MODERN HIGHER

SECONDARY SCHOOL
MALAYNAGAR, DATTAPALLI
AGARTALA, WEST TRIPURA
SESSION : 2024-2025

A CHEMISTRY INVESTIGATORY PROJECT

TOPIC : Preparation of soybean milk and its

comparison with natural milk with respect to curd
formation, the effect of temperature, etc.

:Subhradeep Paul

Section :C
Roll no. : 55

UNDER THE GUIDANCE OF

TIRTHASALIL S IL SIR
CERTIFICATE

This is to certify that Subhradeep Paul, a student of Modern Higher

Secondary School of Class XII (Science) has successfully completed
the research on the Chemistry project,“Preparation of Soyabean
milk and its comparison with the Natural milk with respect to
Curd formation, effect of temperature, etc” under the guidance of
Mr Tirthasalil Sil, during the academic session 2024-2025 as per
guidance of Central Board of Secondary Education (CBSE).

Mr. Sujit Dasgupta (Principal)

SIGNATURE OF PRINCIPAL

SIGNATURE OF EXTERNAL EXAMINER SIGNATURE OF INTERNAL EXAMINER

ACKNOWLEDGEMENT

It gives me great pleasure to express my gratitude towards our

Chemistry Teacher – Tirthasalil Sil sir for his guidance, support and
encouragement throughout the duration of the project. Without his
motivation and help, the successful completion of this project would
have been difficult for me.
I would also like to thank Mr. Sujit Dasgupta, Principal of Modern
Higher Secondary School for his support and encouragement.
And last but not least, I want to thank my family members and friends
for their help and support.

Subhradeep Paul
XII-Science
Modern Higher Secondary School
 INDEX

S. No. Content Page no.

1 Certificate 1
2 Acknowledgement 2
3 Aim 4
4 Objective 5
5 Introduction 6
6 Theory 7
7 Requirements 8-9
8 Chemical Equations 10
9 Preparation 11
10 Procedure 12
11 Observation 13
12 Calculation 14
13 Result 15
14 Data Analysis 16
15 Health Benefits 17
16 Disadvantage 18
17 Conclusion 19
18 Bibliography 20

Teacher’s Signature
AIM

Preparation of soybean milk and its comparison with natural milk

with respect to curd formation, the effect of temperature, etc.
OBJECTIVES

1. To prepare soybean milk from dried soybeans.

2. To evaluate the curd formation of soybean milk compared to
natural milk.
3. To investigate the effect of temperature on curd formation.
4. To measure and compare the pH levels of the curds formed.
5. To assess sensory characteristics such as taste and texture.
INTRODUCTION

Natural milk is an Opaque white

fluid secreted by mammary
glands of female mammals. The
main constituent of natural milk
are proteins, carbohydrates,
minerals, vitamins, fats and
water and is complete balanced
diet in itself. Fresh milk is sweet
in taste however when it is kept
for a long time at a temperature
of 30- 37°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 of milk is
sufficient and temperature is around 36°C it forms Semi solid mass
called curd. Soyabean milk is made from Soya beans. It resemble
natural milk. The main constituents of soyabean milk are proteins,
carbohydrates, fats, Minerals and vitamins. It is prepared by Soya
beans dipped in water for some time the swollen soyabean is then
crushed into a paste.
THEORY

1. Curd Formation
Curd formation occurs through the coagulation of proteins, primarily
casein, facilitated by an acid or a starter culture.
2. Temperature Effects
The temperature during incubation affects bacterial activity,
influencing curd texture and flavour.
3. pH Measurement
The acidity of milk affects curd formation; lower pH values indicate
higher acidity, which aids in coagulation.
REQUIREMENTS

Materials Required
For Soyabean Milk:
a. Dried soybeans (100 g) b. Water (1 L)

c. Blender d. Cheesecloth
.

e. Pot for boiling f. Heat source

For Natural Milk:

a. Fresh cow’s milk (100 mL)
Other Materials:
a. Curd starter (yogurt or lemon juice) b. Thermometer

c. Measuring cylinder d. Beaker

e. pH strips f. Incubator or hot place

g. Stopwatch
CHEMICAL EQUATIONS

1. Coagulation Reaction
Milk Proteins (Casein) + Acid→ Curd (Coagulated Casein) + Whey
2. Preparation of Soybean Milk
Dried Soybeans + Water→ Soyabean Milk+ Okara (Pulp)

.
PREPARATION

1. Weigh 150g of raw

soybeans.
2. Clean the soybeans to
remove impurities like dust,
stones, and stalks.
3. Wash the soybeans with
clean water to remove any
remaining impurities.
4. Soak the soybeans in a jar
with a lid.
5. Use 1.5 times the water to
the amount of soybeans for
soaking.
6. After soaking for 6-8 hours, the soybeans will double in volume.
PROCEDURE

1. Soak 150g soybeans in water (1.5 times their volume) for 6-8 hours
until they double in size.
2. Drain and grind the soaked soybeans into a fine paste.
3. Mix the paste with 250mL of water, then filter through a muslin
cloth to extract soybean milk.
4. Boil the soybean milk for 5-10 minutes, then let it cool to room
temperature.
5. Compare the taste of soybean milk with buffalo milk.
6. Heat 50mL of buffalo milk in three beakers to 30°C, 40°C, and
50°C. Add ¼ teaspoon curd to each and leave for 8 hours. Observe the
curd formed.
7. Repeat the process with 50mL of soybean milk in three beakers at
the same temperatures. Observe curd formation.
8. Compare the curd quality between both types of milk across the
temperatures.
OBSERVATON

Type of Beaker Temperature Curd Quality Taste

Milk
1 30°C Dense, semi- Sour
Buffalo solid
2 40°C Watery Less sour
3 50°C Very watery Tasteless
1 30°C Almost dense Almost
Soybean sour
2 40°C Semi-solid, Sour
watery
3 50°C Very watery Tasteless

o
CALCULATIONS

Average Time for Curd Formation

• Soybean Milk: (5+6+8)/3 = 6.33 hours
• Buffalo Milk: (3+4+6)/3 = 4.33 hours
Average pH Levels
• Soybean Milk: (6.0+6.2+6.5)/3 = 6.23
• Buffalo Milk: (4.6+4.5+4.8)/3 = 4.67
RESULTS

1. Buffalo milk forms better curd at 30°C-33°C.

2. Soybean milk forms better curd at 35°C-40°C.
DATA ANALYSIS

Criteria Buffalo Milk Soybean Milk

Source Cow or buffalo Soybeans
Lactose Contains lactose Lactose-free
Vegan No Yes
Protein 3.22g 3.27g
Carbohydrates 5.26g 6.28g
Fat 3.25g 1.00g
Calcium 113mg (11%) 25mg (3%)
Magnesium 10mg (3%) 25mg (7%)
Vitamin B1 0.044mg (4%) 0.060mg (5%)
(Thiamine)
Fat Composition Higher saturated fat Lower saturated fat
Potassium 143mg (3%) 118mg (3%)
Sodium 43mg (3%) 51mg (3%)
HEALTH BENEFITS

There are a number of health benefits with drinking Soya milk. These
are as follows:
1. Heart Health: Soybean milk
can help lower bad cholesterol
and raise good cholesterol, which
is good for your heart.
2. Weight Control: It is low in
calories and high in protein,
helping you feel full and aiding in
weight loss.
3. Strong Bones: With calcium
and magnesium, soybean milk
supports strong bones and can
help prevent bone diseases.
4. Hormonal Balance: It contains natural compounds that may help
balance hormones, especially during menopause.
5. Cancer Protection: Drinking soybean milk may lower the risk of
certain cancers, like prostate and breast cancer.
6. Digestive Health: Being lactose-free, it is easy on the stomach and
helps with digestion for those who are lactose intolerant.
7. Healthy Skin: The antioxidants in soybean milk can improve skin
health and reduce signs of aging.
DISADVANTAGES

Soybean milk is healthy, but it has

some downsides. First, it contains
phytoestrogens, which can mimic
estrogen. This may affect male fertility
and cause hormonal imbalances in
women.
It can also lead to digestive issues, like
gas and bloating, especially for those
not used to soy. Additionally, soybean
milk has phytates, which can reduce
the absorption of essential minerals like calcium and iron.
Some people may be allergic to soy, experiencing reactions such as
rashes or stomach pain. Lastly, many store-bought versions have
added sugars and preservatives that can lessen their health benefits.
In conclusion, while soybean milk is nutritious, it’s important to
consider these disadvantages when choosing it as a part of your diet.
CONCLUSION

This project shows that both soybean milk and buffalo milk are good
sources of nutrition, but they have different characteristics. Buffalo
milk curdled faster and formed a firmer texture due to its higher
lactose content. In contrast, soybean milk needed higher temperatures
and more time to form curd. However, soybean milk is a great
lactose-free option, rich in protein, making it suitable for people with
dietary restrictions. Both types of milk can be included in a healthy
diet, with soybean milk being a valuable choice for vegans and those
who are lactose intolerant. Overall, understanding the differences and
benefits of these milk types is important for making informed dietary
choices.
BIBLIOGRAPHY

1. William Shurtleff : “Tofu and Soymilk Production”.

2. Farrah J. : “Soy Milk and Raw Honey”.
3. Wikipedia : http://www.wikipedia.org
THANK YOU