetable important for communities in the
Nigerian rainforest. Forest Ecol. Manag., 259(8): 1660-1665.
Fan, S., C. Ringler, E. Nkonya and A. Stein (2012). Ensuring food and nutrition security
in a green economy. Washington, DC: International Food Policy Research
Institute (Retrieved from
http://www.ifpri.org/sites/default/files/publications/bp21notes.pdf).
FAO (2009). World summit on food security. (Rome).
FAO (2010). Rome. Sustainable diet and biodiversity.
FAO (2013a). Linkages between biodiversity, food and nutrition. Commission on
Genetic Resources for Food and Agriculture. Fourteenth Regular Session.
Rome, Food and Agriculture Organization of the United Nations.
http://www.fao.org/docrep/ meeting/027/mf561e.pdf Accessed 25/10/2013.
FAO (2013b). Narrowing the nutrient gap: investigating in agriculture to improve dietary
diversity. Rome, Food and Agriculture Organization of the United Nations.
205
Farooq, S., A. Barki, M. Y. Khan, H. Fazal (2012). Ethnobotanical studies of the flora of
Tehsil Birmalin south Waziristan Agency, Pakistan. Pak. J. Weed Sci. Res.,
18: 277-291.
Fasakin, K. (2004). Proximate composition of Bungu (Cerototheca sesamoide Endl)
leaves and seeds. Biokem., 16(2): 88-92.
Fasuyi, A. O. (2006). Nutritional potentials of some tropical vegetable meals. Chemical
characterization and functional properties. Afr. J. Biotechnol., 5: 49-53.
Fentahun, M. T. and H. Hager (2009). Exploiting locally available resources for food and
nutritional security enhancement: wild fruits diversity, potential and state of
exploitation in the Amhara region of Ethiopia. Food Sec., 1: 207-219.
Fernando, S. M. and P. A. Murphy (1990). HPLC determination of thiamin and riboflavin
in soybeans and tofu. J. Agric. Food Chem., 38: 163-167.
Figueroa, B. M., P. Tittonell, K. E. Giller and O. Ohiokpehai (2009). The contribution of
traditional vegetables to household food security in two communities of
Vihiga and Migori Districts, Kenya. Proc. IS on Underut. Plants Acta Hort.,
pp: 806.
Fink, A. (1995). The survey Handbook. Sage Publication, Thousand Oaks, California,
USA.
Fink, A. (2003). How to sample in surveys. The survey kit, 2nd
edition. Sage Publication,
Thousand Oaks, California, USA.
Flyman, M. and A. Afolayan (2008). Maturity on the mineral content of the leaves of
Momordica balsamina L. and Vigna unguiculata subsp. sesquipedalis (L.)
Verdc. J. Food Qual., 31: 661-671.
Folarin, O. M. and O. C. Igbon (2010). Chemical composition of Enterolobium
cyclocarpum (Jacq.) Griseb. seed and physiochemical properties of the oil
extracts. Hamdard Medic., 53: 21-26.
Frison, E. A., J. Cherfas and T. Hodgkin (2011). Agricultural biodiversity is essential for
a sustainable improvement in food and nutrition security. Sustain., 3: 238-253.
Fuleky, G. (2016). Cultivated plants primarily as food sources. Encyclopaedia of life
support systems. Retrived from http://www.eolss.net/sample-chapters/c10/E5-
02.pdf.
Gafar, M. K., A. U. Itodo, F. A. Atiku, A. M. Hassan and I. J. Peni (2011). Proximate and
mineral composition of the leaves of hairy indigo (Indigofera astragalina).
Pak. J. Nut., 10(2): 168-175.
Gahler, S., K. Otto and V. Bohm (2003). Alterations of vitamin C, total phenolics, and
antioxidant capacity as affected by processing tomatoes to different products.
J. Agricult. Food Chem., 51: 7962-7968.
206
Garcia, E. and D. M. Barrett (2002). Preservative treatments for freshcut fruits and
vegetables. In O. Lamikanra (Ed.), Fresh-cut fruits and vegetables. Science,
technology and market. Boca Raton, FL: CRC Press.
Garcia-Herrera, P., M.C. Sanchez-Mata, M. Camara, V. Fernandez-Ruiz, C. Diez-Marque
s, M. Molina, J. Tardio (2014b). Nutrient composition of six wild edible
Mediterranean Asteraceae plants of dietary interest. J. Food Compos. Anal.,
34: 163-170.
Garcia-Herrera, P., P. Morales, V. Fernandez-Ruiz, M. C. Sanchez-Mata, M. Camara, A.
M. Carvalho, A. M., I.C.F.R. Ferreirab, M. Pardo-de-Santayanac, M. Molinad
and J. Tardio (2014a). Nutrients, phytochemicals and antioxidant activity in
wild populations of Allium ampeloprasum L., a valuable underutilised
vegetable. Food Res. Int., 62: 272-279.
Gbadamosi, I.T., J. O. Moody and A. M. Lawal (2011). Phytochemical screening and
proximate analysis of eight ehnobotanicals used as antimalaria remedies in
Ibadan, Nigeria. J. Appl. Biosci., 44: 2967-2971.
Geeta, R. and M. L. Sharma (2015). Nutritional value of traditional wild vegetables used
by the Kinnaura tribals of Himachal Pradesh, India. Int. J. Pharma. Biosci.,
6(2): 551-558.
Ghani, A., Z. Ali, M. Ishtiaq, M. Maqbool and S. Parveen (2012). Estimation of macro
and micro nutrients in some important medicinal plants of Soon Valley,
District Khushab, Pakistan. Afr. J. Biotechnol., 11: 14386-14391.
Global Food Security (2013). Strategic plan 2011–2016. Retrieved from
http://www.foresightfor development.org/sobipro/55/930-global-food-
security-strategic-plan-2011-2016.
GOP (2011-12). Agricultural Statistics of Pakistan. Pakistan Bureau of Statistics.
Gopalan, C., B. V. Sastri and S. C. Balasubramanian (1989). Nutritive value of Indian.
FOODS. Hyderabad, India: Ind. Coun. Med. Res., 2(1): 392-396.
Gorny, J. R., M. I. Gil, A. A. Kader (1998). Postharvest physiology and quality
maintenance of fresh-cut pears. Acta Hort., 464: 231-236.
Gorny, J. R., R. A. Cifuentes, B. Hess-Pierce and A. A. Kader (2000). Quality changes in
fresh-cut pear slices as affected by cultivar, ripeness stage, fruit size, and
storage regime. J. Food Sci., 65(3): 541-544.
Greenfield, H. and D.A. Southgate (2003). Food Composition Data. Production
Management and Use, 2nd Edition, Rome, FAO.
Grivetti, L. E. and B. M. Ogle (2000). Value of traditional foods in meeting macro and
micronutrient needs: the wild plant connection. Nutr. Res. Rev., 13: 31-46.
Guarrera, P. M. and V. Savo (2013). Perceived health properties of wild and cultivated
food plants in local and popular traditions of Italy: a review. J. Ethnopharm.,
146: 659-680.
207
Guil-Guerrero, J. L. (2014). The safety of edible wild plants: Fuller discussion may be
needed. J. Food Compos. Anal., 35:18-20.
Gupta, S., A. J. Lakshmi, M. N. Manjunath, J. Prakash (2005). Analysis of nutrient and
antinutrient content of underutilized green leafy vegetables. LWT 38 (4): 339-
345.
Hadjichambis, A.C., D. Paraskeva-Hadjichambi, A. Della, M. Elena Giusti, C. De-Pas-
quale, C. Lenzarini, E. Censorii, M. R. Gonzales-Tejero, C. P. Sanchez-
Rojas, J. Ramiro-Gutierrez, M. Skoula, C. Johnson, A. Sarpaki, M.
Hmamouchi, S. Jorhi, M. El-Demerdash, M. El-Zayat and A. Pieroni (2008).
Wild and semi- domesticated food plant consumption in seven circum-
Mediterranean areas. Int. J. Food Sci. Nutr., 59: 383-414.
Hailu, A. A. and G. Addis (2016). The content and bioavailability of mineral nutrients of
selected wild and traditional edible plants as affected by household
preparation methods practiced by local community in Benishangul Gumuz
regional State, Ethiopia. 2016: 1-7.
Hameed, I., G. Dastagir and F. Hussain (2008). Nutritional and elemental analyses of
some selected medicinal plants of the family Polygonaceae. Pak. J. Bot., 40:
2493-2502.
Hanif, R., Z. Iqbal, M. Iqbal, S. Hanif and M. Rasheed (2006). Use of vegetable as
nutritional role in human health. J. Agric. Biol. Sci., 1: 18-22.
Harborne, J. B. (1993). Phytochemical methods: A guide to modern technique in plant
analysis. Chapman and Hall; New York.
Hart, T., and I. Vorster (2006). Indigenous knowledge on the South African landscape:
Potentials for agricultural development. In U. Pillay (Ed.), Cape Town:
Human Sciences Research Council.
Hassan, L. G. and K. J. Umar (2006). Nutritional value of Balsam Apple (Momordica
balsamina L.) leaves. Pak. J. Nutr., 5(6): 522-529.
Hassan, S. W., R. A. Umar, I. K. Matazu, H. M. Maishanu, A. Y. Abbas A. A.and Sani
(2007). The effect of drying method on the nutrients and non- nutrients
composition of the leaves of Leptadenia hastate (Aschipiadaceae). Asian J.
Biochem., 2: 188-192.
Hayat, M. Q., M. A. Khan, M. Ahmad, N. Shaheen, G. Yasmin and S. Khter (2008).
Ethnotaxonomical approach in the identification of useful medicinal flora
Tehsil Pindigheb (District Attock) Pakistan.” Ethnobot. Res. Appl., 6: 35-62.
He, F. J. and G. A. MacGregor (2008). Beneficial effects of potassium on human health.
Physiolog. Planta., 133(4): 725-735.
Heinrich, M., J. Kufer, M. Leonti and M. Pardo-de-Santayana (2006a). Ethnobotany and
ethnopharmacology- Interdisciplinary links with the historical sciences. J. Eth-
nopharmacol., 107: 157-160.
208
Heinrich, M., S. Nebel, M. Leonti, D. Rivera and C. Obon (2006b). Local food
nutraceuticals: bridging the gap between local knowledge and global needs.
Forum Nutr., 59: 1-17.
Hervert-Hernandez, D., O.P. Garcia, J. L. Rosado and I. Goni (2011). The contribution of
fruits and vegetables to dietary intake of polyphenols and antioxidant capacity
in a Mexican rural diet: importance of fruit and vegetable variety. Food Res.
Int., 44: 1182-1189.
Hoeschle-Zeledon, I. and P. Bordoni (2003). Approaches and decision steps for the
promotion and development of underutilized plant species. Global Facilitation
Unit for Underutilized Species. Rome, Italy.
Horo, S. and S. Topno (2015). Study and analysis of nutritional value of some wild and
semi wild edible plants consumed by “HO” tribes of W. Singhbhum district,
Jharkhand, India. Int. J. Herb. Med., 3(5): 25-32.
Horwitz, W. (2000). Official Method of Analysis of AOAC International. 17th Edition.
Vol. II AOAC International. Maryland, USA.
Hotz, C. and K. H. Brown (2004). Assessment of the risk of zinc deficiency in
populations and options for its control. Food Nutr. Bull., 25: 99-204.
Hughes, J. A. and A. W. Ebert (2013). Research and development of underutilized plant
species: the role of vegetables in assuring food and nutritional security. In
proceedings of the 2ndinternational symposium on underutilized plant
species: crops for the future—beyond food security; Massawe, F., S. Mayes,
P. Alderson Eds.; International Society for Horticultural Sciences (ISHS):
Korbeek-Lo, Belgium, 2: 79-91.
Humadi, S. S. and V. Istudor (2008). Quantitative analysis of bioactive in Hibiscus
subdarifolia L. extracts: notes 1 quantitative analysis of flavonoids. FARMA.
LVI., 6: 699- 704.
Humphery, A. M. (2004). Chlorophyll as a color and functional ingredient. J. Food Sci.,
69: 422-425.
Husain, Z. S., R. N. Malik, M. Javaid and S. Bibi (2008). Ethnobotanical properties and
uses of medicinal plants of Morgha Biodiversity Park, Rawalpindi. Pak. J.
Bot., 40: 1897-1911.
Hussain, F. and M. J. Durrani (2009). Nutritional evaluation of some forage plants from
Harboi rangeland, Kalat, Pakistan. Pak. J. Bot., 41: 1137-1154.
Hussain, J., A. L. Khan, N. Rehman, Z. Hussain, F. Khan and Z. K. Shinwari (2009a).
Proximate and nutrient analysis of selected medicinal plant species of
Pakistan. Pakistan J. Nut., 8: 620 -624.
Hussain, J., A. L. Khan, N. U. Rehman, M. Hamayun, T. Shah, M. Nisar, T. Bano, Z. K.
Shinwari and I. J. Lee (2009b). Proximate and nutrient analysis of selected
209
vegetable species: a case of Karak Region, Pakistan. Afric. J. Biotechnol.,
8(12): 2725-2729.
Hussain, J., N. Rehman, A. L. Khan, H. Hussain, A. Ahmed, L. Ali, F. Sami and Z. K.
Shinwari (2011). Determination of macro and micronutrients and nutritional
prospectsof six vegetable species of Mardan, Pakistan. Pak. J. Bot., 43(6):
2829-2833.
Hussain, J., R. Ullah, N. U. Rehman, K. Muhammad, F. Khan, S. T. Hussain and S.
Anwar (2010). Endogenous transitional metal and proximate analysis of
selected medicinal plants from Pakistan. J. M. Plants Res., 4: 267-270.
Idah, P. A., E. S. A. Ajisegiri and M. O. Yisa (2007). Fruits and vegetables handling and
transportation in Nigeria. Aust. J. Technol., 10: 175-183.
Igwe, K., C. E. Ofoedu, D. C. Okafor, E. N. Odimegwu, I. M. Agunwah and V. S. Igwe
(2015). Comparative proximate analysis of some green leafy vegetables from
selected communities of Rivers and Imo State, Nigeria. Int. J. Basic Appl.
Sci., 4 (2): 55-61.
Ihenacho, K. (2009) Nutritional composition of some leafy vegetables consumed in Imo
State, Nigeria. J. Appl. Sci. Environ. Manag., 13: 35-38.
Ilelaboye, N. O. A., I. A. Amoo and O. O. Pikuda (2013). Effect of cooking methods on
mineral and anti nutrient composition of some green leafy vegetables. Arch.
Appl. Sci. Res., 5(3): 254-260.
Imran, M., F. N. Talpur, M. I. Jan, A. Khan and I. Khan (2007). Analysis of nutritional
components of some wild edible plants. J. Chem. Soc. Pak., 29(5): 500-505.
Indrayan, A. K., S. Sharma, D. Durgapal, N. Kumar and M. Kumar (2005).
Determination of nutritive value and analysis of mineral elements for some
medicinally valued plants from Uttaranchal. Curr. Sci., 89: 1252-1255.
Ingram, J. S. I. (2011). From food production to food security: Developing
interdisciplinary, regional-level research. Wageningen University.
Insel, P., D. Ross, K. Mcmahon and M. Bernstein (2011). Nutrition, Jones and Bartlett
Publishers, Sudbury, MA.
Io, O. I. (2012). Evaluation of iron, zinc, sodium and phytate contents of commonly
consumed indigenous foods in Southwest Nigeria. J. Nut. Food Sci., 2: (10).
Ishida, H., H. Suzuno, N. Sugiyama, S. Innami, T. Todokoro and A. Maekawa (2000).
Nutritional evaluation of chemical component of leaves, stalks and stemss of
sweet potatoes (Ipomoea batatas poir). Food Chem., 68: 359-367.
Ismail, A., Z. M. Marjan and C. W. Foong (2004). Total antioxidant activity and phenolic
content in selected vegetables. Food Chem., 87: 581-586.
210
Isong, E. U., S. A. R. Adewusi, E. U. Nkwanga, E. E. Umoh and E. E. Offiong (1999).
Nutritional and phytogeriatological studies of three variation of Gnetum
africanum. Food Chem., 64: 489-493.
Jabeen, S., M. T. Shah, S. Khan and M. Q. Hayat (2010). Determination of major and
trace elements in ten important folk therapeutic plants of Haripur basin, Pak.
J. Med. Plant Res., 4(7): 559-566.
Jackson, L. E., U. Pascual and T. Hodgkin (2007). Utilizing and conserving
agrobiodiversity in agricultural landscapes. Agric. Ecosyst. Environ., 121:
196-210.
Jain, S. and M. Gupta (2013). Biotechnology of neglected and underutilized crops;
Springer: Berlin, Germany.
James, C. S. (1995). Analytical chemistry of food. Seale-Hayne Faculty of Agriculture,
Food and Land use, Department of Agriculture and Food studies, University
of Polymouth, UK. 1: 96-97.
Jansen-van-Rensburg, W., I. H. J. Vorster, J. J. B. Van Zijl and L. S. Venter (2007).
Conservation of African leafy vegetables in South Africa. Afric. J. Food,
Agric. Nut. Develop., 7(4): 1-13.
Jayanti, K. Agarwal and P. Saini (2013). Nutritional assessment of leaves of wild edible
plant Urtica ardence. Ind. J. Pharma. Bio. Res., 1(1): 53-59.
Jellinek, G. and E. Horwood (1985). Sensory evaluation of food: theory and practice.
International Publishers in Science and Technology, Chichester, England.
Jimoh, F., A. Adedapo, A. Aliero and A. J. Afolayan (2010). Polyphenolic and biological
activities of leaves extracts of Argemone subfusiformis (Papaveraceae) and
Urtica urens (Urticaceae). Rev. Biol. Trop., 58(4):1517-1531.
Kabir, H. (1994). Fresh-cut vegetables. In A. L. Brods and V. A. Herndon (Eds.),
Modified atmosphere food packaging Naperville, Illinois: Institute of
Packaging Professionals pp: 155-160.
Kagale, L. and A. Sabale (2014). Nutritional composition and antioxidant potential of
coastal, wild leafy vegetables from Ratnagiri District of Maharashtra.World J.
Pharm. Sci. 3: 890-897.
Kakati P., S. C. Deka, D. Kotoki and S. Saikia (2010). Effect oftraditional methods of
processing on the nutrient contentsand some antinutritional factors in newly
developed cultivars of green gram (Vigna radiata L.) and black gram (Vigna
mungo L.) of Assam, India, Int. Food Res. J., 17(2): 377-384.
Kaliora, A. C., C. Batzaki, M. G. Christea, and N. Kalogeropoulos (2015). Nutritional
evaluation and functional properties of traditional composite salad dishes.
LWT - Food Sci. Technol., 62(1): 775-782.
Kalita, P., H. Tag, H. N. Sarma and A. K. Das (2014). Evaluation of nutritional potential
of five unexplored wild edible food plants from Eastern Himalayan
211
biodiversity hotspot region (India). Int. J. Biol. Food Vet. Agric. Eng., 8: 203-
206.
Kathirvel, A., A. Rai, G. Maurya, and V. Sujatha. (2014). Dryopteris cochleata rhizome:
a nutritional source of essential elements, phytochemicals, antioxidants and
antimicrobials. Int. J. Pharm. Pharm. Sci., 6: 179–188.
Kaya, H. O. and M. Masoga (2005). Balanced literacy: Enhancing the school curriculum
through African indigenous knowledge system. IKS Programme. North West
University.
Kayode, A. O. (2012). Chemical and phytochemical profile of some uncommon green
leafy vegetables consumed in South West, Nigeria. J. Environ. Sci. Toxicol.
Food Technol., 1(3): 22-26.
Keatinge, J. D. H., F. Waliyar, R. H. Jamnadass, A. Moustafa, M. Andrade, P. Drechsel,
J. D. A. Hughes, K. Palchamy and K. Luther (2010). Re-learning old lessons
for the future of food by bread alone no longer: Diversifying diets with fruit
and vegetables. Crop Sci., 50: 51-62.
Kebu, B. and K. Fassil (2006). Ethnobotanical study of wild edible plants in Derashe and
Kucha Districts, South Ethiopia. J. Ethnobiol. Ethnomed., 2: 53.
Keith, M. (1992). Edible wild plants. Lantern, 41(1).
Keller, G. B., H. Mndiga and B. L. Maass (2004). Production and consumption issues of
traditional vegetables in Tanzania from the farmers’ point of view. Seminar
presented at Deutscher Tropentag, 5–7 October 2004, Berlin, Germany. Book
of Abstracts, pp: 288.
Keller, G. B., H. Mndiga and B. L. Maass (2005). Diversity and genetic erosion of
traditional vegetables in Tanzania from the farmer’s point of view. Plant Gen.
Res., 3(3): 400-413.
Khalil, I. A. and F. R. Durrani (1990). Nutritional evaluation of tropical legume and
cereal forages grown in Pakistan. Trop. Agric., 67(4): 313-316.
Khan, A. A. (2012). A draft strategic frame work to arrest the plight of medicinal plants
in Pakistan. In: Proceeding of PARC and TASO-PGR Work shop on
Conservation and Sustainable Utilization of Medicinal Plants in Pakistan.
National Herbarium PARC, Islamabad, Pakistan, pp: 8-11.
Khan, N., A. Sultana, N. Tahir and N. Jamila (2013). Nutritional composition, vitamins,
minerals and toxic heavy metals analysis of Trianthema portulacastrum: a
wild edible plant from Peshawar, Khyber Pakhtunkhwa, Pakistan. Afr. J.
Biotechnol., 12(42): 6079-6085.
Kibar, B. and S. Temel (2016). Evaluation of mineral composition of some wild edible
plants growing in the eastern Anatolia region grasslands of turkey and
consumed as vegetable. J. Food Process. Pres., 40: 56-66.
212
Kidane, B., L. J. G. Van-der-Maesen, Z. Asfaw, M. S. M. Sosef and V. T. Andel (2015).
Wild and semi-wild leafy vegetables used by the Maale and Ari ethnic
communities in southern Ethiopia. Gen. Resour. Crop Evol., 62(2): 221-34.
Koca, I., I. Hasbay, S. Bostanci, V. A. Yilmaz and A. F. Koca (2015). Some wildedible
plants and their dietary fiber contents. Pak. J. Nutr., 14(4): 188-194.
Kolodziej, H. and A.F. Kiderlen (2005). Antileishmanial activity and immune
modulatory effects of tannins and related compounds on Leishmania
parasitised RAW 2647 cells. Phytochem., 66(17): 2056-2071.
Kongkachuichai, R., R. Charoensiri, K. Yakoh, A. Kringkasemsee and P. Insung (2015).
Nutrients value and antioxidant content of indigenous vegetables from
Southern Thailand. Food Chem., 173: 838-846.
Krinsky, N. I. and J. E. Johnson (2005). Carotenoid actions and their relation to health
and disease. Mol. Asp. Med., 26: 459-516.
Kubmarawa, D., G. A. Wase and O. G. Ayinla (2007). Preliminary studies on
phytochemical analysis and antimicrobial evaluation of extracts of
Commiphora kerstingii, J. Chem. Soc. Nigeria., 32(1): 38-40.
Kumar, S. S., P. Manoj and P. Giridhar (2015). Nutrition facts and functional attributes of
foliage of Basella spp. LWT - Food Sci. Technol., 64(1): 468-474.
Kumari, A., A. K. Parida, J. Rangani and A. Panda (2017). Antioxidant activities,
metabolic profiling, proximate analysis, mineral nutrient composition of
salvadora persica fruit unravel a potential functional food and a natural source
of pharmaceuticals. Front. Pharmacol., 8(61): 1- 14.
Kunwar, R. M., B. K. Nepal, H. B. Kshhetri, S. K. Rai and R. W. Bussmann (2006).
Ethnomedicine in Himalaya: A case study from Dolpa, Humla, Jumla, and
Mustang districts of Nepal. J. Ethnobiol. Ethnomed., 2-27: 1-6.
Kurozawa, L. E., Hubinger, M. Dupas, Park and K. Jin (2012). Glass transition
phenomenon on shrinkage of papaya during convective drying. J. Food Eng..
108 (1): 43- 50.
Labadarios, D., N. Steyn, E. Maunder, U. Macintyre, G. Gericke, G., R. Swart, J.
Huskisson, A. Dannhauser, H. H. Vorster, A. E. Nesmvuni and J. H. Nel
(2005). The national food consumption survey (NCFS): South Africa 1999.
Pub. Health Nut., 8(5):533-43.
Labadarios, D., R. Swart, E. Maunder, H. Kruger, G. Gericke, P. M. N. Kuzwayo, P. R.
Ntsie, N. P. Steyn, I. Schloss, M. A. Dhansay, P. L. Jooste, A. Dannhauser, J.
H. Nel, D. Molefe and T. J. W. Kotze (2008). Executive summary of the
national food consumption survey fortifi cation baseline (NFCS-FB-I) South
Africa, 2005. South Afric. J. Clinic. Nut., 21(3): 245-300.
Ladeji, O., C. U. Akin, and H. A. Umaru (2004). Level of antinutritional factors in
vegetables commonly eaten in Nigeria. Afric. J. Nat. Sci., 7: 71-73.
213
Laker, M. C. (2007). African leafy vegetables in South Africa. Water SA., 33(3): 311-
315.
Lakshanasomya, N. (1998). Determination on Vitamin C in Some Kinds of Food by
HPLC. Bull. Dept. Med. Sci., 40(3): 347-357.
Lee, J. C., K. Y. Lee, J. N. Kim (2004). Extract from Rhus verniciflua Stokes is capable
of inhibiting the growth of human lymphoma cells. Food Chem. Toxicol., 9:
1383-1388.
Lee, S. J. and K. T. Lim (2006). 150 kDa glycoprotein isolated from Solanum nigrum
Linn stimulates caspase-3 activation and reduces inducible nitric oxide
production in HCT-116 cells. Toxicol. in vitro., 20: 1088-1097.
Leedy, P. D. and J. E. Ormrod (1993). Practical research: planning and design. Prentice
Hall, New Jersy, UK.
Legwaila, G. M., W. Mojeremane, M. E. Madisa, R. M. Mmolotsi and M. Rampart
(2011). Potential of traditional food plants in rural household food security in
Botswana. J. Hort. Forest., 3(36): 171-177.
Leite, J. F. M., J. A. D. Silva, T. S. Gadelha, C. A. Gadelha, J. P. D. S. Junior (2009).
Nutritional value and antinutritional factors of foliaceous vegetable Talinum
fruticosum. Revista do Instit. Adolfo Lutz., 68(3): 341-345.
Lephole, M. M. (2004). Uses and nutritional value of traditional vegetables consumed as
traditional foods in Lesotho. Unpublished research thesis, University of the
Free State, Bloemfontein, South Africa.
Lewu, F. B., S. Mavengahama (2010). Wild vegetables in northern Kwazulu Natal, South
Africa: Current status of production and research needs. Scient. Res. Essay.,
5(20): 3044-3048.
Lewu, M. N. and L. Kambizi (2015). Nutritional assessment of selected leafy vegetables.
international conference on biotechnology and food technology (ICBFT'15)
July 14-15, 2015 Harare (Zimbabwe). Pp: 80-84.
Liu, C. W., K. H. Lin and Y. M. Kuo (2003). Application of factor analysis in the
assessment of groundwater quality in a Blackfoot disease area in Taiwan. Sci.
Total Environ., 313: 77-89.
Liu, Y. T., C. O. Perera and V. Suresh (2007). Comparison of three chosen vegetables
with others from South East Asia for theit lutein and zeaxanthin content. Food
Chem., 101: 1533-1539.
Lola, A. (2009). The effect of boiling on the nutrients and anti-nutrients in two
nonconventional vegetables. Pak. J. Nut., 8(9): 1430-1433.
Lonsdale, D. (2006). A review of the biochemistry, metabolism and clinical benefits of
thiamn(e) and its derivatives. Evid Based Compl. Alternat Med., 3(1): 49-59.
214
Luczaj, L. (2010). Changes in the utilization of wild green vegetables in Poland since the
19th century: a comparison of four ethnobotanical surveys. J. Ethnopharm.,
128: 395-404.
Lui, D., J. Shi, A. C. Ibarra, Y. Kakuda and S. J. Xue (2008). The scavenging capacity
and synergistic effects of lycopene, vitamin E, vitamin C, and β-carotene
mixtures on the DPPH free radical. LWT - Food Sci. Technol., 41: 1344-
1349.
Lwoga, E. T., P. Ngulube and C. Stilwell (2010). Managing indigenous knowledge for
sustainable agricultural development in developing countries: Knowledge
management approaches in the social context. Int. Inform. Lib. Rev., 42(3):
174-185.
Mahapatra, A. K. and P. C. Panda (2012). Wild edible fruit diversity and its significance
in the livelihood of indigenous tribals: evidence from eastern India. Food Sec.,
4: 219-234.
Mahmood, A., A. Mahmood and A. Tabassum (2011a). Ethnomedicinal survey of plants
from District Sialkot, Pakistan. J. Appl. Pharm., 2(3): 212-220.
Mahmood, A., A. Mahmood, H. Shaheen, R. A. Qureshi, Y. Sangi and S. A. Gilani
(2011b). Ethnomedicinal survey of plants from district Bhimber Azad Jammu
and Kashmir, Pakistan. J. Med. Plant Res., 5(11): 2348-2360.
Mahmood, A., A. Mahmood, R. N. Malik (2012). Indigenous knowledge of medicinal
plants from Leepa valley, Azad Jammu and Kashmir, Pakistan. J.
Ethnopharm., 30;143(1): 338-346.
Mahmood, A., R. A. Qureshi, A. Mahmood, Y. Sangi, H. Shaheen, I. Ahmad and Z.
Nawaz (2011c). Ethnobotanical survey of common medicinal plants used by
people of district Mirpur, AJK, Pakistan. J. Med. Plant Res., 5(18): 4493-
4498.
Mahmood, A., R. N. Malik and Z. K. Shinwari (2013). Indigenous knowledge of
medicinal plants from Gujranwala district, Pakistan. J. Ethnopharm., 148(2):
714-723.
Maki, K. C., C. L. Pelkman, E. T. Finocchiaro, K. M. Kelley, A. L. Lawless, A. L. Schild
and T. M. Rains (2012). Resistant Starch from High-Amylose Maize Increases
Insulin Sensitivity in Overweight and Obese Men. J. Nut., 142: 717-723.
Maunder, E. M. W. and J. L. Meaker (2007). The current and potential contribution of
home-grown vegetables to diets in South Africa. Water SA, 33(3): 401–406.
Mavengahama, S., M. McLachan and W. D. Clercq (2013). The role of wild vegetable
species in household food security in maize based subsistence cropping
systems. Food Sec., 5: 227-233.
Maxted, N., M. E. Dulloo, B. V. Ford-Lloyd, L. Frese, J. M. Iriondo and M. A. A. P. Car-
valho (2011b). Agro biodiversity conservation: Securing the diversity of crop
215
wild relatives and land races. School of Biosciences. The University of
Birmingham, Edgbaston, Birmingham, B15 2TT, UK.
Maxted, N., Z. I. Akparov, M. Aronsson, A. Asdal, A. Avagyan, B. Bartha, D. Bene-
dikova, T. Berishvili, R. Bocci, Z. Bullinska-Radomska, J. Cop, T. Curtis, K.
Daugstad, S. Dias, M. C. Duarte, S. Dzmitryeva, J. Engels, D. A. Fasoula, N.
Ferant, L. Frese, P. Freudenthaler, R. Hadas, L. Holly, A. Ibraliu, J. M.
Iriondo, S. Ivanovska, T. Jinjikhadze, G. Kamari, S. P. Kell, C. Kik, L. Koop,
H. Korpelainen, K. Kristiansen, A. Kyratzis, J. Labokas, L. Maggioni, J.
MagosBrehm, E. Mal-oupa, J. J. R. Martinez, P. M. R. M. Moreira, M.
Musayev, M. Radun, P. Ralli, D. Sandru, K. Sarikyan, B. Schierscher-Viret,
T. Smekalova, Z. Stehno, T. Stoilova, S. Strajeru, A. Tan, M. Veteläinen, R.
Vogel, G. Vorosvary and V. Negri (2011a). Current and future threats and
opportunities facing European crop wild relative and land race diversity. Agro
biodiversity conservation: securing the diversity of crop wild relatives and
land races. Pp: 333-353.
Mazumdar, B. C. and K. Majumder (2003). Methods on physicochemical analysis of
fruits. Uni. College of Agric. Calcutta University. Pp: 108-109.
Mazzeo, T., M. Paciulli, E. Chiavaro, A. Visconti, V. Fogliano, T. Ganino and N.
Pellegrini (2015). Impact of the industrial freezing process on selected
vegetables -Part II. Colour and bioactive compounds. Food Res. Int., 75: 89-
97.
McCouch, S. (2013). Feeding the future. Nature, 499: 23-24.
Menendez-Baceta, G., L. Aceituno-Mata, J. Tardio, V. Reyes-Garcia and M. Pardo-de-
San- Tayana (2012). Wild edible plants traditionally gathered in Gorbeialdea
(Biscay, Basque Country). Gen. Resour. Crop Evol., 59:1329-1347.
Menesatti, P., F. Antonucci, F. Pallottino, G. Roccuzzo, M. Allegra, F. Stagno and F.
Intrigliolo (2010). Estimation of plant nutritional status by VIS-NIR
spectrophotometric analysis on orange leaves. Biosyst. Eng., 105: 448-454.
Mertz, C., A. L. Gancel, Z. Gunata, P. Alter, C. Dhuique-Mayer, F. Vaillant, A. N. Perez,
J. Ruales and P. Brat (2009). Phenolic compounds, carotenoids and
antioxidant activity of three tropical fruits. J. Food Compos. Anal., 22: 381-
387.
Middleton, J. R. E., C. Kandaswami, T. C. Theoharides (2008). The effects of plant
flavonoids on mammalian cells: Implication for inflammations, heart disease
and cancer. Pharmacol. Rev., 52: 673-751.
Modi, M., A. Modi and S. Hendriks (2006). Potential role for wild vegetables in
household food security: A preliminary case study in KwaZulu-Natal, South
Africa. Afric. J. Food Agric. Nut. Develop., 6(1): 1-13.
Mohammed, M. I. and N. Sharif (2011). Mineral composition of some leafy vegetables
consumed in Kano, Nigeria. Niger J. Basic Appl. Sci., 19(2): 208-212.
216
Mohankumar, J. B., A. J. Gladious and M. Velvizhi. (2017). Antioxidant content of
selected medicinal plants used by Kaani Tribes of Kanyakumari District in
Tamilnadu India. J. Food Nutr. Res., 5(3): 180- 186.
Morales, P., A. M. Carvalho, M. C. Sanchez-Mata, M. Camara, M. Molina and I. C. F. R.
Ferreira (2011). Tocopherol composition and antioxidant activity of Spanish
wild vegetables. Gen. Res. Crop Evol., 59: 851-863.
Morales, P., I. C. F. R. Ferreira, A. M. Carvalho, M. C. Sanchez-Mata, M. Camara, V.
Fernández-Ruiz, M. Pardo-de-Santayanac and J. Tardio (2013).
Mediterranean non-cultivated vegetables as dietary sources of compounds
with antioxidant and biological activity. LWT—Food Sci. Technol., 55: 389-
395.
Mouton, J. and H. C. Marais (1993). Basic concepts in the methodology of the social
sciences. HSRC series in methodology. HSRC, Pretoria, South Africa.
Mrema, C. G., and S. R. Rolle (2002). Status of the postharvest sector and its contribution
to agricultural development and economic growth. In: 9th JIRCAS
International Symposium - Value Addition to Agricultural Product, pp: 13-20.
Mudambi, S. R. and M. V. Rajagopal (1980). Fundamentals of foods and nutrition. Wiley
Eastern Ltd., New Delhi.
Mujumdar, A., M. L. Passos (2000). Developments in Drying. Bangkok Kasetsart
University Press.
Musa, K. Y., A. J. Ahmend, H. Ibrahim, G. Arowosiaye and O. S. Olaitola (2000).
Phytochemical and antimicrobial studies of leaves of Acalypha racemosa.
Nig. J. Nat. Prod. Med., 4: 67-69.
Musinguzi, E., J. K. Kikafunda and B. T. Kiremire (2006). Utilization of indigenous food
plants in Uganda: A case study of South Western Uganda. Afric. J. Food
Agric. Nut. Develop., 6(2): 1-14.
N’danikou, S., E. G. Achigan-Dako and J. L. G. Wong (2011). Eliciting local values of
wild edible plants in Southern Benin to identify priority species for
conservation. Eco. Bot., 65(4): 381-95.
Nasir, E. and S.I. Ali (2005). Flora of Pakistan. Pak. Agri. Res. Council Islamabad.
Nawirska, A., A. Figiel, A. Z. Kucharska, A. Sokol-Letowska and A. Biesiada (2009).
Drying kinetics and quality parameters of pumpkin slices dehydrated using
different methods. J. Food Eng., 94: 14- 20.
Ndamitso M. M., M. B. Etsuyankpa, J. O. Jacob, J. T. Mathew, E. Y Shaba and K. C.
Olisedeme (2015). The nutritional values and functional properties of wild
Ipomoea aquatic (water spinach) found in the fadama areas of Minna, Niger
State, Nigeria. Acad. Res. Int., 6(4): 1-8.
Ndlovu, J. and A. J. Afolayan (2008). Nutritional analysis of South African wild
vegetable Corchorus olitorius L. Asian J. Plant Sci., 7: 615-618.
217
Nesamvuni, C., N. Steyn and M. Potgieter (2001). Nutritional value of wild, leafy plants
consumed by the Vhavenda. South Afric. J. Sci., 97: 51-54.
Ng, X. N., F. Y. Chye and A. M. Ismail (2012). Nutritional profile and antioxidative
properties of selected tropical wild vegetables. Int. Food Res. J., 19(4): 1487-
1496.
Niizu, P.Y. and D. B. Rodriguez-Amaya (2005). New data on the carotenoid composition
of raw salad vegetables. J. Food Comp. Anal., 18: 739-749.
Nkafamiya, I. I., S. A. Osemeahon, U. U. Modibbo and A. Aminu (2010). Nutritional
status of non-conventional leafy vegetables, Ficus asperifolia and Ficus
sycomorus. Afr. J. Food Sci., 4(3): 104-108.
Nwaogu, L. A., C. O. Ujowundu and A. I. Mgbemena (2000). Studies on the Nutritional
and Phytochemical Composition of Amaranthus hybridus leaves. Bio-Res.,
(4(1): 28-31.
O’Beirne, D. and G. A. Francis (2003). Reducing the pathogen risk in MAP-prepared
produce. In R. Ahvenainen (Ed.), Novel food packaging techniques.
Cambridge, UK; Boca Raton, FL: Woodhead Publishing Limited/CRC Press
LLC. pp: 231-286.
Obadoni, B.O. and P.O. Ochuko (2001). Phytochemical studies and comparative efficacy
of the crude extracts of some homeostatic plants in Edo and Delta State of
Nigeria. Global J. Pure Appl. Sci., 8: 203-208.
Odhav, B., S. Beerkrum, U. S. Akula and H. Baijnath (2007). Preliminary assessment of
nutritional value of traditional leafy vegetables in KwaZulu-Natal, South
Africa. J. Food Comp. Anal., 20(5): 430-435.
Odora-Hoppers, C. A. (2002). Indigenous knowledge and the integration of knowledge
systems: Towards a philosophy of articulation. Claremont: New Africa Books.
Odora-Hoppers, C. A. (2004). Culture, indigenous knowledge & development: The role
of University Occasional Paper no. 5. Braamfontein, Johannesburg: Centre for
Education Policy Development.
Offor, C. E., C. Aloke, P. C. U. Okechukwu, E. U. Ekpono, C. S. Nwobasi and E. E.
Egbeji (2017). Phytochemical and proximate compositions of Artocarpus
heterophyllus leaves. J. Appl. Sci., 2(1): 123-130.
Ogbede, S. C., A. N. Saidu, A. Y. Kabiru and M. B. Busari (2015). Nutrient and anti-
nutrient compositions of Brassica Oleracae Var. Capitata L. IOSR J. Pharm.,
5(3): 19-25.
Okerulu, I. O. and C. T. Onyema (2015). Comparative assessment of phytochemicals,
proximate and elemental composition of Gnetum africanum (Okazi) leaves.
Americ. J. Anal. Chem., 6: 604-609.
218
Okon, I. E. and U. S. James (2015). Comparative evaluation of nutritional values of
some wildplants leafy vegetables in South Eastern Nigeria. Int. J. Res. Appl.
Nat. Soc. Sci., 3(2): 21-26.
Okwu, D. E. and C. U. Ndu (2006). Evaluation of the phytonutrients, mineral and vitamin
contents of some varieties of yam. Int. J. Mol. Med. Adv. Sci., 2(2): 199-203.
Olaofe O. and C. O. Sanni (2007). Nutritional component of some non conventional leaf
vegetable consumed in Cameroon. Food Chem., 30: 73-77.
Olayemi, F.F., J. A. Adegbola, E. I. Bamishaiye and A. M. Daura (2010). Assessment of
post-harvest challenges of small scale farm holders of tomatoes, bell and hot
pepper in some local government areas of Kano State, Nigeria. Bayero J. Pure
Appl. Sci., 3: 39-42.
Olujobi, O. J. (2015). Evaluation of the nutritive composition of five indigenous tree
leaves used as vegetable in Ekiti State. J. Agric. Environ. Sci., 4(1): 185-197.
Oluyemi, E. A., A. A. Akinlua, A. A. Adenuga and M. B. Adebayo (2006). Mineral
contents of some commonly consumed Nigerian foods. Sci. Focus. 11: 153-
157.
Omale, J., A. R. Adeyemi and J. B. Omajali (2010). Phytoconstituents, proximate and
nutrient investigations of Saba florida (Benth.) from Ibaji forest. Int. J. Nut.
Metabolism., 2(5): 88-92.
Onunogbu, I. C. (2002). Lipids in human existence, 1st ed.; AP Express Publishing
Company: Nsukka, Nigeria.
Onwordi, C. T., A. M. Ogungbade and A. D. Wusu (2009). The proximate and mineral
composition of three leafy vegetables commonly consumed in Lagos, Nigeria.
Afr. J. Pure. Appl. Chem., 3(6): 102-107.
Onyeike, E. N., A. C. Ihugba and C. George (2003). Influence of heat processing on the
nutrient composition of vegetable leaves consumed in Nigeria. Plant foods
Hum. Nutr., 58:1-11.
Orech, F. O., J. Aagaard-Hansen and H. Friis (2007). Ethnoecology of traditional leafy
vegetables of the Luo people of Bondo district, Western Kenya. Int. J. Food
Sci. Nut., 58(7): 522-530.
Orhuamen, E. O., K. S. Olorunmaiye, A. C. Oreoluwa (2012). Proximate analysis of
fresh and dry leaves of Telfairia occidentalis (Hook.f.) and Talinum
triangulare (Jacq.) willd. Croatian J. Food Technol. Biotechnol. Nut., 7 (3-4):
188-191.
Orsat, V., V. Changrue, G. S. Vijaya Raghavan (2006). Microwave drying of fruits and
vegetables. Stewart Postharv. Rev., 6: 4- 9.
Osganian, S. K., M. J. Stampfer, E. Rimm, D. Spiegelman, F. B. Hu, J. E. Manson and
W. C. Willett (2003). Vitamin C and risk of coronary heart disease in women.
J. Americ. College Cardiol., 42(2): 246-252.
219
Oteng-Gang, K. and J. I. Mbachu (1990). Changes in the ascorbic acid content of some
tropical leafy vegetables during traditional cooing and local processing. J.
Food Chem., 23: 9-17.
Owolabi, A.O., U.S. Ndidi, B.D. James and F.A. Amune (2012). Proximate, antinutrient
and mineral composition of five varieties (improved and local) of Cowpea,
Vigna unguiculata, commonly consumed in Samaru community, Zaria-
Nigeria. Asian J. Food Sci. Technol., 4(2): 70-72.
Pandey, H. P. (2008). Economic Botany. Silver Line Publications 17/3 Mathura Road,
Faridabad U.P., India.
Pellegrini, N., E. Chiavaro, C. Gardana, T. Mazzeo, D. Contino, M. Gallo, P. Riso, V.
Fogliano and M. Porrini (2010). Effect of different cooking methods on color,
phytochemical concentration, and antioxidant capacity of raw and frozen
Brassica vegetables. J. Agric. Food Chem., 58: 4310-4321.
Pereira, C., L. Barros, A. M. Carvalho and C. F. R. Ferreira (2011). Nutritional
composition and bioactive properties of commonly consumed wild greens:
Potential sources for new trends in modern diets. Food Res. Int., 44: 2634-
2640.
Pieroni, A., L. Houlihan, N. Ansari, B. Husain and S. Astam (2007). Medicinal
perception of vegetable traditionally consumed by South-Asian migrants
living in Bradford, Northern England. J. Ethnopharm., 113: 100-110.
Pieroni, A., V. Janiak, C. M. Dr, S. Leke, E. Trachsel and M. Heinrich (2002). In vitro
antioxidant activity of non-cultivated vegetables of ethnic Albanians in
southern Italy. Phythother. Res., 16: 467-473.
Podsedek, A. (2007). Natural antioxidants and antioxidant activity of Brassica
vegetables: a review. LWT- Food Sci. Technol., 40: 1-11.
Puwastein, P., B. Burlingame, M. Raroeengwichit and P. Sungpuang (1999). ASEAN
Food Composition Tables. ASEAN Network of Food Data System
(ASEANFOODS): Institute of Nutrition, Mahidol University Thailand.
Qureshi, R. A., M. A. Ghufran, S. A. Gilani, Z. Yousaf, G. Abbas and A. Batool (2009b).
Indigenous medicinal plants used by local women in southern Himalayan
regions of Pakistan. Pak. J. Bot., 41: 19-25.
Qureshi, R., A. Waheed, M. Arshad and T. Umbreen (2009a). Medico-ethnobotanical
inventory of Tehsil Chakwal, Pakistan. Pak. J. Bot., 41(2): 529-538.
Qureshi, R. and G. R. Bhatti (2009). Folklore uses of Amaranthaceae family from Nara
desert, Pakistan. Pak. J. Bot., 41(4):1565-1572.
Qureshi, R.A., I. Ahmah and M. Ishtiaq (2006). Ethnobotany and phytosociological
studies of Tehsil Gugar Khan district Rawalpindi, Pakistan. Asian J. Plant
Sci., 5: 890-893.
220
Raghuvanshi, R.S. and R. Singh (2001). Nutritional composition of uncommon foods and
their role in meeting micronutrients needs. Int. J. Food Sci. Nut., 52(4): 331-
335.
Raven, P. H., R. F. Evert and S. E. Eichhorn (2005). In: photosynthesis, light, and life.
Biology of plants, seventh ed. W.H. Freeman, San Francisco, CA. 119-127.
Rehman, Z. U., M. Islam and W. H. Shah (2003). Effect of microwave and conventional
cooking on insoluble dietary fibre components of vegetables. Food Chem., 80:
237-240.
Renna, M. and M. Gonnella (2012). The use of the sea fennel as a new spice-colorant in
culinary preparations. Int. J. Gastro. Food Sci., 1: 111-115.
Riccardi M., G. Mele, C. Pulvento, A. Lavini, R. d'Andria and S. E. Jacobsen (2014).
Non-destructive evaluation of chlorophyll content in quinoa and amaranth
leaves by simple and multiple regression analysis of RGB image components.
Photosynth. Res., 120(3):263-72.
Richards, P. 1979. Community environmental knowledge in African rural development.
IDS Bull., 10(2): 28-32.
Ringeisen, B., D. M. Barrett and P. Stroeve (2013). Concentrated solar drying of
tomatoes. Energy Sustain. Dev., 19: 47-55.
Rivera, D., M. Heinrich, C. Obon and C. Inocencio (2006). Disseminating knowledge
about local food plants and local plant foods. Forum Nut., 59: 75-85.
Rocha, C. (2007). Food insecurity as market failure: A contribution from economics. J.
Hunger Environ. Nut., 1: 5-22.
Roe, M., S. Church, H. Pinchen and P. Finglas (2013). Nutrient analysis of fruit and
vegetables. Analytical Report, Institute of Food Research, Norwich Research
Park, Colney, Norwich.
Rojas, J., S. Avallone, P. Brat, G. Trystram and P. Bohuon (2006). The deep fat frying
process and their effect on acid ascorbic, carotenoids, potassium and colour on
plantain cylinders. J. Food Sci. Nut., 57: 123-136.
Rosegrant, M., S. Meijer and S. Cline (2008). International model for policy analysis of
agricultural commodities and trade (IMPACT): Model description. DC, USA:
International Food Policy Research Institute.
Rossi, M., C. Alamprese and S. Ratti (2007). Tocopherols and tocotrienols as free radical
scavengers in refined vegetable oils and their stability during deep-fat frying.
Food Chem., 102(3): 812-817.
Rouphael, Y., M. Cardarelli, A. Bassal, C. Leonardi, F. Giuffrida and G. Colla (2012).
Vegetable quality as affected by genetic, agronomic and environmental
factors. J. Food, Agric. Environ., 10: 680-688.
221
Rungapamestry, V., A. J. Duncan, Z. Fuller and B. Ratcliffe (2007). Effect of cooking
Brassica vegetables on the subsequent hydrolysis and metabolic fate of
glucosinolates. Proc. Nutri. Soc., 66(1): 69-81.
Rutto, L. K., Y. Xu, E. Ramirez M. Brandt (2013). Mineral properties and dietary value
of raw and processed Stinging Nettle (Urtica dioica). Int. J. Food Sci., 1-9.
SAC (2008). Fresh fruits and vegetables sampling. The Standardization Administration of
China: Beijing, China, pp: 1-8.
Saidu, A. N. and N. G. Jideobi (2009). The proximate and elemental analysis of some
leafy vegetables grown in Minna and Environs. J. Appl. Sci. Environ.
Manage., 13: 21-22.
Saikia, P. and D. C. Deka (2013). Mineral content of some wild green leafy vegetables of
North-East India. J. Chem. Pharm. Res., 5(3): 117-21.
Salazar, J., R. Velasquez, S. Quesada, L. A. Piccinelli and L. Rastrelli (2006). Chemical
composition and antinutritional factors of Lycianthes synanthera leaves
(chomte). Food Chem., 97:343-348.
Sanchez-Mata, M. C., R. D. Cabrera Loera, P. Morales, V. Fernandez-Ruiz, M. Camara,
C. Diez Marques, M. Pardo-de-Santayana, J. Tardio (2012). Wild vegetables
of the Mediterranean area as valuable sources of bioactive compounds. Gen.
Res. Crop Evol., 59: 431-443.
Satter, M. M. A., M. M. R. L. Khan, S. A. Jabin, N. Abedin, M. F. Islam, B. Shah (2016).
Nutritional quality and safety aspects of wild vegetables consume in
Bangladesh. Asian Pac. J. Trop. Biomed., 6(2): 125-131.
Saupi, N., M. H. Zakaria and J. S. Bujang (2009). Analytic chemical composition and
mineral content of yellow velvet leaf (Limnocharis flava L. Buchenau’s)
edible parts. J. Appl. Sci., 9: 2969-2974.
Saxena, R., K. Venkaiah, P. Anitha, L. Venu and M. Raghnath (2007). Antioxidant
activity of commonly consumed plant foods of India: contribution of their
phenolic content. Int. J. Food Sci. Nut., 58(4): 250-260.
Schunko, C. and C. R. Vogl (2010). Organic farmer’s use of wild food plants and fungi in
a hilly area in Styria (Austria). J. Ethnobiol. Ethnomed., 6: 1-14.
Schunko, C., S. Grasser and C. R. Vogl (2012). Intracultural variation of knowledge
about wild plant uses in the Biosphere Reserve Grosses Walsertal (Austria). J.
Ethnobiol. Ethnomed., 8: 1-11.
Seal, T., B. Pillai and K. Chaudhuri (2017). Evaluation of nutritional potential of five
unexplored wild edible plants consumed by the tribal people of Arunachal
Pradesh State in India. J. Food Nutr. Res., 5(1): 1-5.
Seal, T. and K. Chaudhury (2015). Ethnobotanical importance and nutritional potential of
wild leafy vegetables of Meghalaya state in India. Int. J. Appl. Biol. Pharm.
Technol., 6(1): 80-85.
222
Seema, A. (2015). Medicinal properties of wild leafy vegetables available in maharashtra
state in rainy season. Int. J. Recent Sci. Res., 6(8): 5875-5879.
Shad, A. A., H. U. Shah and J. Bakht (2013). Ethnobotanical assessment and nutritive
potential of wild food plants. J. Anim. Plant Sci., 23(1): 92-97.
Shah, M. T., S. Begun and S. Khan (2009). Pedo and Biogeochemical Studies of mafic
and intramafic rocks in the Mingora and Kabal areas, Swat, Pakistan. Environ.
Earth Sci., 60(5): 1091-1102.
Shakirin, F.H., K. N. Prasad, A. Ismail, L. C. Yuon and A. Azlan (2010). Antioxidant
capacity of underutilised Malaysian Canarium odontophyllum (dabai) Miq.
fruit. J. Food Comp. Anal., 23: 777-781.
Sheikh, S. A. and S. Javed (2007). Exploring the economic value of underutilized plant
species in ayubia national park. Pak. J. Bot., 39(5): 1435-1442.
Sher, H., A. Aldosari, A. Ali and H. J. deBoer (2014). Economic benefits of high value
medicinal plants to Pakistani communities: an analysis of current practice and
potential. J. Ethnobiol. Ethnomed., 10: 1-16.
Sher, H., A. Aldosari, A. Ali and H. J. deBoer (2015). Indigenous knowledge of folk
medicines among tribal minorities in Khyber Pakhtunkhwa, North Western
Pakistan. J. Ethnopharmacol., 166: 157-167.
Sher, H., M. Al-Yemeni and H. Sher (2010). Forest resource utilization assessment for
economic development of rural community in northern parts of Pakistan. J.
Med. Plants Res., 4: 1786-1789.
Shinwari, Z. K. (2010). Medicinal plants research in Pakistan. J. Med. Plants Res., 4(3):
161-176.
Shukla, Y. N., S. Dubey, S. P. Jain and S. Kumar (2001). Chemistry, biology and uses of
Adansonia digitate: a review. J. Med. Arom. Plant Sci., 23: 429-434.
Shumsky, S., G. M. Hickey, T. Johns, B. Pelletier and J. Galaty (2014). Institutional
factors affecting wild edible plant (WEP) harvest and consumption in semi-
arid Kenya. Land Use Pol., 38: 48-69.
Sidhu, K., J. Kaur, G. Kaur and K. Pannu (2007). Prevention and cure of digestive
disorders through the use of medicinal plants. J. Hum. Ecol., 21(2): 113-116.
Sidibe, M. and J. T. Williams (2002). Baobab. Adansonia digitata. (Southampton, United
Kingdom: International Centre for Underutilised Crops), pp: 14-16.
Silva, E. M., J. N. S. Souza, H. Rogez, J. F. Rees and Y. Larondelle (2007). Antioxidant
activities and polyphenolic contents of fifteen selected plant species from the
Amazonian region. Food Chem., 101(3): 1012-1018.
Singh, J., A. K. Upadhyay, K. Prasad, A. Bahadur and M. Rai (2007). Variability of
carotenes, vitamin C, E and phenolics in Brassica vegetables. J. Food Comp.
Anal., 20: 106-112.
223
Sivasubramanian, R., and Brindha, P. (2013). In-vitro cytotoxic, antioxidant and GC-MS
studies on Centratherum punctatum cass. Int. J. Pharm. Pharm.Sci. 5, 3–6.
Sletto, R. F. (1937). A construction of personality scales by the criterion of interval
consistency. Sociological Press, Hanover.
Sobowale, S. S., O. P. Olatidoje, O. O. Olorode and J. V. Akinlotan (2011). Nutritional
potentials and chemical value of some tropical leafy vegetables consumed in
South West Nigeria. J. Sci. Multidiscipl. Res., 3: 55-61.
Sotelo, A., S. Lopez-Garcia, F. Basurto-Pena (2007). Content of nutrient and antinutrient
in edible flowers of wild plants in Mexico. Plant Foods Hum. Nutr., 62(3):
133-138.
Srilakshmi, B. (1996). Food Science. 2nd Ed., New Age International (P) Ltd. Publishers,
New Delhi.
Stagos, D., G. D. Amoutzias, A. Matakos, A. Spyrou, A. M. Tsatsakis and D. Kouretas
(2012). Chemoprevention of liver cancer by plant polyphenols. Food Chem.
Toxicol., 50: 2155-2170.
Stamp, P., R. Messmer, A. Walter (2012). Competitive underutilized crops will depend
on the state funding of breeding programmes: An opinion on the example of
Europe. Plant Breed., 131: 461-464.
Stanacev, V., D. Dukic, S. Kovcin, M. Drinic, N. Puvaca and V. Stanacev (2010)
Nutritive Value of the Genetically Divergent Genotypes of Lucerne
(Medicago sativa L.). Afric. J. Agric. Res., 5: 1284-1287.
Steel, R. G. D. and J. H. Torrie (1980). Principles and procedures of statistics. 2nd ed.
New York: McGraw-Hill.
Subhasree, B., R. Baskar, K. R. Laxmi, S. R. Lijina and P. Rajasekaran (2009).
Evaluation of antioxidant potential in selected green leafy vegetables. Bio.
Res. Technol., 100(2): 186-194.
Taleni, V., P. Nyoni and N. Goduka (2012). People's perceptions on indigenous leafy
vegetables: A case study of Mantusini Location of the Port St Johns Local
Municipality, in the Eastern Cape, South Africa. Strategies to overcome
poverty and inequality: Towards Carnegie III (pp. 1–16). Cape Town:
University of Cape Town.
Tardio, J. (2010). Spring is coming: the gathering and consumption of wild vegetables in
Spain. In: Pardo-de-Santayana, M., Pieroni, A., Puri, R. (Eds.), Ethnobotany
in the New Europe: People, Health and Wild Plant Resources. Berghahn
Books, Oxford, New York. pp: 211-238.
Tardio, J., M. Molina, L. Aceituno-Mata, M. Pardo-de-Santayana, R. Morales, V.
Fernandez-Ruiz, P. Morales, P. Garcia, M. Camara and M. C. Sanchez-Mata
(2011). Montia fontana L. (Portulacaceae), an interesting wild vegetable
224
tradi-tionally consumed in the Iberian Peninsula. Gen. Res. Crop Evol., 58:
1105-1118.
Tarkergari, S., K. Waghray and S. Gulla (2013). Acceptability studies of value added
products with Purslane (Portulaca oleracea). Pak. J. Nut., 12(1): 93-96.
Thaifoods (2002). Methods of food analysis. Thailand.
Tilman, D., P. B. Reich and J. M. H. Knops (2006). Biodiversity and ecosystem stability
in a decade-long grassland experiment. Nat., 441: 629-632.
Tope, O. D., O. O. Emmanuel, O. A. Adebayo and O. V. Tosin (2017). Phytochemical
constituents, proximate composition and mineral analysis of aqueous and
ethanolic stem bark, seed extracts and plant parts of Moringa oleifera. J. Appl.
Life Sci. Int., 10(4): 1-7.
Trowbridge, F. and M. Martorell (2002). Forging effective strategies to combat iron
deficiency. Summary and recommendations. J. Nutr., 132: 875-879.
Tuli, R. T., M. M. Rahman, A. T. Abdullah, M. Akhtauzzaman and S. N. Islam (2017).
Phytochemicals - tannins in some leafy vegetables of Bangladesh. Ind. J.
Nutr., 3(2): 1- 2.
Tuncturk, M. and F. Ozgokce (2015). Chemical composition of some Apiaceae plants
commonly used in herby cheese in Eastern Anatolia. Turk. J. Agric. For., 39:
55-62.
Turan, M., S. Kordali, H. Zengin, A. Dursun and Y. Sezen (2003). Macro and micro
mineral content of some wild edible leaves consumed in Eastern Anatolia.
Acta Agr. Scand. B., 53: 129-137.
Turkmen, N., F. Sari and Y. S. Velioglu (2005). The effect of cooking methods on total
phenolics and antioxidant activity of selected green vegetables. Food Chem.,
93: 713-718.
Turner, N. J., L. J. Luczaj, P. Migliorini, A. Pieroni, A. L. Dreon, L. E. Sacchetti and M.
G. Paoletti (2011). Edible and tended wild plants, traditional ecological
knowledge and agroecology. Critic. Rev. Plant Sciences., 30: 198-225.
Ullah, S., M. R. Khan, A. S. Shah, S. A. Shah, M. Majid, M. A. Farooq (2014).
Ethnomedicinal plant use value in the Lakki Marwat district of Pakistan. J.
Ethnopharmacol., 158: 412-422.
Umar, K. J., L. G. Hassan, S. M. Dangoggo and M. Ladan (2007). Nutritional
composition of water spinach (Ipomoea aquatic forsk) leaves. J. Appl. Sci.,
7(6): 803-809.
Umuhozariho, M. G., N. B. Shayo, P. Y. K. Sallah and J. M. Msuya (2013). Sensory
evaluation of different preparations of cassava leaves from three species as a
leafy vegetable. Afric. J. Biotechnol., 12(46): 6452-6459.
225
Uusiku, N. P., A. Oelofse, K. G. Duodu, M. J. Bester and M. Faber (2010). Nutritional
value of leafy vegetables of sub-Saharan Africa and their potential
contribution to human health: A review. J. Food Compos. Anal., 23(6): 499-
509.
Uusiku, N.P., A. Oelofse, K. G. Duodu, M. J. Bester, M. Faber (2010). Nutritional value
of leafy vegetables of sub-Saharan Africa and their potential contribution to
human health: a review. J. Food Compos. Anal., 23: 499-509.
Vadivel, V. and K. Janardhanan (2005). Nutritional and antinutritional characteristicsof
seven South Indian wild legumes. Plant Foods Hum. Nutr., 60(2): 69-75.
Vaid, B. (2008). A study on nutrient profile and sensory characteristics of foods cooked
by conventional methods, microwave cooking and solar cooking. Doctor of
philosophy in home science. Amt. S.B. Gardi Institute of Home Science
Saurashtra University, Rajkot, Gujarat.
Valdes, A.F. and A. B. Garcia (2006). A study of the evolution of the physicochemical
and structural characteristics of olive and sunflower oils after heating at frying
temperatures. Food Chem., 98(2): 214-219.
Van-derWalt, A. M., D. T. Loots, M. I. M. Ibrahim and C. C. Bezuldenhout (2009).
Minerals, trace elements and antioxidant phytochemicals in wild African dark-
green leafy vegetables (morogo). South Afric. J. Sci., 105: 444-448.
Van-Rensburg, W. S. J., W. Van-Averbeke, R. Slabbert, M. Faber, P. J. Van-Jaarsveld, I.
Van-Heerden, F. Wenhold and A. Oelofse (2007). African leafy vegetables in
South Africa. Water SA, 33(3): 317-326.
Van-Vuuren, L. (2006). Wild vegetables: Tamed to decrease hunger: Emerging
Agriculture. The Water Wheel, 5: 22-25.
Varoquaux, P. and R. Wiley (1994). Biological and biochemical changes in minimally
processed refrigerated fruits and vegetables. In R. C. Wiley (Ed.), Minimally
processed refrigerated fruits and vegetables (pp. 226e268). New York, USA:
Chapman and Hall.
Venter, S. L., W. S. Jansen van Rensburg, H. J. Vorster, E. Van-den-Heever J. J. B. Van-
Zijl (2007). Promotion of African leafy vegetables within the agricultural
research council vegetable and ornamental plant institute: the impact of the
project. Afric. J. Food Agric. Nut. Develop., 7(4): 1-7.
Viljoen, A. T., P. Botha and C. C. Boonzaaier (2005). Factors contributing to changes in
food practices of a black South African community. J. Family Ecol. Consum.
Sci., 33: 46-62.
Visioli, F., C. A. De-La-Lastra, C. Andres-Lacueva, M. Aviram, C. Calhau, A. Cassano,
M. D’Archivio, A. Faria, G. Fave, V. Fogliano, R. Llorach, P. Vitaglione, M.
Zoratti, M. Edeas (2011). Polyphenols and human health: a prospectus. Crit.
Rev. Food Sci. Nutr., 51: 524-546.
226
Visioli, F., S. Grande, P. Bogani and C. Galli (2004). The role of antioxidants in the
Mediterranean diets: focus on cancer. Eur. J. Cancer Prev., 13: 337-343.
Volden, J., G. I. A. Borge, M. Hansen, T. Wicklund and G. B. Bengtsson (2009).
Processing (blanching, boiling, steaming) effects on the content of
glucosinolates and antioxidant-related parameters in cauliflower (Brassica
oleracea L. ssp. botrytis). LWT- Food Sci. Technol., 42: 63-73.
Vorster, I. H. J., W. Jansen-van-Rensburg, J. J. B. Van-Zijl and L. S. Venter (2007). The
importance of traditional leafy vegetables in South Africa. Afric. J. Food,
Agric. Nut. Develop., 7(4): 1-13.
Vunchi, M. A., A. N. Umar, M. A. King, A. A. Liman, G. Jeremiah and C. O. Aigbe
(2011). Proximate vitamins and minerals composition of virtex donianna
(black plum) fruit pulp Nig. J. Basic and Appl. Sci., 19(1): 97-101.
Ward C. M. and V. C. Trenerry (1997). The determination of niacin in cereals, meat and
selected foods by capillary electrophoresis and high performance liquid
chromatography. Food Chem., 60: 667-674.
Ward, J. A., N. L. Dawkins, J. Shikany and R. D. Pace (2009). Boost for Purslane. The
world of food ingredients. pp: 58-60.
Watchtel-Galor, S., K. W. Wong and I. F. F. Benzie (2008). The effect of cooking on
Brassica vegetables. Food Chem. 110: 706-710.
WHO/FAO (2003). Diet, nutrition and prevention of chronic diseases. Report of a Joint
WHO/FAO expert consultation (Geneva).
Wootton-Beard, P. C. and L. Ryan (2011). Improving public health: The role of
antioxidant-rich fruit and vegetable beverages. Food Res. Int., 44: 3135-3148.
Wu, M., C. Hou, C. Jiang, Y. Wang, C. Wang, H. Chen and H. Chang (2007). A novel
approach of LED light radiation improves the antioxidant activity of pea
seedlings. Food Chem., 101: 1753-1758.
Yadav, S. K. and S. Sehgal (2003). Effect of domestic processing and cooking on
selected antinutrient contents of some green leafy vegetables. Plant Food
Hum. Nutr., 58: 1-11.
Yahia, E. M. (2010). The contribution of fruit and vegetable consumption to human
health. In: De la Rosa, L.A., Alvarez-Parrilla, E., González-Aguilar, G.A.
(Eds.), Fruit and Vegetable Phytochemicals: Chemistry, Nutritional Value and
Stability. Wiley- Blackwell, New Delhi, India, pp: 3-51.
Yao, J., B. Yan, X. Q. Wang and J. X. Liu (2000). Nutritional evaluation of mulberry
leaves as feeds for ruminants. Livest. Res. Rural Develop., 12: 9-16.
Yirankinyuki, F. F., W. L. Danbature, M. M. Muzakir and S. Y. Simon (2015). Chemical
composition and nutritive value of leptadenia hastata leaves. Int. J. Innov.
Sci. Res., 4(10): 480-484.
227
Zahran, M. A. and Y. A. El-Amier (2013). Non-Traditional Fodders from the Halophytic
Vegetation of the deltaic Mediterranean Coastal Desert, Egypt. J. Bio. Sci.,
13: 226-233.
Zhang, D. and Y. Hamauzu (2004). Phenolics, ascorbic acid, carotenoids and antioxidant
activity of broccoli and their changes during conventional and microwave
cooking. Food Chem., 88: 503-509.
Zhang, J., W. Han, L. Huang, Z. Zhang, Y. Ma and Y. Hu (2016). Leaf chlorophyll
content estimation ofwinter wheat based on visible and near-infrared sensors.
Sensors, 16 (437): 1-11.
Zhang, M., J. Tang, A. S. Mujumdar and S. Wang (2006). Trends in microwave-related
drying of fruits and vegetables. Trends Food Sci. Technol., 17 (10): 524- 534.
228
APPENDICES
Appendix I. Best of fit curve of minerals standards (Calcium, Copper, Iron,
Zinc, Manganese, Magnesium, Sodium and potassium)
229
230
Appendix II. Best of fit curve of vitamin standards (vitamin A (β-carotene),
vitamin C (Ascorbic acid), vitamin B1 (Thiamine), vitamin B2
(Ribofilavin) and vitamin B3 (Niacin))
231
Appendix III. Best of fit curve of chromatograms of vitamin standards
(vitamin B1 (Thiamine), vitamin B2 (Ribofilavin), vitamin B3
(Niacin), vitamin A (β-carotene) and vitamin C (Ascorbic acid)
232
233
234
Appendix IV. Best of fit curve of phytochemical standards (total flavonoids,
total phenols and total tanins)
235
Appendix V. Analysis of variance for moisture content of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 2 1.1
Vegetable 4 320 80.1 38.68 0.000
Processing 4 99998 24999.5 12071.7 0.000
Vegetable × Processing 16 261 16.3 7.89 0.000
Error 48 99 2.1
Total 74 100682
CV 2.83
Appendix VI. Analysis of variance for ash content of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 0.10 0.050
Vegetable 4 131.21 30.303 498.77 0.00
Processing 4 1322.50 330.624 5441.88 0.00
Vegetable × Processing 16 114.31 7.144 117.59 0.00
Error 48 2.92 0.061
Total 74 1561.03
CV 4.55
Appendix VII. Analysis of variance for protein content of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 0.029 0.0146
Vegetable 4 99.771 24.9426 243.79 0.000
Processing 4 59.540 14.8851 145.49 0.000
Vegetable × Processing 16 3.829 0.2393 2.34 0.012
Error 48 4.911 0.1023
Total 74 168.081
CV 7.64
Appendix VIII. Analysis of variance for fat content of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 0.0533 0.02663
Vegetable 4 13.8945 3.47364 23.40 0.000
Processing 4 31.9105 7.97764 53.74 0.000
Vegetable × Processing 16 07838 0.04899 0.33 0.990
Error 48 7.1251 0.14844
Total 74 53.7673
CV 17.33
236
Appendix IX. Analysis of variance for fiber content of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 2.55 1.277
Vegetable 4 19.31 4.827 7.10 0.000
Processing 4 1111.92 277.980 408.68 0.000
Vegetable × Processing 16 21.25 1.328 1.95 0.037
Error 48 32.65 0.680
Total 74 1187.68
CV 14.23
Appendix X. Analysis of variance for carbohydrate content of various vegetables
and processing methods
Source DF SS MS F P
Rep 2 11.9 6.0
Vegetable 4 454.0 113.5 10.67 0.000
Processing 4 57105.5 14276.4 1342.33 0.000
Vegetable × Processing 16 202.1 12.6 1.19 0.311
Error 48 510.5 10.6
Total 74 58284.0
CV 10.36
Appendix XI. Analysis of variance for acetic acid of various vegetables and
processing methods Source DF SS MS F P
Rep 2 0.00049 0.00024
Vegetable 4 0.00934 0.00234 24.84 0.00
Processing 4 0.15307 0.03827 407.11 0.00
Vegetable × Processing 16 0.00219 0.00014 1.46 0.156
Error 48 0.00451 0.00009
Total 74 0.16961
CV 15.74
Appendix XII. Analysis of variance for citric acid of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 0.00022 0.00011
Vegetable 4 0.03441 0.00860 82.98 0.000
Processing 4 0.31439 0.07860 758.19 0.000
Vegetable × Processing 16 0.01949 0.00122 11.75 0.000
Error 48 0.00498 0.00010
Total 74 0.37349
CV 12.79
237
Appendix XIII. Analysis of variance for oxalic acid of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 0.00011 0.00006
Vegetable 4 0.00867 0.00217 44.26 0.000
Processing 4 0.04774 0.01194 243.58 0.000
Vegetable × Processing 16 0.00511 0.00032 6.52 0.000
Error 48 0.00235 0.00005
Total 74 0.06399
CV 17.62
Appendix XIV. Analysis of variance for tartaric acid of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 0.00027 0.00014
Vegetable 4 0.05706 0.01427 81.48 0.000
Processing 4 0.40432 0.10108 577.30 0.000
Vegetable × Processing 16 0.02208 0.00138 7.88 0.000
Error 48 0.00840 0.00018
Total 74 0.49215
CV 15.18
Appendix XV. Analysis of variance for copper content of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 0.0119 0.00594
Vegetable 4 17.0266 4.25666 347.88 0.000
Processing 4 16.9338 4.23344 345.98 0.000
Vegetable × Processing 16 6.0126 0.37579 30.71 0.000
Error 48 0.5873 0.01224
Total 74 40.5723
CV 7.50
Appendix XVI. Analysis of variance for iron content of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 0.132 0.0659
Vegetable 4 114.221 28.5553 1164.12 0.000
Processing 4 9.508 2.3770 96.91 0.000
Vegetable × Processing 16 3.087 0.1929 7.87 0.000
Error 48 1.177 0.0245
Total 74 128.125
CV 6.50
238
Appendix XVII. Analysis of variance for zinc content of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 0.072 0.0362
Vegetable 4 42.949 10.7373 522.16 0.000
Processing 4 194.862 48.7155 2369.03 0.000
Vegetable × Processing 16 3.509 0.2193 10.67 0.000
Error 48 0.987 0.0206
Total 74 242.380
CV 3.76
Appendix XVIII. Analysis of variance for manganese content of various vegetables
and processing methods
Source DF SS MS F P
Rep 2 0.01277 0.00639
Vegetable 4 6.00147 1.50037 218.22 0.000
Processing 4 1.89459 0.47365 68.89 0.000
Vegetable × Processing 16 0.28665 0.01792 2.61 0.005
Error 48 0.33003 0.00688
Total 74 8.52551
CV 7.55
Appendix XIX. Analysis of variance for calcium content of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 4 0.00011
Vegetable 4 600797 0.00860 82.98 0.000
Processing 4 550279 0.07860 758.19 0.000
Vegetable × Processing 16 0.01949 0.00122 11.75 0.000
Error 48 0.00498 0.00010
Total 74 0.37349
CV 0.68
Appendix XX. Analysis of variance for magnesium content of various vegetables
and processing methods
Source DF SS MS F P
Rep 2 0.2 0.11
Vegetable 4 22653.1 5663.28 156628 0.000
Processing 4 24029.5 6007.37 166145 0.000
Vegetable × Processing 16 1272.7 79.54 2199.84 0.000
Error 48 1.7 0.04
Total 74 47957.2
CV 0.33
239
Appendix XXI. Analysis of variance for sodium content of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 1 0.36629
Vegetable 4 204964 51240.9 1589327 0.000
Processing 4 6522075 1630519 5.1E+07 0.000
Vegetable × Processing 16 25645 1602.79 49713.4 0.000
Error 48 2 0.03224
Total 74 6752685
CV 0.02
Appendix XXII. Analysis of variance for potassium content of various vegetables
and processing methods
Source DF SS MS F P
Rep 2 0.02981 0.01491
Vegetable 4 34677.3 8669.33 627591 0.000
Processing 4 1139705 284926 2.1E+07 0.000
Vegetable × Processing 16 3537.74 221.109 16006.5 0.000
Error 48 0.66306 0.01381
Total 74 1177920
CV 0.01
Appendix XXIII. Analysis of variance for alkaloids of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 0.0030 0.0015
Vegetable 4 83.146 20.786 18533.3 0.00
Processing 4 1.9670 0.4917 438.45 0.00
Vegetable × Processing 16 1.2150 0.0759 67.71 0.00
Error 48 0.0538 0.0011
Total 74 86.385
CV 3.74
Appendix XXIV. Analysis of variance for saponins of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 0.0003 0.0001
Vegetable 4 73.2142 18.3036 13943.8 0.000
Processing 4 6.9445 1.7361 1322.59 0.000
Vegetable × Processing 16 4.2469 0.2654 202.21 0.000
Error 48 0.0630 0.0013
Total 74 84.4689
CV 2.57
240
Appendix XXV. Analysis of variance for flavinoids of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 0.0004 0.00018
Vegetable 4 11.1299 2.78248 75089.5 0.000
Processing 4 2.6877 0.67192 18132.7 0.000
Vegetable × Processing 16 0.7459 0.04662 1258.13 0.000
Error 48 0.0018 0.00004
Total 74 14.5657
CV 0.86
Appendix XXVI. Analysis of variance for phenol of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 0.001 0.0003
Vegetable 4 229.610 57.4024 664893 0.000
Processing 4 12.314 3.0784 35657.7 0.000
Vegetable × Processing 16 8.396 0.5248 6078.46 0.000
Error 48 0.004 0.0001
Total 74 250.324
CV 0.44
Appendix XXVII. Analysis of variance for tanins of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 0.00112 0.00056
Vegetable 4 0.56007 0.14002 477.43 0.000
Processing 4 0.57245 0.14311 487.97 0.000
Vegetable × Processing 16 0.18843 0.01178 40.16 0.000
Error 48 0.01408 0.00029
Total 74 1.33615
CV 8.88
Appendix XXVIII. Analysis of variance for vitamin A of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 0.017 0.0086
Vegetable 4 97.278 24.3194 1764.41 0.000
Processing 4 29.479 7.3697 534.68 0.000
Vegetable × Processing 16 14.760 0.9225 66.93 0.000
Error 48 0.662 0.0138
Total 74 142.195
CV 6.98
241
Appendix XXIX. Analysis of variance for vitamin C of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 3.920E-04 1.960E-04
Vegetable 4 11266.9 2816.73 1.1E+07 0.000
Processing 4 6298.58 1574.64 6437338 0.000
Vegetable × Processing 16 1152.90 72.0562 294575 0.000
Error 48 0.01174 2.446E-04
Total 74 18718.4
CV 0.06
Appendix XXX. Analysis of variance for vitamin B1 of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 0.00064 0.00032
Vegetable 4 0.19993 0.04998 182.34 0.000
Processing 4 0.04618 0.01154 42.12 0.000
Vegetable × Processing 16 0.02531 0.00158 5.77 0.000
Error 48 0.01316 0.00027
Total 74 0.28522
CV 19.68
Appendix XXXI. Analysis of variance for vitamin B2 of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 0.00211 0.00106
Vegetable 4 0.81569 0.20392 694.93 0.000
Processing 4 0.07734 0.01934 65.89 0.000
Vegetable × Processing 16 0.05141 0.00321 10.95 0.000
Error 48 0.01409 0.00029
Total 74 0.96063
CV 13.08
Appendix XXXII. Analysis of variance for vitamin B3 of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 0.00211 0.00106
Vegetable 4 0.81569 0.20392 694.93 0.000
Processing 4 0.07734 0.01934 65.89 0.000
Vegetable × Processing 16 0.05141 0.00321 10.95 0.000
Error 48 0.01409 0.00029
Total 74 0.96063
CV 14.79
242
Appendix XXXIII. Analysis of variance for total solids of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 2 1.1
Vegetable 4 320 80.1 38.68 0.000
Processing 4 99998 24999.5 12071.7 0.000
Vegetable × Processing 16 261 16.3 7.89 0.000
Error 48 99 2.1
Total 74 100682
CV 2.93
Appendix XXXIV. Analysis of variance for total soluble solids of various vegetables
and processing methods
Source DF SS MS F P
Rep 2 0.0021 0.00105
Vegetable 4 15.1587 3.78966 1790.96 0.000
Processing 4 15.6643 3.91607 1850.69 0.000
Vegetable × Processing 16 0.9410 0.05881 27.79 0.000
Error 48 0.1016 0.00212
Total 74 31.8676
CV 3.09
Appendix XXXV. Analysis of variance for energy value of various vegetables and
processing methods
Source DF SS MS F P
Rep 2 197 98
Vegetable 4 3129 782 5.29 0.001
Processing 4 774551 193638 1310.25 0.000
Vegetable × Processing 16 2351 147 0.99 0.478
Error 48 7094 148
Total 74 787322
CV 8.61
Appendix XXXVI. Analysis of variance for pH of various vegetables and processing
methods
Source DF SS MS F P
Rep 2 0.00948 0.00474
Vegetable 4 3.35484 0.83871 323.66 0.000
Processing 4 1.39460 0.34865 134.54 0.000
Vegetable × Processing 16 0.10076 0.00630 2.43 0.009
Error 48 0.12438 0.00259
Total 74 4.98407
CV 0.72
243
Appendix XXXVII. Analysis of variance for nitrogen free extract of various
vegetables and processing methods
Source DF SS MS F P
Rep 2 69.6 34.8
Vegetable 4 594.9 148.7 4.03 0.006
Processing 4 42355.4 10588.8 286.65 0.000
Vegetable × Processing 16 258.3 16.1 0.44 0.963
Error 48 1773.1 36.9
Total 74 45051.3
CV 23.67
Appendix XXXVIII. Analysis of variance for total fatty acids of various vegetables
and processing methods
Source DF SS MS F P
Rep 2 0.0004 0.00018
Vegetable 4 11.1299 2.78248 75089.5 0.000
Processing 4 2.6877 0.67192 18132.7 0.000
Vegetable × Processing 16 0.7459 0.04662 1258.13 0.000
Error 48 0.0018 0.00004
Total 74 14.5657
CV 17.25
Appendix XXXIX. Analysis of variance for total chlorophyll of various vegetables
Source DF SS MS F P
Rep 2 0.0001 0.00005
Vegetable 4 15.2128 3.80319 107477 0.000
Error 8 0.0003 0.00004
Total 14 15.2131
CV 0.35
244
Appendix XL. Correlation matrix (r) of quality parameters of different vegetables under the influence of processing
treatments
MC TS A PH TSS CF F FA Pro CH NFE E AA CA OA TA Cu Fe Zn Mn Ca Mg Na K Alk Sap Fla Phe Tan VA VC VB1 VB2 VB3
MC 1
TS -0.95 1
A -0.90 0.91 1
PH 0.24 -0.24 -0.04 1
TSS -0.63 0.63 0.67 -0.19 1
CF -0.87 0.87 0.79 -0.27 0.63 1
F -0.11 0.11 0.01 -0.49 0.14 0.03 1
FA 0.02 -0.01 -0.10 -0.11 -0.04 -0.06 0.78 1
Pro -0.31 0.31 0.21 -0.27 0.25 0.24 0.47 0.35 1
CH -0.99 0.99 0.87 -0.23 0.59 0.83 0.06 -0.05 0.26 1
NFE -0.98 0.98 0.85 -0.21 0.56 0.78 0.06 -0.04 0.25 0.99 1
E -0.99 0.99 0.85 -0.29 0.60 0.83 0.18 0.04 0.34 0.99 0.98 1
AA -0.92 0.92 0.84 -0.14 0.57 0.76 0.01 -0.11 0.22 0.92 0.92 0.91 1
CA -0.92 0.92 0.84 -0.14 0.57 0.76 0.01 -0.11 0.22 0.92 0.92 0.91 0.97 1
OA -0.92 0.92 0.84 -0.14 0.57 0.76 0.01 -0.11 0.22 0.92 0.92 0.91 0.98 0.95 1
TA -0.92 0.92 0.84 -0.14 0.57 0.76 0.01 -0.11 0.22 0.92 0.92 0.91 0.96 0.97 0.98 1
Cu -0.67 0.67 0.73 0.17 0.42 0.55 0.06 0.09 -0.09 0.66 0.66 0.65 0.67 0.67 0.67 0.67 1
Fe -0.68 0.68 0.82 0.11 0.48 0.60 0.02 0.01 -0.12 0.66 0.65 0.65 0.67 0.67 0.67 0.67 0.92 1
Zn -0.79 0.79 0.9 0.06 0.61 0.68 0.16 0.11 0.31 0.75 0.74 0.76 0.74 0.74 0.74 0.74 0.81 0.86 1
Mn -0.68 0.68 0.81 0.10 0.47 0.61 0.05 0.05 -0.07 0.65 0.64 0.64 0.65 0.65 0.65 0.65 0.92 0.99 0.87 1
Ca -0.81 0.81 0.76 -0.17 0.46 0.74 0.07 0.03 0.09 0.81 0.79 0.80 0.72 0.72 0.72 0.72 0.83 0.82 0.77 0.85 1
Mg -0.43 0.43 0.67 -0.02 0.43 0.46 0.01 -0.09 0.19 0.37 0.34 0.37 0.35 0.35 0.35 0.35 0.31 0.61 0.68 0.61 0.41 1
Na -0.97 0.97 0.87 -0.17 0.61 0.83 0.18 0.06 0.27 0.96 0.96 0.97 0.91 0.91 0.91 0.91 0.75 0.73 0.81 0.72 0.82 0.36 1
K -0.94 0.94 0.85 -0.14 0.53 0.78 0.18 0.09 0.27 0.94 0.94 0.95 0.92 0.92 0.92 0.92 0.77 0.75 0.81 0.75 0.83 0.37 0.97 1
Alk -0.01 0.01 0.31 0.35 0.21 0.04 -0.13 -0.17 0.01 -0.03 -0.05 -0.05 -0.03 -0.03 -0.03 -0.03 0.18 0.39 0.45 0.40 0.09 0.74 -0.02 -0.02 1
Sap -0.08 0.08 0.01 0.11 0.01 0.06 -0.09 0.04 0.48 0.07 0.07 0.07 -0.03 -0.03 -0.03 -0.03 0.06 -0.11 0.15 -0.03 0.21 -0.14 0.05 0.03 0.07 1
Fla -0.06 0.06 0.03 0.16 0.03 0.04 -0.17 -0.06 0.46 0.05 0.05 0.04 -0.04 -0.04 -0.04 -0.04 0.02 -0.12 0.14 -0.05 0.14 -0.08 0.01 0.00 0.14 0.97 1
Phe -0.08 0.01 -0.09 -0.03 -0.07 0.05 -0.01 0.08 0.52 0.09 0.09 0.11 -0.01 -0.01 -0.01 -0.01 -0.05 -0.31 -0.02 -0.23 0.10 -0.40 0.06 0.03 -0.30 0.91 0.87 1
Tan -0.09 0.09 0.34 0.45 0.29 0.08 -0.34 -0.31 -0.15 0.07 0.07 0.03 0.07 0.07 0.07 0.07 0.44 0.44 0.39 0.46 0.27 0.28 0.07 0.08 0.58 0.34 0.43 0.07 1
VA 0.06 -0.06 0.00 0.19 0.21 -0.05 -0.25 -0.18 -0.55 -0.03 -0.03 -0.08 0.09 0.09 0.09 0.09 0.31 0.21 -0.03 0.20 0.09 -0.26 -0.02 0.02 -0.16 -0.22 -0.21 -0.22 0.38 1
VC 0.03 -0.03 0.19 0.52 0.37 -0.08 -0.18 -0.22 0.16 -0.06 -0.05 -0.07 0.01 0.01 0.01 0.01 0.09 0.05 0.25 0.04 -0.19 0.13 -0.01 -0.04 0.51 0.28 0.39 0.12 0.61 0.12 1
VB1 -0.01 0.01 -0.08 0.20 0.11 -0.05 -0.11 -0.03 0.30 0.01 0.03 0.01 0.02 0.02 0.02 0.02 -0.06 -0.32 -0.09 -0.31 -0.17 -0.51 0.02 -0.01 -0.35 0.54 0.56 0.69 0.11 0.13 0.50 1
VB2 -0.01 0.00 -0.11 0.05 -0.07 -0.01 -0.11 0.06 -0.11 0.03 0.03 0.01 0.01 0.01 0.01 0.01 0.32 0.07 -0.04 0.13 0.32 -0.49 0.04 0.10 -0.38 0.52 0.47 0.56 0.32 0.46 -0.08 0.40 1
VB3 -0.05 0.05 0.05 0.05 0.14 0.07 -0.30 -0.26 -0.02 0.06 0.06 0.02 0.02 0.02 0.02 0.02 0.23 0.09 0.06 0.14 0.29 -0.19 0.01 0.04 -0.04 0.61 0.65 0.55 0.61 0.37 0.21 0.34 0.76 1
Bold font: NS (the P values are greater than 0.01)
Abbreviations used in correlation matrix
MC: Moisture content TS: Total solids A: Ash TSS: Total soluble solids CF: Crude fiber F: Fat
FA: fatty acids Pro: Protein CH: Carbohydrate NFE: Nitrogen free extract E: Energy value AA:
Acetic acid
CA: Citric acid OA: Oxalic acid TA: Tartaric acid Cu: Copper Fe: Iron Zn:
Zinc
Mn: Manganese Ca: Calcium Mg: Magnesium Na: Sodium K: Potassium Alk:
Alkaloids
Sap: Saponins Fla: Flavinoids Phe: Phenol Tan: Tanins V: Vitamin
245
Appendix XLI. Analysis of variance for sensory analysis of uncooked vegetables
Parameters DF SS MS F P
Appearance 4 10.720 2.680 3.865 0.009
Color 4 8.080 2.020 2.942 0.030
Odor 4 4.120 1.030 1.280 0.292
Texture 4 4.520 1.130 1.963 0.116
Taste 4 2.120 0.530 0.491 0.742
Acceptability 4 0.920 0.230 0.292 0.881
Purchase 4 3.320 0.830 0.679 0.610
Appendix XLII. Analysis of variance for sensory analysis of cooked vegetables
Parameter DF SS MS F P
Appearance 4 0.600 0.150 0.118 0.976
Taste 4 5.120 1.280 1.895 0.128
Aroma 4 1.120 0.280 0.420 0.793
Texture 4 5.080 1.270 1.647 0.179
Purchase 4 0.920 0.230 0.236 0.917
Acceptability 4 3.280 0.820 0.703 0.594
246
Appendix XLIII. Informed Consent
From: Benish Nawaz Mirani
Subject: Consent to Participate
Dear Sir:
I (participant), agree to participate in this research project conducted by Benish Nawaz
Mirani, Student at Institute of Food Sciences and Technology, Sindh Agriculture
University Tandojam. I understand the purpose of this study is to examine how Lower
Sindh residents of District Mirpurkhas navigate their nutrition environment to obtain the
foods they eat. I understand my participation is strictly voluntary and may refuse to
answer any question without penalty. I am also informed that my participation will last
approximately 30 minutes.
I understand that my response to the questions will be written, and that these forms will
be transcribed/stores and kept in a locked file cabinet. Afterward, these forms will be
destroyed. I understand questions or concerns about this study are to be directed Benish
Nawaz Mirani, or her advisor Dr. Saghir Ahmed Sheikh, Institute of Food Sciences and
Technology, Sindh Agriculture University Tandojam.
Miss Benish Nawaz has explained in Sindhi the information above and any questions I
asked have been answered to my satisfaction. I agree to participate in this activity and
know my responses will be recorded. I understand a copy of this form will be made
available to me for the relevant information and phone numbers.
“I agree ______ I disagree______to have my responses recorded on audio/video tape.”
“I agree ______I disagree______that (researcher name) may quote me in his/her paper”
________________________________________________________________________
Participant signature and date
This survey has been reviewed and approved by the IFST, SAU Tandojam. Questions
concerning your rights as a participant in this research may be addressed to the Director
IFST, SAU Tandojam. Thank you for taking the time to assist me in this research.
247
Appendix XLIV:
Questionnaire non-traditional vegetables
Name of respondent: _____________________________________ S.No.
Education level: _____________ Age (yrs): Gender: M F
Village: ________________________ District: __________________
Farming experience (yrs): __________ Land holding (acres): _______
Interviewer Name: __________________ Interview date: ____________
S# Vegetable
Name
Eat
frequently
Eat
occasionally
Never
tasted
Do not
know
4 3 2 1
1
2
3
4
5
8. If never tasted, then
Name of
vegetable
Dislike Can’t get
(not available)
Can’t cook Other
(Specify)
248
Appendix XLV:
Sensory evaluation form
(For cooked vegetables)
Name of Expert age; Gender M F
Recipe Name: Category:
Directions: Tick one rating in the boxes for each of the following: Appearance,
taste/flavor, texture/consistency, aroma/smell, and overall acceptability
Parameter Point scores (on five point scale 1-5)
5 4 3 2 1
Appearance Extremely
Attractive
Moderately
Attractive
Attractive
Unappealing Fair
Taste/Flavor Tasted great Flavorful Acceptable Off flavor Flavor did not
appeal to me
Texture
rating
Wonderful
texture
Good texture Acceptable
texture
Off texture Inappropriate
texture/flat/runny
Aroma/
Smell rating
Wonderful
aroma
Appealing
aroma
Acceptable
aroma
Aroma is not
appealing
Unappetizing
aroma
Overall
acceptability
Extremely
Acceptable
Moderately
Acceptable
Acceptable Moderately
Unacceptable
Unacceptable
Purchase Definitely
would
Probably
would
Might or
might not
Probably would
not
Definitely would not
249
Appendix XLVI:
Sensory evaluation form
(For raw or uncooked vegetables)
Name of Expert: age: Gender: M F
Vegetable Name: Date:
Directions: Tick one rating in the boxes for each of the following: Appearance, color,
odor, texture/consistency, taste, and overall acceptability
Parameter Point scores (on five point scale 1-5)
5 4 3 2 1
Appearance Extremely
attractive
Moderately
attractive
Attractive
Fair
Unappealing
Color Typical green Green (typical) with
scarce dark-green or
light-green
spots
Green with
numerous
spots
Yellow-
green or
mostly dark-
green
Dark-green
or yellow
Odor Very intrinsic
very intensive
Intrinsic
intensive
Medium
intrinsic
medium
intensive
Rather
extrinsic
weakly
intensive
Off-odor
undetectable
Texture
consistency
– leaf
tenderness
– moisture
Very crisp,
firm
dry leaves
Crisp, firm
slightly moist leaves
Medium firm,
slightly soft
moist leaves
Not firm,
soft,
slightly
gummy
moist,
slightly
sticky leaves
Gummy or
sticky
very wet,
strongly
stuck leaves
Taste Very intrinsic,
desirable
Intrinsic, desirable Medium
intrinsic,
rather desirable
Not intrinsic Off-flavor
Overall
acceptable
Extremely
acceptable
Moderately
acceptable
Acceptable Moderately
unacceptable
Unacceptable
Purchase Definitely
would
Probably would Might or might
not
Probably
would not
Definitely
would not
250
PLACE OF WORK Sindh Agriculture University, Tandojam.
DURATION OF WORK Three years
EDUCATIONAL UNIT INVOLVED Institute of Food Sciences & Technology Faculty of Crop Production
Sindh Agriculture University, Tandojam. And
National Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro.
SUPERVISOR PROF. DR. SAGHIR AHMED SHEIKH
Professor
Institute of Food Sciences & Technology,
Faculty of Crop Production,
Sindh Agriculture University, Tandojam.
CO-SUPERVISOR-I PROF. DR. SHAFI MUHAMMAD
NIZAMANI
Professor
National Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro.
CO- SUPERVISOR-II PROF. DR. AIJAZ HUSSAIN SOOMRO
Professor
Institute of Food Sciences & Technology,
Faculty of Crop Production,
Sindh Agriculture University, Tandojam.
STUDENT Benish Nawaz