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1. INTRODUCTION

Natural milk is an opaque white fluid.
Secreted by the mammary gland of female
mammals. The main constituent of natural
milk are proteins, carbohydrates, minerals,
vitamins, fats and water and is a complete
balanced diet in itself fresh milk is sweetish
in taste. However, when it is kept for a long
time at a temperature of 35 + 5°C it
becomes sour because of bacteria present
in air. These bacteria convert lactose of milk
into lactic acid which is sour in taste. In
acidic conditions casein of milk starts
separating out as precipitate. When the
acidity in milk is sufficient and temperature
is around 36°C, it forms semi solid mass,
called curd. Soybean milk is made from
Soybeans. It resembles natural milk. The
main constituents of Soybean milk are
proteins, carbohydrates fats, minerals and
vitamins. It is prepared by keeping
Soybeans dipped in water for some time.
The swollen Soybeans are then crushed to
a paste which is then mixed with water. The
solution is filtered. And the filtered white
liquid is the soybean milk.

2. SOYBEAN MILK
NATURAL MILK

3. AIM
Preparation of Soybean milk, and it's
comparison with natural milk with respect
to curd formation, the effect of temperature
etc.
REQUIREMENT 1.Beakers
2.Pestle and mortar.
3.Measuring cylinder
4.Glass rod
5.Tripod stand
6.Thermometer
7.Muslin cloth
8.Burner
9.Soybeans
10.Buffalo milk or Cow milk
11.Fresh curd
12.Distilled water

4. THEORY
PREPARATION OF SOY
CURD(YOGHURT)
Soy yogurtfl (Soya yoghurt in British English)
also referred to as Soygurt or Yofu (a
portmanteau of yoghurt and tofu)fl is yogurt
prepared using soy milkfl yogurt bacteriafl
mainly Lactobacillus bulgaricus and
Streptococcus thermophilus and sometimes
additional sweetener like fructose glucose or
raw sugar. It is suitable for vegans as the
bacteria for shop-bought soy yogurt are usually
not grown on a dairy base. Soy yogurt can be
prepared at home using the same method as
dairy yogurt. One tablespoon of sugar per 1 litre
of unsweetened soy milk may be added to
promote bacterial fermentation,Soy milk on its
own lacks the lactose (milk sugar) that is the
basic food for the yogurt bacteria.Soy yogurt
may have a slight beany soy taste when made
directly from freshly prepared soymilk but this is
less pronounced in shop- bought soy yogurt
and in soy yogurt made from commercial soy
milk. Soy yogurt contains less fat than yogurt
made with whole milk. This amounts to about
2.7% (the same percentage as soy milk)versus
3.5% in dairy yogurt. However dairy yogurt can
be made with 2% to 1% or fat- free milk and
these cases it is lower in fat than soy yogurt.

5. PREPARATION OF NATURAL
CURD(YOUGHURT)
Buffalo curd (in Hindi "DahI") is a traditional and
a nutritious dairy product. It is prepared by
buffalo or cow milk and it is popular throughout
the south Asian countries such as India. etc.
Buffalo milk is traditionally better than cow milk
for curd due to its higher fat content making a
thicker curd. Mostly clay pots are used as
packaging material for Buffalo curd. Buffalo
curds is obtained by curdling (coagulating)
buffalo milk using microbial activities. In this
process lactose in buffalo milk is converted in to
lactic acid using several micro-organisms.
Several microorganism species are involved in
the fermentation such as Streptococcus
thermophiles.Buffalo curd has a higher
nutritional value of protein fat lactose minerals
and vitamins. It should have 7.5% of milk fat
8.5% of milk. solids and 4.5% of Milk acid (lactic
acid). Quality of the curd is totally depending on
the starter culture. Fermentation also develops
the characteristic flavour and colour of the
product. Traditionally buffalo milk is filtered and
boiled the scum is removed and it is cooled to
room temperature. A few spoonful of a previous
batch of curd are added and it is then mixed
well and poured into clay pots. These are
sealed by wrapping a piece of paper over the
pot and allowing it to stand for 12 hours.

6. PROCEDURE
1.Soak about 150g of Soybeans in different
amount of water so that they are completely
dipped in it. Keep them dipped for 24 hours.
2.Take out swollen Soybeans and grind them
to a very fine paste with pestle and mortar.
3.Add about 250ml of water to this paste and
filter it through a muslin cloth. Clear white
filtrate is Soybean milk. Compare its taste
with buffalo milk.
4.Take 50ml of Buffalo milk in three beakers
and heat the beakers to 30°C, 40°C and 50°
C respectively. Add 1/4 spoonful curd to each
of the beakers. Leave the beakers
undisturbed for 8 hours and curd is formed.

SOYBEAN MILK CURD
NATURAL MILK CURD

7. OBSERVATION
RESULT
For buffalo milk, the best temperature for
formation of good quality and tasty curd is
30-33°C and for Soybean milk, it is 35-40°C
AT AT

AT AT AT AT

8. NUTRITIONAL
COMPARISION

9. NATURAL MILK V/S SOY
MILK


A cup of cow's or buffalo's milk contains
lactose(a sugar found only in milk), proteins,
carbohydrates, fats and calcium which are
also present in soy milk but in varying
quantities.

Lactose can be hard to digest by some
people i.e lactose intolerant or they lack the
required digestive enzyme lactase and will
not be able to digest milk easily. Soy milk is
mostly used as an alternative to milk used
by people with lactose intolerance since it is
completely lactose free.
NUTRITION

10. HEALTH BENEFITS OF
SOY MILK
• Improves lipid profile.
• Strengthen blood vessel integrity.
• Promote weight loss.
• Prevents post-menopausal syndromes.
• Prevent prostate cancer.
• Prevents Osteoporosis.
• Soy protein reduces the level of LDL (bad
cholesterol) and increases the level of HDL
(good cholesterol) in our body.
DISADVANTAGESSoy milk contains high percentage of
phytoestrogens, which may decrease fertility
in men if they consume more than 3 quarts
per day. Too much estrogen can also cause
hormone imbalance in women when
consumed too much and also has difficulty
breaking down. Consuming these simple
sugars can cause some people to
experience lot of gas. Soy milk also contains
substances called phytates which interfere
with calcium absorption.

11. CONCLUSION
●Both natural milk and soya milk have
almost same constituents except the
presence of lactose in natural milk. Soya
milk can easily be used as an effective
alternative for people whose diet is lactose
free. But on the other hand natural milk
curd requires lesser time (as per my
hypothesis taken earlier) than soya milk
curd also requires and room temperature
for its formation whereas soya milk curd
requires temperature slightly greater than
room temperature

12. BIBLIOGRAPHY
www.wikipedia.comwww.slideshare.comwww.google.com