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KITCHEN CHEMISTRY PROJECT 2011
TITTLE: BEST PICKLED
NINA ALLYZA BINTI KEPOL (D20091035080)
NUR AYUNI BINTI ROZAKI (D20091035084)
NOR ASMALIZA BINTI BAKAR (D20091035095)
NUR ‘ALIA AFIFAH BINTI HAMDAN (D20091035076)
ABSTRACT:
Some food only long lasting if it is stored in a different way from its original form such as
preservations. One of the preservations methods is pickling. Pickling is the process of preserving
food by anaerobic fermentation in brine (a solution of salt in water) to produce lactic acid,
or marinating and storing it in an acid solution, usually vinegar (acetic acid). We chose mango
for our best pickled because it is easily found in Malaysia. This experiment is conducted to find
the best method to obtain the best pickled including to study how lime water effect the condition
of pickled and also to study how the concentration of solution affect the texture of pickled. First
thing that we need to do was cleaned and sterile the container that going to be used as well as the
mango itself. After that, the cut mango was divided into three parts which are soaked in lime
water for 5 minutes, 30 minutes and 60 minutes. Each of these parts then will be divided into
another three parts which are different in the amount of ingredient. The observation was first
made on the effect of lime water on the crunchiness of the mango. The crunchiest was then
selected from the first observation for the second observation, where the color, crunchiness, and
taste were considered to be observed. After that, the best pickled was concluded. From the result
obtained, we found that the, the crunchiest and best mango pickled was the mango that soaked
into the lime water for 60 minutes and contain sugar and salt only as its ingredients. So we
conclude that, the longer the mango is soaked into the lime water the crunchier it will be and the
combination of salt and sugar give the best pickled.
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KITCHEN CHEMISTRY PROJECT 2011
INTRODUCTION
Pickling is a global culinary art. If
you were to go on an international food-
tasting tour, you’d find pickled foods just
about everywhere. There are two basic
categories of pickles. The first type includes
pickles preserved in vinegar, a strong acid in
which few bacteria can survive. Most of the
bottled kosher cucumber pickles available in
the supermarket are preserved in vinegar.
The other category includes pickles soaked
in a salt brine to encourages fermentation—
the growth of "good" bacteria that make a
food less vulnerable to "bad" spoilage-
causing bacteria. Common examples of
fermented pickles include kimchi and many
cucumber dill pickles. In chemical pickling,
the jar and lid are first boiled in order to
sterilize them. The fruits or vegetables to be
pickled are then added to the jar along with
brine and/or vinegar as well as spices and
are then allowed to ferment until the desired
taste is obtained. In commercial pickling, a
preservative like sodium benzoate or EDTA
may also be added to enhance shelf life. In
fermentation pickling, the food itself
produces the preservation agent, typically by
a process that produces lactic acid. Pickling
is not only an international food-
preservation technique, it’s also an ancient
one. For thousands of years, our ancestors
have explored ways to pickle foods,
following an instinct to secure surplus food
supplies for long lasting. Here we also try to
test what is the best way in making pickle.
Another thing that we must take note, pickle
cannot be too much consumed because the
World Health Organization has listed
pickled vegetables as a possible carcinogen
and the British Journal of Cancer released
an online 2009 review of research on pickles
as increasing the risks of esophageal cancer
METHODOLOGY
1. Cut the mango into small pieces of
the same size. (Almost the same)
2. Divide the mango into three parts.
3. Soak the first sample into lime water
for 5 minutes, the second sample for
30 minutes and the third sample for
60 minutes.
4. Remove the mangoes from lime
water, and then rinse with tap water.
5. Divide the first sample into four and
add into the container that labeled A,
B, C and D.
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KITCHEN CHEMISTRY PROJECT 2011
container Contents
A 26.06 g of sugar +
250 ml of water
B 25.37 g of salt + 250
ml of water
C 25.37 g of salt +
26.06 g of sugar +
250 ml of water
D 26.06 g of sugar +
6 pieces of asamboi
+ 250 ml of water
6. Leave the labeled containers at a dry
place for six days.
7. Repeat step 4 until 6 by replacing the
first sample with the second and third
sample.
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KITCHEN CHEMISTRY PROJECT 2011
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KITCHEN CHEMISTRY PROJECT 2011
RESULTS
SAMPLES TIME
(MIN)
OBSERVATION
ON
CRUNCHINESS
A 5 Less crunchy
30 Moderately
crunchy
60 Very crunchy
B 5 Less crunchy
30 Moderately
crunchy
60 Very crunchy
C 5 Less crunchy
30 Moderately
crunchy
60 Very crunchy
D 5 Less crunchy
30 Moderately
crunchy
60 Very crunchy
After the time with best result has
been selected (60 minutes), the
second comparison is done.
5
container observation
A (60) Brown in color
Quite taste
The least
crunchy
B (60) The original
color is
remained
Not delicious
at all (too
salty)
The most
crunchy
pickled
C (60) Very delicious
The original
color is
preserved
very crunchy
D(60) Bubbles
formed in the
solution
Reddish
orange in color
Quite tasty
Less crunchy
KITCHEN CHEMISTRY PROJECT 2011
DISCUSSION
Ingredients
In the experiment, a different
substance was added in each container.
Container A was added with sugar and
water, container B was added with salt and
water, container C was added with water,
sugar and salt while container D was added
with water, sugar and ‘asamboi’.
The pickled in container A was
quite tasty because it tasted sweet which
came from the sugar. Sugar plays an
important role in the food preservation. This
is because sugar is able to form hydrogen
bond with water molecules in which will
reduce the water activity and make the water
less favourable for microbial growth. From
the reading, it was found that the winter
radish root will appear bright yellow in color
that occurs naturally after the pickling
process. The condition for the formation of
yellow pigment is the same as the reaction
between thioglucosidase and ascorbic acid
that stimulate the production of yellow
pigment (Ozawa et al., 1993). However, in
this case the yellowing or browning of the
pickled might be caused by some errors that
were done during conducting the study. The
mango might be not soaked fully in the
sugar solution which caused it be exposed to
oxygen and oxidized. The enzyme that
responsible for the browning of the mango is
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KITCHEN CHEMISTRY PROJECT 2011
polyphenol oxidase. This enzyme caused the
formation of oxidized pigment which is
brown in color and contributed to the color
changes in the mango.
The addition of salt in the container
B has promoted the growth of bacteria
known as Lactobacillus plantarum.
However salt must be added at a correct
proportion. If too much salt was added, the
good bacteria will not function properly and
too little salt will promote the growth of less
beneficial bacteria.
The pickled in container C has the
best taste because it has a balance taste. It
was not too sweet and does not too salty, in
fact it has both of the combination of the
tastes.
The solution in container D was
quite different from the others, it was added
with ‘asamboi’ which gave the solution an
orange color. The solution was orange in
color because the paticles in ‘asamboi’
which was orange in color has diffused
throughout the water in the container via
simple diffusion. The orange solution has
stained the pickled with an orange color.
Lime Water
Processing is necessary for
all pickles and relishes to destroy the yeasts,
molds and bacteria that may cause the
product to spoil and also to inactivate
enzymes that could affect color, flavour and
texture of the pickled product.
Calcium hydroxide, traditionally
called slaked lime, is an inorganic
compound with the chemical formula Ca
(OH) 2. It is a colorless crystal or white
powder and is obtained when calcium
oxide (called lime or quicklime) is mixed, or
"slaked" with water. It has many names
including hydrated lime, builders lime, slack
lime, cal, or pickling lime. It is of low
toxicity and finds many applications,
including for food. Because of its low
toxicity and the mildness of its basic
properties, it is widely used in the food
industry. But here in this experiment we
were studying the effects of this substance
on the crunchiness of the pickles. Time for
the mango to be soaked on the lime water
was varied; this is to determine the effect of
time of mango soaked in lime water and the
crunchiness of the pickles. From the result
obtain we found out that the mango that
soaked into the lime water for 1 hour more
crunchy followed by 30 minutes and 5
minutes. Alum may be safely used to firm
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KITCHEN CHEMISTRY PROJECT 2011
fermented pickles. However, it is
unnecessary and is not included in the
recipes. The calcium in lime definitely
improves pickle firmness. Food-
grade lime may be used as a lime-
water solution for soaking fresh mango
before pickling them. The calcium in the
lime reacts with the pectic acid in the fruit to
form calcium pectate, which adds to
'crunchiness'. There is already some calcium
pectate in mango and other vegetables. The
longer the time it was soaked, the
probability for the calcium in lime reacts
with pectic acid also high.
Excess lime absorbed by the mango
must be removed to make safe pickles. To
remove excess lime, drain the lime-
water solution, rinse, and then resoak the
mango in fresh water for 1 hour. Repeat the
rinsing and soaking steps two more times.
To further improve pickle firmness, the
mango pickles can be process for 30 minutes
in water at 180°F. This process also prevents
spoilage, but the water temperature should
not fall below 180°F. Use a candy or jelly
thermometer to check the water temperature.
But this process was not done for this time
experiment. But the crunchiness of the
pickles not only depends on this factors but
the concentration of the solution also affect.
In order to determine this we were observing
the crunchiest mango within the samples A,
B and C. Once we got the crunchiest one,
the comparison between the crunchiest 5
minute, 10 minute and 1 hour was made. We
found that the longer the mango soaked into
the lime water crunchier it will be.
Temperature
Temperature is one of the factors
affecting the pickling process. Pickling
process is also known as fermentation
process. The optimum temperature for
fermentation is around 21 oC. A change of
just a few degrees from this temperature
modifies the activity of the microbial
process and affects the quality of the final
product. Therefore, temperature control is
one of the most important factors in the
pickling process. A temperature of 18 oC to
22 oC is most appropriate for initiating
fermentation since this is the optimum
temperature range for the growth and
metabolism of L. mesenteroides.
Temperatures above 22 oC favor the growth
of Lactobacillus species. When temperature
is low, Leuconostoc
mesenteroides dominates, producing a mix
of acids, alcohol, and aroma compounds. At
higher temperatures Lactobacillus
plantarum dominates, which produces
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KITCHEN CHEMISTRY PROJECT 2011
primarily lactic acid. Many pickles start with
Leuconostoc, and change
to Lactobacillus with higher acidity.[
Otherwise, the temperature above 30 oC will provide pickles become too soft
during fermentation. It is also will cause the
excess of microbial growth in the pickle and
formation of bubble will occur. Actually,
bubbling in pickles is the feedback from
fermentation process. During fermentation,
cultures transform the fresh fruits into
pickles by converting sugars to lactic acid,
acetic acid, carbon dioxide, and other
beneficial substances. The bubbling formed
in pickles is the carbon dioxide that released
from fermentation process. To reduce the
excessive bubbling formed, pickles can store
under refrigerator to slow the fermentation.
A very low temperature makes process of
fermentation become more slowly compared
at room temperature. As we mentioned
above, the optimum temperature for
fermentation process is around 21 oC, hence
when pickles are kept in refrigerator which
is in very low temperature under 21oC, the
microbial process will become slow, and
process converting sugar to lactic acid and
carbon dioxide also become slow, this will
reduce the formation of bubbles in pickle.
There are some precaution steps during
making the pickles. Make sure that using the
different spoon to stir salt or sugar with
water and fruit in order to avoid pickles
from being contaminated. Furthermore, we
should use boiled water instead of pipe
water to make pickle. Do not use the pipe
water because there are microorganisms that
might be caused the growth of bad bacteria
and contaminate the pickles.
Concentration
Now, we move to the other factors
that make the pickles crunchier which is
concentration of the solution that the pickles
were soaked. There are four different of
concentration in making these pickles. The
four solutions that we prepared are:
1. Solution of water and sugar only
2. Solution of water and salt only
3. Solution of water, salt and sugar only
4. Solution of water, sugar and asam boi
only
All of the solutions have different
concentration. The lowest concentration is
the concentration of sugar solution (syrup),
the middle one is sugar and salt solution and
the highest concentration is the solution of
salt (brine). Based on the results, it showed
9
KITCHEN CHEMISTRY PROJECT 2011
that the solution of sugar give the most
crunchy texture compare to the other. This
means that the lowest the concentration of
pickling solution, the crunchy the pickles.
The process that involved to makes the food
more crispy was osmosis. Osmosis is the
movement of water molecules through a
selectively-permeable membrane. Water will
move from an area of high solute
concentration to an area of low solute
concentration. This process does not require
any energy so it occurs naturally and goes
on until equilibrium is achieved. This is the
essence of osmosis and is life critical in the
cells of all living organisms. All plants,
fruits consist of cells, surrounded by a cell
wall that gives strength to the plant. The
fluid in the cell is under pressure, providing
a crisp and fresh texture.
Osmosis
When pickling, water will be extracted from
the fruit by osmosis, resulting in a
concentration of solutes in the food product
and make the fruit less crispy or crunchy.
Meanwhile, diffusion will cause the fruit to
enrich itself with solutes in the brining
solution or syrup. It is also possible that
substances in the fruit leach out to the
brining solution.
Different concentrations contribute to
different texture of pickles. The
concentrated solution contains high amount
of solute which made the lots of water from
fruit to move out to the outer membrane.
When water from fruit move outs, it makes
the fruit less crunchy. For dilute solution,
the amount of water loss is less compare to
the concentrated solution and hence made
the fruit crispier. Thus, the dilute the
solution, the less amounts of water move out
from the fruit and the crunchier the pickles.
The effect can again be reversed by washing
the pickles afterwards in clean ice water.
Now the pickles will take up water since the
concentration of solutes is higher in the cells
than in the ice water.
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KITCHEN CHEMISTRY PROJECT 2011
Pickling will preserve food
microbiologically. It will actually make
water unavailable for any living organism in
the brine or brined food product. Since the
concentration of solutes is far greater outside
the cell of any bacteria or other harmful
organisms than inside (food’s cell), hence
the result is that bacteria will not be able to
uptake water, which is essential to remain
alive, on the contrary, water will be forced
out of the cell, causing the bacteria to
dehydrate and eventually die. The same
happens in a pickling solution, with added
pH effects.
In this kitchen project also, we add few
asam boi in 4th solution for better taste.
Asam boi is to make the pickles taste sourer.
It is quite tasty but not as tasty as the pickles
that was soaked in 3rd solution
CONCLUSION
The longer the mango is soaked into the
lime water the crunchier it will be. This is
because the calcium in the lime reacts with
the pectic acid in the fruit to form calcium
pectate, which adds to 'crunchiness'. When
concentration of solution increase, the
texture of mango pickled become crunchier
due to the process of osmosis. This process
occurs because of the tendency of substance
to move through membrane from high
concentration water molecule to low
concentration of water molecule. In this
case, water molecule inside mango flows out
to the solution since it has lower water
molecule concentration than the water
molecule concentration inside mango. The
flowing out of water molecule from mango
makes the pickled become crunchier.
REFERENCES
Retrieved October 20,2011,from
http://www.popsci.com/diy/article/200
9-05/how-make-quick-pickles
Peter S. Murano, understanding Food
Science and Technology, United States
of America, Thomson Learning, Inc.,
2003
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KITCHEN CHEMISTRY PROJECT 2011
Alev Bayindirli, Enzymes in Fruit and
vegetable Processing: Chemistry and
Engineering Application, United States
of America, Taylor & Francis Group,
2010
Retrieved October 22,2011,from
http://www.chemtutor.com/soluti
on.htm
http://water.me.vccs.edu/courses/
env211/lesson8_3.htm
http://www.mcvitamins.com/Healt
h%20Opponents/processed_foods
.htm
http://www.edvantia.org/products
/pdf/voices/Voices3=act2.pdf
http://www.edvantia.org/products
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http://chemistry.about.com/od/lec
turenotesl3/a/concentration.htm
Retrieved November 1,2011, from
http://en.wikipedia.org/wiki/Pickling#T
he_pickling_process
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