Effect of Addition of Salts and Curing

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EFFECT OF ADDITION OF SALTS AND CURINGTREATMENT ON WATER-HOLDING CAPACITY AND

MICROBIAL STABILITY OF BEEF

AIZUDDIN BIN AHMAD IMRAN

BACHELOR OF SCIENCE (Hons.)FOOD SCIENCE AND TECHNOLOGYFACULTY OF APPLIED SCEINCES

UNIVERSITI TEKNOLOGI MARA

JANUARY 2012


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This Final Year Project Report entitles Effect of Addition of Salts and

Curing Treatment on Water-holding Capacity and Microbial Stability.

was submitted by Aizuddin Bin Ahmad Imran, in partial fulfilment of the

requirements for the Degree of Bachelor of Science (Hons.) Food Science and

Technology, in the Faculty of Applied Sciences, and was approved by

Assc Prof Dr. Hjh Halimahton Zahrah bt Mohamed Som

Supervisor

B.Sc. (Hons.) Food Science and TechnologyFaculty of Applied Sciences

Universiti Teknologi MARA

40450 Shah AlamSelangor

Prof. Madya Dr. Anida bt. Yusof Prof. Madya Dr. Noorlaila bt.AhmadProject Coordinator Programme Coordinator

B. Sc. (Hons.) Food Science and B. Sc. (Hons.) Food Science andTechnology Technology

Faculty of Applied Sciences Faculty of Applied Sciences

Universiti Teknologi MARA Universiti Teknologi MARA

40450 Shah Alam 40450 Shah AlamSelangor Selangor

Date: ......................


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ACKNOWLEDGEMENTS

In the name of Allah, the Most Gracious and the Most Merciful, His

willingness has allowed me to accomplish this research project.

Upon completion of this project, I would like to express the deepest

appreciation and heartful thanks to my supervisor, Assc Prof Dr. Hjh.

Halimahton Zahrah bt Mohamed Som, who always encouraged, guided and

gave moral support from the initial stage until this research was completed and

because of that it enabled me to develop an understanding of the subject and

completed this project successfully. Without her guidance and persistent help,

this research project would not have been possible. A thousand thanks are also

dedicated to my parents and my siblings especially my father, En. Ahmad

Imran bin Mohd Yusoff who never stopped giving me advice, financial and

moral supports and also prayed for me to succeed in the completion of this

research project.

Special thanks are also dedicated to Assistance Science Officer, Madam

Norahiza Mohd Soheh and also the Lab Staff, Madam Siti Marhani Mardi, Mr.

Osman Abd Rahman, Sir Muhammad Fadzli Kamarudin and Miss Nor

Suhadah Mohd Samri for their support.

Lastly, I offer my regards and blessings to all of those who supported me in any

way during the completion of the project by discussing, sharing and

exchanging ideas especially lecturers and classmates and also everyone who

was involved directly or indirectly in this my research project.

Thank you so much.

Aizuddin Bin Ahmad Imran


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TABLE OF CONTENTS

Page

ACKNOWLEDGEMENTS iii

TABLE OF CONTENTS iv

LIST OF TABLES vi

LIST OF FIGURES vii

LIST OF ABBREVIATIONS viii

ABSTRACT ix

ABSTRAK x

CHAPTER 1 INTRODUCTION 11.1 Background 1

1.2 Significance of study 2

1.3 Objectives of study 3

CHAPTER 2 LITERATURE RIVIEW 4

2.1 Meat and meat quality 4

2.1.1 Texture and tenderness 5

2.1.2 Water-holding capacity and juiciness 6

2.1.3 Colour 72.1.4 Odour and taste 7

2.2 Water-holding capacity of meat 8

2.2.1 Functions of water-holding capacity 11

2.2.2 Factors affecting water-holding capacity 11

2.3 Salts and their effects 13

2.3.1 Salts limitation 14

2.4 Microbial content 15

CHAPTER 3 METHODOLOGY 163.1 Material 16

3.2 Methods 16

3.2.1 Preparation of sample 17

3.2.2 Preparation of control 17

3.2.3 Preparation of sodium chloride solutions 17

3.2.4 Preparation of sodium polyphosphate solutions 18


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3.2.5 Curing treatment 19

3.2.6 Total plate count (microbial analysis) 19

CHAPTER 4 RESULT AND DISCUSSION 20

4.1 Addition of salts 20

4.2 Water-holding capacity (WHC) 21

4.2.1 Effect of sodium chloride (NaCl) 21

4.2.2 Effect of sodium polyphosphate 24

4.2.3 Effect of curing treatment 25

4.3 Microbial stability 29

4.3.1 Effect of addition of salts 29

4.3.2 Effect of curing treatment 31

4.3.3 Overall overview 32

CHAPTER 5 CONCLUSION AND RECOMMENDATIONS 34

CITED REFERENCES 35

CURRICULAR VITAE 38


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LIST OF TABLES

Table Caption Page

2.1 Volatile components of cooked beef aroma 9

4.1 WHC of NaCl treated beef 22

4.2 WHC of sodium polyphosphate treated beef 24

4.3 WHC of cured samples 26


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LIST OF FIGURES

Figure Caption Page

2.1 Structure of striated skeletal muscle 5

2.2 Structure and composition of myofibril 12

2.3 Scheme of proposal for the action of nitrate in beef 14

4.1 WHC of beef treated by NaCl 22

4.2 WHC of beef treated by sodium polyphosphate 24

4.3 WHC of beef treated by curing treatment 26

4.4 Cured meat at 50ppm and control meat 27

4.5 Overall WHC of meat by all treatments 28

4.6 Effect of NaCl on microbial stability of meat 30

4.7 Effect of sodium polyphosphate on microbial stability of meat 31

4.8 Effect of curing treatment on microbial stability 32

4.9 Effect of overall treatments on microbial stability 33


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LIST OF ABBREVIATIONS

CFU/mL : Coliform-forming unit / mililitre

cm : Centimetre

DCB : Dark-cutting beef

Fig : Figure

g : Gram

g : Gravity

kg : Kilogram

M : Molar (mol / litre)

mL : Millilitre

NaOH : Sodium hydroxide

ppm : Parts per million (mg / kg)

WHC : Water-holding capacity

% : Percentage

oC : Degree celcius


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ABSTRACT

EFFECT OF ADDITION OF SALTS AND CURING TREATMENT ON

WATER-HOLDING CAPACITY AND MICROBIAL STABILITY OF

BEEF

The experiment was done to determine the effect of sodium chloride, sodium

polyphosphate, and curing treatment (sodium nitrate and sodium nitrite) on the

WHC and microbial stability of beef. WHC was determined by centrifugal method

while microbial stability was determined by total plate count method. The results

obtained showed that the most effective salt for increasing WHC of beef was

sodium polyphosphate followed by sodium chloride and then curing treatment.

WHC is related to microbial stability of beef as the higher the WHC of beef, the

higher total plate count (CFU/mL) of beef observed.


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ABSTRAK

KESAN PENAMBAHAN GARAM DAN RAWATAN PEMERAPAN

TERHADAP KAPASITI MEMEGANG AIR DAN KESTABILAN

MIKROBIAL DAGING

Eksperimen dijalankan bagi menentukan kesan natrium klorida, natrium

poliphosphat dan rawatan pemerapan (natrium nitrat dan natrium nitrit) pada

kapasiti memegang air dan kestabilan mikrobial daging. Kapasiti memegang air

ditentukan dengan menggunakan kaedah penggempar sementara itu kestabilan

mikrobial ditentukan dengan kaedah jumlah kiraan piring. Keputusan yang

diperoleh menunjukkan garam yang paling efektif untuk meningkatkan kapasiti

memegang air daging adalah natrium poliphosphat diikuti dengan natrium klorida

dan rawatan pemerapan. Kapasiti memegang air adalah berkait dengan kestabilan

mikrobial daging iaitu semakin tinggi kapasiti memegang air daging, semakin

tinggi jumlah kiraan piring (CFU/mL) daging yang diperhatikan.


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CHAPTER 1

INTRODUCTION

1.1 Background

Meat is defined as the flesh of animals used as food. The bulk of meat consumed

is derived from cattle, sheep, and pig. The increasing pressure of world

population and the need to raise living standards has been made the production

of more and better meat and its effective preservation, an important issue

(Lawrie, 1998).

Beef meat that is from the cow has several parts that are specified for

consumers convenience. Each part of the beef has different texture value suchas firm, soft, or hard. The composition of meat at different parts of the cow also

differs such as fat content and protein content. Later as the scientific research

became wider on food especially meat, the research on meat quality became

more interesting. There are four attributes to define the eating quality of meat

which are its texture and tenderness, water-holding capacity (WHC) and

juiciness, colour, and odour and taste. All these four attributes are important for

meat quality but this study focuses on WHC and the factors affecting it.

It is important to understand how WHC reacts with each factor especially with

the addition of salts. Direct relation between WHC and microbial content in meat

is still fully not understood. As an example, when the additions of salts are made

to increase the WHC of meat, the salts themselves are the preserving agents. As


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WHC is important for the quality of meat, the microorganism attack on meat due

to favourable condition should be avoided. Botulism is a common disease related

to meat and meat products, and eventually nitrates are known to prevent the

disease. Nitrate is used in curing meat to give a better colour and at the same

time can prevent botulism caused by Clostridum botulinum, but usage of nitrates

must be controlled as they are toxic at high dose. It was reported that the addition

of nitrate to a pickling solution could lead to the formation of nitrite due to the

action of some microorganisms in the brine (Honikel, 2007).

Besides the addition of salts to preserve meat, freezing is a common practice

done by many people today around the world. Freezing may affect WHC of meat

due to the formation of ice crystals that may damage fibre muscle and hence

reduce the ability to bind water. However, there are different methods of freezing

that can avoid the formation of large ice crystals such as high-pressure freezing

and rapid freezing. Thawing is a defrosting process of frozen food and thawing

method actually can affect the WHC of meat (Li & Sun, 2001). According to Li

and Sun (2001), faster thawing will prevent reduction in WHC of meat as

compared to slow thawing method.

1.2 Significance of study

In this study on the effect of addition of salts on WHC of beef, the results

obtained can be used to improve the quality of beef in terms of WHC and

juiciness specifically. The results can also be used by consumers and food

industries which use beef or other meat products, in order to obtain high quality

meat. The study also can improve on the understanding of WHC of beef. The

microbial analysis (total plate count) that will be conducted will give information

on the relation between additions of salts the microbial load of beef and hence

this may increase our understanding of preservation of meat by the addition of

salts.


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1.3 Objectives of study

The objective of the study was to determine the effect of the addition of salts and

curing treatment on the WHC and microbial stability of beef.


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CHAPTER 2

LITERATURE REVIEW

2.1 Meat and Meat Quality

Meat is mainly defined as the flesh of animal that can be used as food for people.

Other parts of animal such as kidney, liver, brains, and other edible tissues which

are internal organs can also be classified as meat (Lawrie, 1998). Meat and meat

products are classified as sources for protein and also important sources for fat,

essential amino acids, minerals and vitamins and other nutrients (Biesalski,

2005). The consumption of meat in Malaysia is derived from cattle and buffalo.

As time goes by, there is increasing demand for meat and this increased the

demand for more and better quality meat, hence effective preservation method isthe most important issue. Nowadays, a better livestock system has been done to

increase higher production of beef. The quality of meat generally depends on its

colour, WHC and juiciness, texture and tenderness, and odour and taste. These

four factors are crucial to control as lack of monitoring and controlling these

factors can cause undesirable quality of meat especially in beef. Basically, the

meat muscle consists of 75% water, 20% protein, 3% fat, and 2% soluble non-

protein substances (Tornberg, 2004). Since the water content of meat is high,

meat juiciness will be affected if this water content is disturbed. Figure 2.1

shows the structure of striated skeletal muscle.


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Figure 2.1 Structure of striated skeletal muscle

(Source: http://foodslashscience.blogspot.com/2010/11/cooking-meat-thermodynamics-

and.html)

2.1.1 Texture and tenderness

From all four factors that affect quality of meat, texture and tenderness are the

most important factor as compared to the colour, WHC and juiciness, flavour,

and odour. Texture is referred to the bundles of fibres that contain connective

tissues which divide the muscle longitudinally. There are two types of muscles;

which are coarse-grained muscles which are large bundles and fine-grained

muscles that have small bundles. Generally, coarseness of texture depending on

four factors which are age of animals, sex of animals, frame size, and also breeds

(Lawrie, 1998). There is a correlation between muscle fibre diameter and

tenderness of meat. Meanwhile, the overall impression of tenderness includes

texture which involves three aspects: firstly, the initial ease of penetration of the

meat by the teeth; secondly, the ease with which the meat breaks into fragments;

and thirdly, the amount of residue remaining after chewing (Weir, 1960).


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2.1.2 Water-holding capacity (WHC) & juiciness

WHC is closely related to the juiciness of meat. Juiciness is important in

determining the taste of the meat, and the degree of shrinkage on cooking loss is

directly correlated with loss of juiciness. Juiciness in cooked meat has two

organoleptic components. The first is the impression of wetness during the first

chews and is produced by the rapid release of meat fluid; the second is one of

sustained juiciness, largely due to the stimulatory effect of fat on salivation

(Lawrie, 1998). It is easy to understand that the good quality of meat or a better

quality is the one that is juicier.

The process of freezing basically does not itself affect the juiciness of meat

because studies have shown that there is no significant difference in meat which

has been chilled or frozen and held for the same length of time. However, the

storage time caused an effect in juiciness. Thus, the beef that was held at -10oC

for 20 weeks was much less juicy than the corresponding beef that was held for

few days at 0oC (Lawrie, 1998). Meat with high ultimate pH has a better

juiciness as compared to the meat with low ultimate pH before and after

freezing. Such meat that has low ultimate pH is like pork and therefore it has low

WHC and the meat is exudative.

Another study reported that muscle that had a high content of intra-muscular fat

tend to have a high WHC and the clear reason for this phenomenon is unknown,

with the possibility that intramuscular fat loosens up the microstructure, thus

allowing more water to entrain. As juiciness and WHC has a very close relation,

it is useful to study on WHC of meat to ensure the juiciness of meat can be at the

optimum level. Hence, this may increase the quality of meat after cooking.

Increase in demand of good quality meat has made the study of improving

quality of meat worthwhile. Besides texture, juiciness of meat may also be


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important to consumers and it is perceived as a factor contributing to the quality

of meat. Thus, many scientists did research in WHC area of meat such as protein

interaction and ionic strength and factors that can affect these.

2.1.3 Colour

Colour of meat has been one of the quality factors consumers look upon when

buying meat. Colour also can affect someones mind to accept the meat or not.

There are several types of colour that can be observed around the market area

such as dark, pinkish, or pale. Most of beef colour is dark-cutting beef (DCB)

and it is due to the high concentration of myoglobin. Since 1932, principalpigment of muscle was crystallised and it was shown that myoglobin was not

identical with the haemoglobin of the blood, it has been accepted that the colour

of meat is not substantially due to the haemoglobin unless bleeding has been

faulty (Lawrie, 1998). The colour of meat does not depend only on the

concentration of myoglobin but also on its type of molecule, on its chemical state

which are myoglobin, oxymyoglobin, and metmyoglobin. It is clearly

recognised by people now that high level of muscular activity increases the

myoglobin concentration and this may differ in different species, breed, sex, age,

type of muscle and training. Another factor that can cause different concentration

of myoglobin is nature of nutrition diet with low iron leads to low

concentration of myoglobin. In the fresh meat, before it been cooked, the most

important chemical form is oxymyoglobin. Even though it occurs on the surface

only, this is the major pigment that is important, since it represents the bright red

colour of meat desired by consumers.

2.1.4 Odour and taste

Odour and taste are classified under flavour and flavour is a complex sensation

in which each person may have different point of view. Odour and taste are the


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most difficult to define as compared to other flavours such as sweet, bitter, sour,

or saline. Gas chromatography can measure the volatile compounds in food. The

desirable taste and odour of meat normally only occurs when meat is cooked.

Without cooking, the taste of meat is bland and this is because of the

biochemical state and origin (Lawrie, 1998). It is reported that Crocker found

that water-soluble dialysates of muscle contained inosinic acid and glycoprotein

that will give meaty odour during heating. There are numerous chemical

compounds that contribute to meaty flavour such as amino acids of the

glycoprotein. However, even though the meat extracts containing these amino

acids are heated, it does not result in meat odour because the sequence of amino

acids is important in meat flavour. Besides amino acids, carbohydrates of meat

are also important in producing flavour when heated (Lawrie, 1998). They lose

water and form furfural from pentoses and hydroxymethylfurfural from hexoses.

At higher temperature, caramelisation formed a large number of odoriferous

compounds, including furans, alcohols, and aromatic hydrocarbons (Table 2.1).

2.2 Water-holding capacity of meat

Water is most important as natural or added constituent of almost foods. Meat is

a very complex structure and myofibrillar protein system has developed to

perform very fast and highly specific repetitive movements. Water in the muscle

eventually acts as a lubricant, as well as a medium to transport metabolites in the

fibre (Puolanne and Halonen, 2010). Most of the water in muscle is present in

the myofibrils, in the spaces between the thick filaments of myosin and the thin

filaments of actin or tropomyosin (Lawrie, 1998). In order to be able to

understand and control changes in WHC, the main question that arises is how

water is accumulated and lost. Exudation of fluid is known as weep in

uncooked meat which has not been frozen, as drip in thawed uncooked meat,

and as shrink in cooked meats.


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Table 2.1 Volatile components of cooked beef aroma (Lawrie, 1998).

Type No. Identified

Aliphatic hydrocarbons 73

Alicyclic hydrocarbons 4Terpenoids 8

Aliphatic alcohols 46

Aliphatic aldehydes 55

Aliphatic ketones 44

Alicyclic ketones 8

Aliphatic carboxylic acids 20

Lactones 32

Aliphatic esters 27Aliphatics ethers 5

Aliphatic amines 20

Chlorinated compounds 10

Benzoid compounds 86

S-compounds (non-heterocyclic) 68

Furans and derivatives 43

Thiophenes and derivatives 40

Pyrroles and derivatives 20

Pyridines and derivatives 17

Pyrazines and derivatives 54

Oxazoles and oxazolines 13

Thiazoles and thiazolines 29

Other S-heterocycles 13

Miscellaneous 12

Source: Lawrie (1998)

Water exists in at least two environments in the muscle, which are bound

water or free water. These types of water can relate to the WHC of muscle. In

beef muscle, it has been demonstrated that WHC decreased within 48 hours

postmortem and there was relatively rapid release of drip over the first day and


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this was slower in the next day (Joo et al., 1999). The loss of water-holding

ability can be caused by shrinkage of filament lattice that is brought by pH fall

closer to the isoelectric point (5.5 5.7), rigor contraction, and myosin

denaturation. Myofibrillar shrinkage occurs faster in pale-soft-exudative (PSE)

muscle than in normal muscle (Joo et al., 1999). Cooking can induce structural

changes, which may decrease WHC of meat. Therefore, it is known that

structural changes in the connective tissue network and the muscle fibres can

lead to lower WHC that is mainly due to shrinkage.

Comminuted meat or meat products such as hamburger patties or sausages are

different as their muscle fibres have already been destroyed during processing

(mincing). However, the WHC of comminuted meat is almost up to the whole

meat. Tornberg (2004) reported that although hamburgers have been

comminuted, the cooking losses are almost as large as whole meat. This situation

is probably due to the more prevalent shrinkage of whole fibres and pieces of

fibres. Freezing may cause in tissues damage and this can affect the WHC of

meat. This occurs because of slow freezing which may cause formation of large

ice crystals. However, fast-rate freezing can avoid large ice crystals to form andthis may reduce the damage tissues and hence will not reduce meat WHC.

A comparative study has been done on high-pressure freezing with that by air-

blast and liquid nitrogen, and found that high-pressure frozen samples showed

uniform, small ice crystals both at surface and at the central zones (Li and Sun,

2001). Freezing process is often considered as one of the causes of reduction in

meat quality, while thawing process has also been cited as a contributor to this

quality reduction (Ambrosiadis et al., 1994). Freezing is not the main factor in

WHC decreasing but the period of freezing is (Lee et al., 2008). The analysis

done on drip loss of thawed and fresh sample showed a significant difference


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between both of them but there was no signifcant difference between types of

thawing methods (Ngapo et al., 1999).

2.2.1 Functions of WHC

The understanding of WHC of meat has improved with time, with researchers

playing an important role in studies on meat structure and WHC. Water binding

ability of meat is the ability of meat to bind or hold water in the protein layer.

Free water in meat is easily driven out but the bound water in meat that is tightly

bound need pressure to be driven out. The major functions of WHC in meat are

more in giving juiciness and keep the meat moist and if WHC of meat is low, thequality of meat can greatly reduce. Meat can hold water but it depends on several

basic factors such as pH, protein fold, ionic strength, addition of salts, and other

factors that are still on study.

2.2.2 Factors affecting WHC

There are a lot of factors that affect WHC of meat. To understand it in deeper

knowledge, thorough reading on WHC is important. Water-holding is caused by

electrostatic repulsion between myofibrillar proteins (myofillaments) which may

result in swelling of myofibrils (Puolanne and Halonen, 2010). Polar groups that

exist at the side chains of the amino acids bind water molecules on their surfaces

by Van der Waals forces. There is one factor that limits the swelling of

myofibrils and the factor is the actomyosin cross-bridges between filaments and

the Z-lines. The structure of myofibrils is shown in Figure 2.2.


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Figure 2.2 Structure and composition of myofibril

(Source: http://meat.tamu.edu/structure.html)

In a study of long term freezing, WHC was decreased and this was due to

myofibrillar shrinkage caused by the formation of ice crystals, which may

damage muscle cells and caused protein denaturation (Lee et al., 2008). Protein

network net charge may change and this is because of the pH, thus this change in

protein network net charge that may affect the degree of swelling. Without

addition of salt, swelling was maximum at pH 3.0 and minimum at pH 5.0 (pH

5.0 is the average isoelectric point of meat proteins) and from there a constant

increase within physiological pH range of pH 6.4 to 7.2 (Puolanne and Halonen,

2010). Salts may increase WHC of meat at certain concentration, and salts may


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contribute to this factor because of the effect of ion distribution in the sarcomere,

with the effect being different between Na+

and K+.

Amino acids play a role in water-binding ability. Negatively charged amino acid

side chains are strongly hydrated, while the positively charged are weakly-

hydrated. The two amino acids that have the highest water-binding ability are

aspartic acid and glutamic acid (Puolanne and Halonen, 2010). Curing of meat

may raise the ionic strength of meat from post-mortem values; this may increase

the WHC of meat. Besides that, thawing method may also affect the WHC of

meat and slow thawing rate may increase in drip loss as compared to the fast

thawing rate (Ngapo et al., 1999). Fast thawing rate was achieved by immersing

the frozen meat in water while slow thawing rate was achieved by allowing meat

to stand in the air at 4oC. High-pressure thawing is a new application and it is

proven that it can preserve food quality and reduce necessary thawing time and

hence reduced water-binding ability loss (Li and Sun, 2001).

2.3 Salts and their effects

Since ancient time, salts have been used to preserve food including meat. This is

done because no freezing equipment was yet available to preserve meat. The

efficacy of the process, arises primarily from the discouragement to microbial

growth caused by the enhanced osmotic pressure in such products (Lawrie,

1998). NaCl is added to the meat to give flavour besides preserving it.

Sometimes, sugar is also used. By adding NaCl, the flavour of the meat is

improved and eventually it can extend the shelf life. Sodium pyrophosphate,

Na2P4O7, is also used in meat products to bind water as the fibres in meat that

have been comminuted are damaged. Na2P4O7 is normally used with NaCl in the

meat products. However, the usage of Na2P4O7 is not high, at about 0.5% to

1.0% only. Na2P4O7 is used due to its beneficial effects in improving


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functionality, palatability, and storage stability of meat. Pyrophosphate can

enhance sausage or meat products quality with respect to WHC, meat particle-

particle binding, emulsion stability, cook yield, and colour, flavour and texture

(Beom et al., 1997).

Curing of meat is done to preserve colour mainly and nitrates and nitrites have

been used. However, the amount of nitrates and nitrites must be controlled as

they can be health hazards. Nitrates and nitrites impart the bright reddish and

pink colour which is desirable in a cured product. Another function of nitrates

and nitrites is the effect on flavour, without them a cured ham would be simply a

salty pork roast (Federick, 1973). Sodium nitrites also can prevent the growth of

a food poisoning microorganism known as Clostridium botulinum, that can cause

botulism. The reactions of nitrate are shown below in Figure 3.2 below.

Nitrate (NaNO3) reduction by microorganisms nitrite (NaNO2)

NaNO2 + H+ HNO2 + Na+

2HNO2 N2O3 + H2O

NO + myoglobin NO-myoglobin

Figure 2.3 Scheme of the proposal for the action of nitrate in beef.

Source: Honikel (2007)

2.3.1 Salts limitation

Salts that are used on meat whether to preserve, impart flavour or colour require

limitation as some salts used may give adverse effects on health. Nitrates and

nitrites combination must not exceed 200ppm as stated in the Malaysian Food

Documents

Effect of Addition of Salts and Curing