INTERNSHIP REPORT

KHADAM MILK FOODS

SAHIWAL

BY

HUZAIFA REHMAN

2020-GCUF-096243

DEPARTMENT OF FOOD SCIENCE

GOVERNMENT COLLEGE UNIVERSITY FAISALABAD

SAHIWAL CAMPUS

PAKISTAN

2024
 INTERNSHIP REPORT

KHADAM MILK FOODS

SAHIWAL

BY

HUZAIFA REHMAN

2020-GCUF-096243
An Internship Report submitted in partial fulfilment of the requirements for the degree of

BS FOOD SCIENCE AND TECHNOLOGY

DEPARTMENT OF FOOD SCIENCE

GOVERNMENT COLLEGE UNIVERSITY FAISALABAD

SAHIWAL CAMPUS

PAKISTAN

2024
 CERTIFICATION
This is to certify that the internship report work presented herein at “Khadam Milk
Food Sahiwal” submitted by Huzaifa Rehman, Reg. No. 2020-GCUF-096243 for
the award of Bachelor of Science in Food Science and Technology at Department of
Food Sciences, Government College University Faisalabad, Sahiwal Campus is based
on the working exposure at industry level carried out by her, under my guidance and
supervision during the academic session 2020-2024.

Prof. Dr. Nuzhat Huma

Head of Department

i
 DECLARATION
I, Huzaifa Rehman, solemnly declare that this internship report at “Khadam Milk
Food Sahiwal” is of my personal working efforts and no part has been copied from
any published source. I further declare that this work has not been submitted for
award of degree. The university may take action if the above statement is found
sinaccurate at any usage.

Huzaifa Rehman
2020-GCUF-096243

ii
 DEDICATION
Internship at Khadam Milk Foods (Sahiwal) was an attempt to seek experience of
the corporate lifestyle of a successful growing company. First of all I am thanks to
ALMIGHTY ALLAH and Beloved Holy Prophet Hazrat MUHAMMAD
(S.A.W.W) who give me a pathway for learning. I want to dedicate my all efforts and
success to my loving parents and siblings. I also dedicate this report to my teachers
and friends who helped me for my success at every step of my life. After them I
dedicate this report to my parents who believe on my strength and hard-working
ability and allow me to travel on that road. I hope people and upcoming students will
find this report useful and this will adds to their knowledge. Keep your dreams alive.
Understand to achieve anything requires faith and belief in yourself, vision, hard
work, determination and dedication. During my two month internship, I was
committed to making the most of the experience and contributing to the success of the
organization.

iii
 ACKNOWLEDGEMENT
First and foremost, we would like to express our gratitude to ALLAH (SWT) for His
blessings, without which we would not have been able to conduct and complete any
task. The blessings of ALLAH ALMIGHTY are innumerable. Nothing can occur
without Allah's permission, and everyone in the universe is responsible to him. Rather
than trying to think of reasons to express our gratitude to him, we should instead be
appreciative and keep doing so. Many thanks to the Holy Prophet Hazrat
Muhammad (PBUH), whose teachings are the best way for us to succeed in both of
our lives, in this world and the hereafter. Without mentioning the people in our
community who were integral to the completion of this report, it would not be fair to
present it. Thanks to all my teachers including Head of Department Prof. Dr. Nuzhat
Huma, Supervisor Madam Samra Khan, Dr. Saeed Uddin, Mr. Obaid-ul-Hassan,
Dr. Sibt-e-Abbas, Dr. Sajid Manzoor, Dr. Sabiha Abbas, Madam Arooj Fatima,
Madam Muneeza, Madam Zartasha Siddique, Madam Bushra Farooq, Madam
Ayesha Khalil, Sir Saud Shabir, Madam Mehak Ali, Madam Mubashra Niaz,
Mr. Kamran Ashraf, Mr. Hafiz Muhammad Junaid Saqib, Madam Umme-
Ruqiya and Madam Areeba Yaqoob, special thanks to Mr. Liaqat Ali Sajid (Lab
Attendant) at department of Food Sciences in Govt. College University Faisalabad
(Sahiwal Campus). I would like to express my gratitude to my supervisor, Shah Zaib
sb (Quality Assurance Manager), who provided me with valuable guidance and
feedback throughout my internship. I am also grateful to my parents and family for
their unwavering love and support, which has been instrumental in my success. I
would also like to thank my sisters, who have been my confidantes and friends
throughout my life. Their companionship and support have been invaluable in helping
me navigate the ups and downs of life. Lastly, I would like to acknowledge the
contributions of my friends, who have been there for me through thick and thin.
Finally, I am grateful to my professors who have equipped me with the knowledge
and skills necessary to succeed in my field. Thank you all for your support and
encouragement. Thank you all for your love and support.

Huzaifa Rehman

iv
 EXECUTIVE SUMMARY
Haji Khadam Hussain (Late)" got an idea of starting a venture related to Desi Ghee.
"New Sohail Dairies" is an established and registered firm since 1956. It was set up
by Mr. Haji Khadam Hussain (Late)". This business is the result of almost half
century experience, research in dairy and its products. We are working under the
brand "Khadam's Desi Ghee", "Khadam's Butter" and "Fresh Cream". Our products
especially "Desi Ghee" and "Butter" are available in almost all types of famous
bakeries, chain stores and super stores all over the Pakistan. The Khadam Milk Foods
is committed to supplying quality products and excellent customer services to its loyal
customers and through its innovativeness continues to diversify its range of products
and keep barest with latest technological change. The company shall continue to build
strong customer relations and sell products at competitive price, thereby impacting
positively on the economy of the nation, improve employee’s welfare, and continue to
meet its obligation. Different qualitative milk test (Milk Fat, SNF, COB, APT,
Acidity of Milk and different adulteration test etc) are performed by Khadam Milk
Foods. Cream is also tested by quality control department such as Fat, Moisture, FFA,
Glucose test and Reichart Meissl test of cream performed by the quality control
department. Then cream is transfer to butter section and butter is converting into the
butter by churning, then end product is transferred to packaging section.
Microbiological testing also done by Khadam Milk Foods, such as microbiological
tests (TPC, Coliforms, Salmonella, Shigella, Yeast & Mould & Escherichia coli etc).

v
 TABLE OF CONTENTS
Sr. No. Contents Page No.

1. Introduction 01

2. List of Products and Explanation 04

3. Processing of Milk Products 08

4. Test performed at Reception Lab 27

5. Adulteration Test 38
6. Microbial Test 43
7. Plant Sanitation 47
8. Learning outcomes 49

Conclusion 50

vi
1. INTRODUCTION
The main objective of industry is the supply of pure and consumer satisfactory food.
That is according to the demand of customer and during production they will try their
best to fulfil all the standard requirements. No compromise on quality. Industry
perpetrated to supplying quality products and excellent customer services to its loyal
customers and through its innovativeness continues to diversify its range of products
and keep barest with latest technological change. The company shall try their best to
connect strong customer relations and sell products at competitive price, thereby
impacting on nation economy and also improve employee welfare and continue to
meet responsibilities. Our objective is to enhance our knowledge and completely
understand processing rules, procedure and their strategies and also to know about
how to implement these strategies to obtain desire products that are according to
customer demands and to understand about how to maintain quality. To know about
techniques that are helpful in solving problems that we face during processing and
also issues that we faces in maintaining quality of products during and after
processing. Quality Assurance is kept in mind when manufacturing products. All
products adhere to Pakistan Government export quality requirements and are
manufactured under strict Total Quality Assurance programs. All products adhere to
Pakistan Government export quality requirements and are manufactured under strict
Total Quality Assurance programs.
History
Earlier "Desi Ghee" was made at home, but quality and quantity were detrimental
factors, seeing this "Haji Khadam Hussain (Late)" got an idea of starting a venture
related to Desi Ghee. M/S "New Sohail Dairies" is an established and registered firm
since 1956. It is an inherited business managed by next generation. It was set up by
Mr. Haji Khadam Hussain (Late)" This business is the result of almost half century
experience, research in dairy and its products. We are working under the brand
"Khadam's Desi Ghee", "Khadam's Butter" and "Fresh Cream". Our products
especially "Desi Ghee" and "Butter" are available in almost all types of famous
bakeries, chain stores and super stores all over the Pakistan. To complete the whole
process we have in our mind the concept of "SAFE and HALAL FOODS"

1
Location
The production facilities are located at 152-153/A Small Industrial Estate Sahiwal.
Objectives
Mission Statement
“Purity, Customer Satisfaction, No Compromise on Quality”
The company is committed to supplying
quality products and excellent customer
services to its loyal customers and
through its innovativeness continues to
diversify its range of products and keep
barest with latest technological change.
The company shall continue to build
strong customer relations and sell products at competitive price, thereby impacting
positively on the economy of the nation, improve employee’s welfare, and continue to
meet its obligation.
Vision Statement
The Company is committed to be marker leader in the world for milk and milk
products, and to be the benchmark company in the industry of the world.
Quality Policy
The company is committed to excellence in all areas of operation and continuous
Improvement in the provision of the highest quality product that meet the customer
expectations as well as legal and safety standards for health requirement.
Today’s consumers of dairy products want to know that the food they eat is safe and
wholesome. Technology and scientific understanding is used to guide and monitor
and control for producing products that are as nutritious, safe, and wholesome to
consume.
Transportation
We have our own transportation system for collection and supplying to distributors
and institutions. We also have contracts with well-known courier cargo services of
Pakistan.
 Firm to Consumer
 Firm to distributor to Retailer to Consumer
 Firm to institutes

2
 Firm on Direct Export
Quality Control
Company has QA/QC section to maintain quality as well as to develop Products as
per its corporate client’s requirements. For this purpose we have a well-developed and
well equipped Laboratory.
Current Certification
 Certification of Halal Authentication
 Certificate of Halal (JMUIMP)
 ISO 9001:2008 Certified
 ISO 22000-2005 Certified
 License for use of Pakistan Standard Mark (PSQCA)
 Certificate of Punjab Food Authority (Food Business License)

3
2. LIST OF PRODUCTS AND EXPLANATION
Khadam Milk Foods have different variety of food products like Cheese, Desi Ghee
and Butter. Following are the products discussed in detail.
Products
The quality dairy products of Khadam Milk Foods are:
 Khadam Desi Ghee
 Khadam Butter
 Khadam Cheddar Cheese
 Khadam Mozzarella Cheese
Innovations
 Khadam Pizza Cheese
 Khadam Cottage Cheese
Milk and its Composition
Introduction of Milk
Milk is a nutrient-rich liquid food produced by the mammary glands of mammals. It is
the primary source of nutrition for young mammals, including breast-feed human
infants before they are able to digest solid food.
Early lactation milk is called colostrum, which
contains antibodies that strengthen the immune
system and thus reduces the risk of many
diseases.
Definition
Standard definition of milk is a lacteal secretion which is
 Practically free from the colostrum
 Obtained from complete milking of one or more cow(s)
 Should contain not less than 8.25 % SNF (Solid Not Fat) and 3.25% Fat
Pasteurization
 The usable life of milk can be extended for several days through techniques
such as cooling (which is the factor most likely to influence the quality of raw
milk) or fermentation
 Pasteurization is a heat treatment process that extends the usable life of milk
and reduces the numbers of possible pathogenic microorganisms to levels at
which they do not represent a significant health hazard

4
Composition of Milk
Whole cow's milk contains about 87% water. The remaining 13% contains protein,
fat, carbohydrates, vitamins, and minerals. The milk composition are:
 Carbohydrates (lactose)
 Fat
 Protein
 Vitamin and minerals
Water
Water is major constituent of milk as it constitute more than 80% of whole milk. The
amount of water in milk is regulated by the amount of lactose synthesized by the
secretary cells of the mammary gland. The water that goes into the milk is delivered
to the mammary gland by the blood. Milk production is very rapidly affected by a
shortage of water and drops the same day drinking water is limited or unavailable.
Carbohydrates
The principal carbohydrate in milk is lactose. The concentration of lactose in the milk
is relatively constant and averages about 5% (4.8-5.2%). As opposed to the
concentration of fat in milk, lactose concentration is similar in all dairy breeds and
cannot be altered easily by feeding practices.
Proteins
Milk protein is very exclusive in nature and it is the natural source of amino acids.
More than 95 amino acids of total declared amino acids are available in the milk
protein. Milk protein is regarded as high resource and matchless resource of amino
acids. Particularly it contains many essentials amino acids which are not synthesized
in our body and required for normal metabolism. The concentration of protein in milk
varies from 3.0 to 4.0%. The percentage varies with the breed of the cow and in
proportion to the amount of fat in the milk The protein falls into two major groups:
caseins (80%) and whey proteins (20%). Casein is present in the suspicion / colloidal
form in the milk.
Fat
Fat in milk refers to the natural lipid content present in milk. It is an essential
component that contributes to the taste, texture and nutritional value of milk.
Normally, fat (or lipid) makes up from 3.5 to 6.0% of milk, varying between breeds of
cattle and with feeding practices. Fat is present in milk in small globules suspended in

5
water. Each globule is surrounded by a layer of phospholipids, which prevents the
globules from clumping together by repelling other fat globules and attracting water.
As long as this structure is intact, the milk fat remains as an emulsion. The majority of
milk fat is in the form of triglycerides formed by the linking of glycerol and fatty
acids.
Minerals and Vitamins
Different minerals found in milk are potassium, calcium, chloride, phosphorus,
sodium, magnesium and small amounts of trace minerals. The digestibility of
calcium and phosphorus are unusually high, in part because they are found in
association with the casein of the milk. Vitamin A, D, E, K, C and B complex are
also found in milk.
Composition of Milk
Constituents Cow Milk (%) Buffalo Milk (%)

Water 86.50 83.18

Fat 4.39 6.71

Protein 3.30 4.52

Lactose 4.44 4.45

Total Solids 13.0 16.82

Solids Not Fat 9.11 10.11

Ash 0.73 0.80

Calcium 0.12 0.18

Magnesium 0.01 0.02

Sodium 0.05 0.04

Potassium 0.15 0.11

6
Milk Economy in Pakistan
 Pakistan is the sixth most populous country in the world with an estimated
population of over 160 million, growing at a rate of more than 1.8 percent per
annum. Agriculture, being the mainstay of the economy, generates 20.9 percent of
the total GDP and employs 43.4 percent of the total workforce
 Pakistan is the 5th largest producer of milk in the world, its industry volume of
dairy products reached at US$26 billion in rural and urban areas on the increasing
population and domestic local consumption however the total milk production is
not fulfilling domestic human needs (Ameen, 2012)
 With an almost 50 percent contribution, livestock is by far the most important
subsector in agriculture
 In the past ten years, the subsector grew by an average of 5.8 percent. The share of
livestock in agriculture growth jumped from 25.3 percent in 1996 to 49.6 percent
in 2006
 Despite decades of oversight by the Government, Pakistan is the fifth-largest milk
producer in the world

7
3. PROCESSING OF MILK PRODUCTS
Desi Ghee
 Ghee, which is widely used in Pakistan cooking, is the pure butter fat left over
after the milk solids and water are removed from butter
 Ghee is nutritionally rich class of clarified butter used as a cooking medium.
 It is known for its taste & pure health in the Indian
subcontinent
 It is commonly used in South Asian and Middle
Eastern cuisines, traditional medicines, and religious
rituals
 It is prepared by gently heating butter, and retaining
the clear liquid fat while discarding the solid residue that settled to the bottom
 The taste, texture, and colour of the ghee depend on the quality of butter, source of
milk, and duration of boiling
 In Ayurveda, ghee is considered as a vital medicine for healing wounds,
improving digestion, reducing free radicals, and boosting immune system
 It can be kept at room temperature for several weeks without refrigeration
 The consumption of ghee has increased, as it is rich in fat soluble vitamins A, D,
& E, helps in building strong bones, improves digestion, and reduces
inflammation. It also helps to nourish the skin from within, offering a natural
glow and radiance. Furthermore, its anti-bacterial properties make it ideal for
treating minor wounds and cuts
 However, overconsumption of ghee could lead to cardiovascular diseases, which
in turn is key factor affecting the market growth during the forecast period
Nutritional Facts
Ghee or clarified butter is sometimes used as an alternative to regular cooking oil.
Ghee is 99.9% fat and 1% moisture along with some fat-soluble vitamins, charred
milk protein fractions among others
Saturated fat makes up the majority of the fat in ghee. Additionally, it has cholesterol.
If the ghee comes from milk from grass-fed cows, it is also high in vitamins A, E, and
K. It also has butyric acid

8
Composition of Desi Ghee
Constituents Cow Milk Ghee Buffalo Milk Ghee

Fat (%) 99-99.5 99-99.5

Moisture (%) <0.5 <0.5

Carotene (mg/g) 3.2-7.4 -

Vitamins A (IU/g) 19-34 17-38

Cholesterol (mg/100g) 302-362 209-312

Free fatty acid (%) 2.8 2.8

Processing Steps of Desi Ghee

Raw Milk Filteration Cream

Chilling
Reception Separation

Culturing, Churning of
Pasteurization
Aging, Cream to
(CCP)
Crystallization Butter

Separation of
Washing of Melting of Clarification of
Whey and
Butter Butter Ghee
Ghee

Filling in
Cooling
Container

9
Manufacturing Steps of Desi Ghee
Raw Milk Reception
 Firstly the raw milk is collected
 Then organoleptic test and milk analysis
test are performed to check the quality of
milk
Cream Separation
 Cream is separated from the milk. The
cream should be sweet, pH greater than
6.6, not rancid a free from off flavors
Pasteurization
 Pasteurization is usually done at 82-88C
or more
 The high temperature is needed to destroy
enzymes and microorganisms that would
impair the keeping quality of butter
Culturing, Aging, Crystallization
 Mixed cultures of streptococci Cremoris,
streptococci lactis, and Streptococci
diacetyl lactis are used
 In aging tank, cream is subjected to a
program of controlled cooling that keeps to
give the fat required crystalline structure
 The optimum temp. for this condition is
usually 5-10C and time requirement is 12-
15 hours
Churning of Cream to Butter
 In the churning process, the cream is
violently agitated for 5-10 min. to break
down the fat globules causing the fat to
coagulate into butter grains, while fat
contents of the remaining liquid
(buttermilk) decreases

10
 Optimum temp. for churning is 9-11C
Washing of Butter
 In washing process, all buttermilk is
washed out of the butter
 Otherwise the butter would not keep and
go rancid
Melting of Butter
 To make ghee, the process start with the
simmering butter “between” 105-117C
to evaporate the water
 The temp. is then elevated to above
130C so that the lactose, casein and the
whey protein experience the Millard
reaction
Separation of Whey and Ghee
 Once the butter has completely melted it
will bubble and began to separate
 As the butter simmers some of the milk
proteins rise and sit on the surface as it
separate from the fat and water
 White solids are discarded from the
surface. This process takes time for the butter oil to turn clear
Cooling
Allow the ghee to cool slightly for about 3-5 minutes and stored at room temp. for up
to 3 month or refrigerated for 1 year
Uses of Desi Ghee
 Strengthens immunity and helps in bone development: As kids, we were given a
spoonful of Desi ghee daily to boost our immunity and make our bones strong
 Desi ghee acts as a strong microbial, anti-cancer and antiviral agent
 It is a rich source of fat soluble vitamins that help in growth and development of
the bones
 Ghee or clarified butter is sometimes used as an alternative to regular cooking oil
 Rich in anti-oxidant so it can protect our body from free radicle damage
 Promote memory retention and good for people suffering from joint pain

11
 Ghee is a rich source of vitamin A, D, E & K that
is important in ensuring normal cellular function
and growth in humans
 Ghee is a rich source of antioxidants, it also serves
as an immunity booster for it prevents the
generation of free radicals in our bodies that gives
way to chronic health conditions like cardiac
disorders, inflammatory disease, cataract and
several other diseases
Application
 Ghee is perfect for frying, roasting, and sauteing meats, fish, veggies, and eggs
 You can use ghee as a condiment on a baked potato or roasted squash. Ghee can
be used like butter on bread and bagels
 It can also be used in place of butter or oil for baking
Butter
 Butter is a dairy product made by churning
cream or milk
 It can be used like a spread and as a regular
ingredient in cooking
 From a nutritional perspective, butter is a
very good source of protein
 It contains saturated fat made from the fresh cream and milk
 Butter is one of the vital ingredients of confectionary products
 Butter is a water-in-oil emulsion resulting from an inversion of cream, where the
milk protein are the emulsifier
 Butter remains a firm solid when refrigerate but soften to a spreadable consistency
at room temperature, and melt to a thin liquid consistency at 32-35C
 It generally has a pale yellow colour but varies from deep yellow to nearly white.
 However, with the dropping prices of butter, the competition between substitute
products has intensified
 The demand for spreadable butter has been growing gradually in developing
countries, as it is used in various food products

12
 The raw material for the production of butter is cow’s milk, which, depending on
the breed to which the cow belongs, contains from about 3-6%. Butter can also be
made from buffalo milk, as well as from goat’s milk which is considered the most
beautiful or sheep’s
Composition of Butter
Components Percentage (%)

Moisture 15.5-16

Protein 1

Fat 80-83

Carbohydrate 0.5

Vitamins (A, D) 0.5

Minerals (Sodium) 2

Processing line of Butter

Raw Milk Cream

Filteration Chilling
Reception Separation

Culturing, Churning of
Pasteurization Washing of
Aging, Cream to
(CCP) Butter
Crystallization Butter

Cooling Packing

13
Manufacturing Steps of Butter
Raw Milk Reception
 Firstly the raw milk is collected
 Then organoleptic test and milk analysis
test are performed to check the quality of
milk
Cream Separation
 Cream is separated from the milk
 The cream should be sweet, pH greater
than 6.6, not rancid a free from off flavors
Pasteurization
 Pasteurization is usually done at 82-88C or more
 The high temp. is needed to destroy enzymes and microorganisms that would
impair the keeping quality of butter
Culturing, Aging, Crystallization
 Mixed cultures of streptococci Cremoris, streptococci lactis, streptococci diacetyl
lactis are used
 In aging tank, cream is subjected to a program of controlled cooling that keeps to
give the fat required crystalline structure
 The optimum temperature for this condition is usually 5-10C and time
requirement is 12-15 hours
Churning of Cream to Butter
 In the churning process, the cream is
violently agitated for 5-10 min. to break
down the fat globules causing the fat to
coagulate into butter grains, while fat
contents of the remaining liquid
(buttermilk) decreases
 Optimum temp. for churning is 9-11C
Washing of Butter
In washing process, all buttermilk is washed
out of the butter. Otherwise the butter would
not keep and go rancid

14
Cooling and Packaging
After the processing, Butter is come in the packaging section. Then store the butter
less than -20C
Uses of Butter
 Due to its high concentration of fat, butter has a rich flavor and creamy texture
 It works especially well for high-heat cooking like pan-frying and can help
prevent sticking while adding flavor
 Butter is also widely used in baking to add texture and volume to baked goods and
desserts
 As it’s mainly composed of fat, butter is a high-calorie food. One tablespoon (14
grams) of butter packs about 100 calories, which is similar to 1 medium-
sized banana
 It can help lower chances of cancer. Butter is high in beta-carotene a compound
that body converts into vitamin A
 It can helps to strengthen bones. Butter contains vitamin D that is a vital nutrients
for bone growth and development
Cheddar Cheese
 Cheddar cheese commonly known as just cheddar is relatively hard, off white,
Sharp tasting, natural cheese
 Worldwide, Cheddar has it origin in Somerset in England were it has been
produced since the middle ages
 The cheese has most likely got its name from the town of Cheddar where
originally caves were used to store the cheese during ripening (British Cheese
Board, 2013)
 Cheese is a great source of calcium,
fat, and protein. It also contains high
amounts of vitamins A and B12,
along with zinc, phosphorus, and
riboflavin. In addition to the wealth
of micronutrients, Cheddar is also one of the best dietary protein sources
 Compared to food such as sugar, refined carbs, or even other dairy options like
butter, cheese is an excellent source of nutrition

15
 The caves provided a very good environment for the maturation of the cheese due
to the caves humidity and its constant temperature
 Nowadays cheddar cheese is produced not only in England but in most parts of
the world and the manufacturing technique of the cheese has developed a lot since
the production of the early cheeses from the 12 century
 The purpose of this study is to define the main characteristics of cheddar cheese,
describe the modern process line of this kind of cheese and also describe how the
different unit operations in the process affect the quality of the final product
 The report also aims to identify and discuss the critical control points of the
product line of cheddar cheese with respect to both the safety and the quality of
the product
 It is a firm cow’s milk cheese that ranges in flavor from mild to sharp and in color
from a natural white to pumpkin orange
 Cheddar cheese consist of high concentration of essential nutrients in particular
high quality protein and calcium which are great for the health
 It is a type of hard cheese with a sharp or acidic taste. Cheddar cheese is often off-
white in color
 Country of Origin: UK, England
 Source of Milk: Cow
 Pasteurized: Frequently
 Texture: Hard
 Aging time: 3-24 months (depending on variety)
Characteristics of Cheddar Cheese
 Cheddar cheese were traditionally produced as large cylindrical shaped loafs with
a weight of around 30 kg but nowadays in the modern industrial process the
cheese is instead formed into rectangular blocks to facilitate the handling of the
cheese
 According to its standard of identity, Cheddar cheese is required to have a
minimum of 50% fat content and a maximum of 39% moisture content
 Cheddar cheese is rennet coagulated and will require up to two years of aging
before consumption
 Cheddar is a ripened cheese that consists of approximately 55% of moisture on a
fat free basis (MFFB) which classifies the cheddar as a hard cheese

16
 There are many factors that affect the consistency of the cheddar cheese. Two of
these factors are the production steps of cheddaring and the addition of salt to the
cheese curd before the cheese is pressed
 The cheddaring affects the structure of the cheese by making the closed structure
of the cheese more enhanced due to the removal of entrapped air from the cheese
 The addition of salt to the cheese curd on the other hand affect the consistency of
the cheese as the salt content has an impact on the firmness of the cheese
 The salt content in a cheddar cheese should be between 1,75-1,95% as a
lower salt content gives the cheese too soft consistency whereas a higher salt
content gives the cheese too hard consistency
 The pH is also a parameter that has a clear effect on the texture of the cheddar
cheese
 Traditional cheddar has a pH of around 4.9
 The higher the pH the softer the texture of the cheese becomes
 The taste of cheddar develops during the ripening of the cheese and there for the
flavor of the cheddar cheese is depending on the time of the maturation
 Cheddars must have a maximum moisture content of 39 percent and a minimum
milk fat content of 50 percent by weight of solids (FDA, 2021)
 Most water-insoluble components are retained in the curd
 Cheddars may have protein (casein), fat, calcium, phosphorous and vitamin A
concentrated 8 to 10 times more than that of fluid milk
 Most water-soluble components, including whey proteins, water-soluble salts and
lactose, are dispersed in whey, which is drained off
 Salt plays an important role in the quality of Cheddar cheese, which include:
controlling the growth of lactic acid bacteria and undesirable bacteria such as
coliforms, staphylococci and clostridia, controlling the final pH of Cheddar cheese
as a result of starter culture activity retardation, and controlling overall flavor and
texture of the cheese
 The main method of salting Cheddar cheese curd is directly mixing dry salt
crystals into milled or stirred curd pieces after whey removal

17
Composition of Cheddar Cheese
The moisture content cannot be exceed 39 % and the milk fat content may not be less
than 31 %.
Typical Composition of Cheddar Cheese
Components Percentage (%)

Moisture 37

Protein 25

Fat 33

Carbohydrate 1

Ash 4

Processing line of Cheddar Cheese

Milk Treated Cooling Culture Pre-ripening

at 65-68C 30-31C Addition 15-45min

Renneting 31- Scalding

32C Stirring For
Cutting 39℃-40℃
5 min in 30 min
Time 35-45min

Gradual Increase Stirring and Full

of Temp within Half Whey Whey Drainage
30min Drainage
pH 6.65-6.3

Piles Cutting Milling at pH Salting at Hooping

& Cheddaring 5.6-5.3 1.5% Pressing

Opening of Vacuum Cold Storage

Hoops Packing 3℃-4℃

18
Manufacturing Steps of Cheddar Cheese
Treating the Milk (Pasteurization)
 The vast majority of the cheddar cheese
produced from pasteurized milk held at 65-
68℃ for less than 30 min. pasteurization
destroy the pathogenic bacteria and also
reduce the population of the microbes
 Cheddar cheese also made from the raw
milk
 Some believe that the cheese produced from low heat load has better flavor than
pasteurized milk. Because more of the enzymes and microbes that contribute
flavor may survive
Starter Culture
One the cheese milk is prepared starter culture is
added to generate lactic acid from lactose
Add Rennet
 The activity of the added rennet serves to
produce the casein coagulum
 Rennet was added at a temp. of 31-31C and
at this stage pH was 6.65-6.75
Setting the Curd
 Once the rennet is added the culture must be allowed to set and form the curd
 It takes anywhere 30-40 min to set the curd
Cutting the Curd
 The curds are cut into cubes using stainless
steel knives
 It is important to cutting the curd first
horizontally then vertically
Cooking the Curd (Scalding)
 The curds are stirred and warm to release the
whey then whey drain off from the cheese
 This process is called scalding that held at a
temp. of 39-40C for 30 min

19
Cheddaring
 Cheddaring is the unique process to making
the cheddar cheese
 In this steps curds are allowed to mat together
to form the large block of the cheese mass
 These are worked and expel to further whey
and also produce the characteristics fibrous texture of cheddar cheese
Milling and Salting
 After cheddaring, the curd is milled into smaller pieces and salt are added at 1.5 %
by weight for flavor and preservation
 Salts are also help to remove some of the whey
Pressing and Packaging
 The curds are placed into molds that will be
used to press the curds and forms the blocks of
the cheddar
 After this cheddar will be aged
Aging and Storage
Aging time depends on the type of cheddar. Basically cheddar cheese is stored for 3
months and store at a temp of 2-3C
Application based and End Use
Cheddar cheese is a multifunctional ingredient suitable for use in virtually all types of
products including entrées, side dishes, bakery products, soups, sauces, snack foods,
meat products, vegetable products, etc.
Bakery Products
Cheddar cheese provides flavor and visual appeal
to baked products. It may be melted on the surface
of baked products or shredded and added to dough
prior to baking.

20
Fondue’s and Sauces
Spray dried cheddar cheese powder adds flavor and consistency to hot fondue’s and
sauces.
Frozen Foods
Shredded cheddar cheese provides added value to frozen appetizers, garlic bread, and
quiche and as part of a cheese blend on pizza. The cheddar supplements the flavor,
texture and appearance of these products.
Application
 Processed cheese
 Bakery products: melted, grated, shredded, it may be added in the dough before
cooking
 Soups
 Melted / Sauces: Cheddar, as powder dried by atomization, will give consistency
and taste
 Ready-cooked dishes (garlic bread, pizza)
Mozzarella Cheese
 Fresh mozzarella cheese is generally white but may very seasonally to slightly
yellow depending on the animal diet
 Mozzarella cheese belongs to a class of ‘Pasta filata’ family which involves the
principle of skillful stretching of the curd in hot water to obtain smooth texture in
cheese
 The cheese is soft, white, un-ripened, that may be consumed shortly after
manufacture
 Due to its high moisture content it is traditionally served the day after it is made
but can be kept in brine for up to a week or longer when sold in vacuum sealed
packages
 The specific melting and stretching characteristics of
Mozzarella cheese is highly appreciated in the
manufacture of Pizza in which it is a key ingredient
 Low moisture mozzarella can be kept refrigerated
for up to a month
 Mozzarella is America´s favorite cheese accounting for nearly a third of the
consumption, since it is one of the main ingredients of pizza

21
 The physical and sensory quality of Mozzarella cheeses prepared from cow and
buffalo milk were found to be similar. Buffalo milk Mozzarella (BMM) cheeses
were associated with higher fat, protein, ash (including calcium) and total solids as
compared to cow milk cheese
 Use of buffalo milk led to Mozzarella cheese possessing whiter colour, more
piquant and aromatic flavor as compared to that prepared from cow’s milk
 The cow milk Mozzarella (CMM) cheese tended to be softer, more flexible and
contained slightly higher moisture, fat and salt content unlike BMM cheese which
were associated with higher protein content
 Country of Origin: Italy
 Source of milk: Buffalo
 Pasteurized: Sometimes
 Texture: Semi-soft
 Fat content: 22 %
Composition of Mozzarella Cheese
Components Percentage (%)

Moisture 52

Protein 20.5

Fat 22.5

Carbohydrate 2

Ash 3

22
Processing line of Mozzarella Cheese

Milk Treated Cooling Culture Pre-ripening

at 65-68C 30-31C Addition 15-45min

Renneting 31-
32C Scalding
Stirring for
Cutting 39℃-
Time 35- 5 min 40℃
45min
30 min

Gradual
Increase of All Whey Block Cutting Milling at pH
Temp within Drainage & Cheddaring 6.2-6.1
30min

Stretching and Cooling at ice Packing &

Molding in Covered
Salting at Storage Temp.
Hot Water at Water at
1.5% 4℃ for Time
Temp. 80- Temp. 2℃- 24 hour
85℃ 3℃

Freezing at
Till Marketing
18-35℃

Manufacturing steps of Mozzarella Cheese

Treating the Milk (Pasteurization)
 The vast majority of the mozzarella cheese
produced from pasteurized milk held at 65-
68℃ for less than 30 min. pasteurization
destroy the pathogenic bacteria and also
reduce the population of the microbes
 Mozzarella cheese also made from the raw milk
 Some believe that the cheese produced from low heat load has better flavor than
pasteurized milk. Because more of the enzymes and microbes that contribute
flavor may survive

23
Starter Culture
One the cheese milk is prepared starter culture is
added to generate lactic acid from lactose
Add Rennet
 The activity of the added rennet serves to
produce the casein coagulum
 Rennet was added at a temp. of 31-31℃ and at
this stage pH was 6.65-6.75
Setting the Curd
 Once the rennet is added the culture must be
allowed to set and form the curd
 It takes anywhere 30-40 min to set the curd
Cutting the Curd
 The curds are cut into cubes using stainless
steel knives
 It is important to cutting the curd first
horizontally then vertically
Cooking the Curd (Scalding)
 The curds are stirred and warm to release the
whey then whey drain off from the cheese
 This process is called scalding that held at a
temp. of 39-40C for 30 min
Cheddaring
 Cheddaring is the unique process to making
the mozzarella cheese. In this steps curds are
allowed to mat together to form the large block
of the cheese mass
 These are worked and expel to further whey
and also produce the characteristics fibrous texture of Mozzarella cheese

24
Milling and Washing in Hot Water
The blocks are milled and the curds are then heated in hot water. Milling was done at
pH 5.2-5.1.
Stretching and Moulding
 Stretching and molding of cheese in hot water
at temp. 80-85C
 Cheese stretched to orient the protein and fat
components of cheese and generate the
characteristics of mozzarella texture
 The heat involved in this treatment also denatures the rennet enzymes and prevent
the proteolysis in the curd
 The curd is then moulded into a proper form and transferred into a brine solution
for several hours
 Brining steps allow salt to migrate into the cheese for both flavor and preservative
effect
 Brining also stop the activity of the starter culture
Cooling in Ice Water
After the stretching machine mozzarella is placed
in ice covered water where it is cooled at temp of
2-3C.
Packaging and Storage
 Then cheese is packed and stored at 4C
 After 24 hours freeze at -18C to -35C till marketing
Application based and end uses of Mozzarella Cheese
Mozzarella Cheese is versatile cheese that can be used in various ways. It is
commonly used in cooking and adds a creamy and melty texture to dishes. Mozzarella
cheese and tomatoes make a particularly excellent pairing. Of course, the best known
use of mozzarella cheese is in Italian dishes such as lasagna and melted on top of
pizza. Mozzarella is used for most types of pizza and several pasta dishes or served
with sliced tomatoes. Its mild and slightly salty flavour makes it a popular choice for
many recipes.

25
Pizza
Mozzarella is considered the best cheese for pizza for a few reasons: its delicate,
milky flavor, its smooth, elastic texture, and its fabulous meltability. The texture
comes primarily from the fact that it is a pasta filata-type cheese (“spun paste” in
Italian). Mozzarella cheese provides mild flavor, visual appeal and characteristic
textures when melted on the surface of a pizza. Mozzarella melts smoothly and
browns nicely when baked.
Cream Sauce
Puree fresh buffalo mozzarella with some of its liquid and olive oil to make a spoon
able sauce to top vegetables.
Baked Goods
Mozzarella cheese can be melted on the surface of baked goods to provide visual and
textural appeal as for pizza.
Italian Dishes
Mozzarella cheese baked into dishes will provide flavor, as well as textural benefits
including the stretch and stringiness of the melted cheese.

26
 4. TEST PERFORMED AT RECEPTION LAB
Milk Reception System
Wheel Washing Panel
When vehicle from the collection centre brought milk from the collection centre’s it
come at the vehicle washing stand. The wheels of vehicle are being washed before
the sampling to insure the hygiene.
Sampling Procedure
 The vehicle comes at the sampling point
 Sampler first of all insures the seals of vehicle
 Then sampler measures the temperature of milk and then takes the sample
 Khadam Milk Foods do not compromise on the quality of raw milk. To insure the
quality these tests are performed
Organoleptic Testing Taste
Check taste of milk. It should not give odd taste
Smell
Take in the aroma of milk. It should be of milky odor
Appearance
Milk should be of uniform color and texture
Visible Black Particle
No visible black particles present in the milk. It should be free from dust
Milk Reception Laboratory Test Milk
Analysis Test
 Organoleptic Test
 LR Test
 Reichert Meissl Value (RM) of Desi
Ghee
 COB (Clot on boiling)
 Determination of fat in milk
 APT (Alcohol Precipitate Test)
 % Acidity Determination of Liquid Milk
 Determination of S.N.F and Total Solids of Milk

27
 Organoleptic Test
Organoleptic test rapidly detects poor quality milk at the milk collection point. Milk
grader is required to have good sense of sight, smell and taste.
Materials
There is no need of any equipment and testing reagent.
Procedure
 Open can of the milk
 Smell the milk immediately
 Observe the appearance of the milk
 In case the grader is unable to make a clear decision for the quality of milk, then
taste the milk
 Look at the lid and the container to check its cleanliness
Precaution
Do not swallow but spit the milk sample into the specified container. Milk supplier
may add some desensitizing chemical for grader.
Lactose Reading Reagents
and Apparatus
 Sample of milk
 Thermometer
 Volumetric flask
 Lactometer
Procedure
 Take sample 0f milk
 Raised their temperature upto 40℃ by heat
 Then maintain at 20℃
 Check temperature of milk with thermometer
 Add milk sample in volumetric flask and dip lactometer in it
 Note the readings
Results
 If LR value of milk is 26 it means milk quality is good
 No lower value of LR is acceptable

28
Determination of Reichert Meissl Value (RM) of Desi Ghee
Reichert Meissl (RM) value is the important indices of quality of milk fat. Reichert
meissl is also used to check the adulteration of fat in milk.
Definition of Reichert Meissl Value (RM)
RM value is the number of milliliters of 0.1N aqueous alkali solution required
neutralizing the steam volatile and water soluble fatty acids distilled from 5 g of ghee
/fat under specified conditions.
Principle
In this method, milk fat is saponified
using glycerol- alkali solution, diluted
with water and acidified by sulphuric
acid to liberate free fatty acids.
Apparatus
 Round bottom flask
 Funnel
 Filter paper
 Volumetric cylinder
 Distillation unit
 Bunsen burner
 Beaker
Chemicals and Reagents
 Sample of desi ghee
 25ml Glycerol
 2ml Sodium hydroxide(base)
 95ml of distilled water
 50ml Sulphuric acid
 Phenolphthalein indicator
 Pinch of pumic stone
Procedure
 Take 5g sample of desi ghee in round bottom flask
 Add 25 ml of glycerine in sample
 Then add 2 ml of NaOH

29
 Heat the flask over a naked flame with continuous mixing and the liquid becomes
perfectly clear liquid
 Then add 95 ml of distilled water
 Add 50 ml of the dilute sulphuric acid and pinch of pumic stone
 Connect the flask at once with a distillation apparatus
 Heat the flask without boiling its contents, until the insoluble acids are completely
melted
 When the distillate reaches the 100ml mark, remove the flame and replace the
110 ml flask with a cylinder of about 25ml capacities to catch draining
 Filter through a dry 9cm open texture filter paper (What man No. 4) which fits
snugly into the funnel. Reject the first running and collect 100 ml in a dry
volumetric flask; cork the flask and retain the filtrate for titration
 Pour 100 ml of the filtrate containing the soluble volatile acids into a titration
flask, add 0.1 ml of phenolphthalein indicator and titrate with 0.1N sodium
hydroxide solution until the liquid becomes pink
Results
Reichert Meissl Value (RM) of Desi Ghee is 26.
Clots on Boiling Test
 Clot on boiling (C.O.B) is quick and simple.
It is one of the old tests for too acid milk
(pH<5.8) or abnormal milk (e.g. mastitis
milk)
 If a milk sample fails in the test, the milk
might be containing acids or acid producing
bacteria or abnormally high level of
proteins such as in colostrum
 Such milk turned into curd or clot on heat treatment during milk processing so
such milk must be rejected
Materials
 Test tube one
 Test tube holder
 Milk sample
 Bunsen burner or spirit lamp

30
  Matches
Procedure
 Take 5 ml milk sample in a test tube
 Hold the tube with test tube holder
 Boil the milk sample in the test tube on the burner for 5 minutes
Result
Clotting or coagulation of the sample in the tube indicates the failure of the sample to
C.O.B test.
Comments
This test may fail to detect the quality if:
 Freshly drawn milk is contaminated with bacteria
 Acidity of the sample is below 0.20-0.26% lactic acid
 Milk is contaminated non-acid producing bacteria
Determination of Fat in Milk
Objective
 The price of milk fixed on its fat content
 To determine the fat level in milk by Gerber method
Precaution
 Carryout through mixing of milk before testing
 Amyl alcohol must be pure
 Sulphuric acid is to be added gently by the sides of the butyrometer without
wetting the neck of the butyrometer. Avoid direct pouring of milk on acid
 The three fluids viz. Sulphuric acid, milk and amyl alcohol should be added
gently, so that they form three distinct layers
 Rubber stopper should be dry, clean and without crack
 Before centrifuging the butyrometer, see that there is no curdy white material left
un-dissolved
 The centrifugal machine must be properly
balanced
 Always carry out the test in duplicate
 Butyrometer should be free from Na2Co3 (soda
ash) if cleaned by Na2CO3 otherwise it lowers
the specific gravity and strength of Sulphuric
acid

31
 Use butyrometer stand for shaking of butyrometer contents to dissolve the SNF
content of milk
Material Required
 Milk
 Sulphuric acid (sp.gr.1.82)
 Amyl alcohol (sp.gr.0.82-0.83)
Apparatus
 Milk sample bottle
 10 ml automatic tilt measure for H2SO4
 1 ml automatic tilt measure for amyl alcohol
 10.75 ml capacity milk pipette
 Dairy floating thermometer
 Hot water bath
 Gerber’s centrifuge machine (1100 rpm)
 Gerber’s butyrometer plain neck with graduations from 0-10%
 Butyrometer stand
 Rubber stopper
 Guiding pin or key
Procedure
 Put the clean and dry butyrometer in a butyrometer
stand with open mouth upwards
 Run 10 ml of sulphuric acid with the tilt measure in
the butyrometer
 Pipette out 10.75 ml of milk sample gently by the
side of butyrometer, whose temperature is about
60-70ºF
 Pour 1 ml. of amyl alcohol with tilt measure
 Stopper the butyrometer with the help of lock stopper using regulating pin/guiding
pin
 The tube is well (mixed) shaken till mahogany red color is obtained.
 Keep the butyrometer in hot water bath till it attains 60-70ºF and the butyrometer
are placed in the centrifuged machine that is revolved at 1100 rpm for 4 minutes
 Take out the butyrometer in an upright position with the stopper end down wards.

32
  Keep the butyrometer in hot water bath a 149ºF (600ºC) for some time
 Adjust the fat column which will appear clear and yellowish within the graduation
with the help of key
 Note the reading. Reading should be taken from bottom of the fat column to lower
border of meniscus on the scale
Alcohol Precipitate Test (APT)
Principle
 Protein of milk and alcohol compete for water available in milk
 The higher the concentration of alcohol used; greater will be it’s power to attract
water
 Consequently less water will be available to keep the casein in suspension
Reagent
Alcohol
Apparatus
 Pipette (10 ml)
 Test tubes
 Glass petri dish
Procedure
 Thoroughly mix the milk to get representative sample
 Take 2 ml milk sample with the help of pipette in a clean test tube
 Add 2 ml alcohol solution of required strength and mix without shaking
Observation
Presence of precipitates will be considered as APT +ve.
Acidity Determination of Liquid Milk Principal
 The acidity of fresh milk (natural acidity) is due to phosphates, casein and whey
proteins, citrates and carbon dioxide
 The natural acidity of milk is 0.12-0.15 %. Figures higher than this signifies
developed acidity due to the action of bacteria on milk sugar
Reagent
 % phenolphthalein indicator
 Distilled water
 0.1 % N NaOH solution

33
Apparatus
 Weighing balance
 Burette
 Pipette 10 ml
 Glass beaker
 pH meter with electrode
 Buffer solution
Procedure
 Weigh 9 ml sample in a 100 ml beaker
 Add 0.5 ml (3-4 drops) of phenolphthalein indicator and swirl to mix
 Fill burette with 0.1 N NaOH up to 0 ml on top and allow it to drain until all air
bubbles have been removed
 Refill the burette and drain until meniscus is at 0 ml mark
 Allow NaOH to drip into the beaker with continuous stirring to a permanent pink
color the phenolphthalein end point is at pH 8.3
 Read level of NaOH in burette and read number of millimeters of NaOH delivered
Calculation
 Acidity is expressed as % lactic acid
 1 ml of 0.1 N NaOH= 0.009 g of lactic acid
 % acidity = ml of 0.1 N NaOH used × 0.009 × 100/ weigh of the sample
 % acidity= ml of 0.1 N NaOH used × 0.1
 No of ml. of 0.1 N NaOH solutions

x 0.009 x 100
Required for Neutralization
% Lactic acid = Weight of Sample

(Weight of sample = Volume of milk x specific gravity)

Determination of S.N.F and Total Solids of Milk
Total Soluble Solids is a measurement of the total concentration of substances that are
dissolved in a liquid. In case of milk, TSS includes various components such as
sugars, salts and dissolved substances. In the context of milk, TSS is used to measure
the overall concentration of solids including both fat and non-fat components.
Objectives
 To estimate the level of Total solid content of milk
 To decide the quality of milk on the basis of total solids and SNF

34
Relevant Information
Total solids content is the entire residue left after complete evaporation of water from
milk. This includes fat protein, lactose and mineral matter. These solid constituents
exist in milk in a mechanical mixture.
Total Solids can be determined by
 Gravimetric method
 By use of formula
 By Richmond’s scale
Reagents
Milk
Apparatus
 Specific gravity bottle
 Balance
 Porcelain dish
 Hot air oven
 Tongs
 Hot water bath
 Desiccators
 Glass jar
 Lactometer
 Dairy floating thermometer
 Petri plate/dish
Procedure
Gravimetric Method
 This is an accurate method but not practicable and hence is not used
 Take flat bottomed 50 cm diameter porcelain crucible
 Clean and dry in hot air oven for 1 ½ hour
 Not the weight of crucible
 Add 5 ml of milk sample and weight it
 Put the crucible in hot air oven adjusted at 100 0 C for 3 to 4 hours
 Remove the crucible from oven and cool in desiccators’ and weight
 Again put the crucible for ½ hour in oven
 Remove the crucible from oven and cooled in desiccators’ and weigh

35
 This process should be continued/repeated till getting the constant weight or
difference in last two weights should not exceed 0.01 gm. The total solids are
determined by formula:
Total solids % =Weight of Residue
× 100
Total Weight

By Use of Formula
 Determine the fat percentage of milk sample by Gerber’s method
 Take out the lactometer reading and temperature of milk and calculate
 Corrected lactometer
 Place the figures of fat and lactose Reading(LR) in the following formula for
calculating total solids and solids not fat

Lactose Reading(LR)
Richmond’s Formula
+
4
Total Solids % = 1.21ºF + 0.14

Lactose Reading(LR)
SNF % = 4 + 21ºF + 0.14
By Richmond’s Scale
 To have immediate results the total solids content is determined by Richmond’s
scale
 The mechanical device made in the form of a ruler with a sliding centre slip
 The total solids can be determined if lactometer reading, temperature of milk and
fat content is known
 The observed lactometer reading is placed opposite the little arrow at 60 0 F on
the temperature scale
 The corrected lactometer is observed opposite the line indicating observed
temperature of milk
 This would give the corrected lactometer reading
 Next, the arrow on the sliding portion is placed against the fat content of the given
milk and bottom part of scale would give the percentage of total solids opposite to
the lactose reading(LR) on small scale

36
pH Test
Purpose
pH test is performed to judge the keeping quality of milk or to estimate the intensity
of acidity/alkalinity of milk. However, milk generally has a slightly acidic pH,
ranging from around 6.4-6.8. Fresh cow's milk has a pH around 6.6-6.8. Values
greater than 6.8 indicate that the milk has coagulated and a value below 6.5 indicates
the presence of colostrum or bacterial contamination. When the pH is less than 6.5,
this provides an indication that significantly acidic development has occurred, due to
the increased bacterial activity. The pH can vary depending on factors such as
freshness of milk and the presence of any additives or processing methods.
Procedure
 Take milk sample
 Dip the end of pH meter in milk
 Wait for few seconds until reading is stable
 Note the reading Result Fresh milk has a pH 6.6-6.8
Alcohol Test
It also known as Platform test. For this test 68% ethanol is used.
Purpose
To determine acidity of milk alcohol test is occurred.
Apparatus
 Test tube
 Pipette Reagents
Procedure
 For platform test at first 2ml of 68% ethanol is taken into a test tube through a 5ml
pipette
 Then 1ml milk is added into the test tube
 Shake the sample for some time. And look for coagulation
Result
Coagulation of milk and stability of milk with the test tube’s body is alcohol positive.
No coagulation means alcohol negative

37
5. ADULTERATION TEST
There are many methods known for detection of adulteration in milk but the methods
discussed below are simple but rapid and sensitive methods to detect adulteration.
Soda Test
In milk neutralizers like hydrated lime, sodium hydroxide, sodium carbonate or
sodium bicarbonate are added which are generally prohibited.
Procedure
 Take 5 ml of milk in a test tube
 Add 5 ml alcohol followed by 4-5 drops of Rosalie acid
Result
 If the color of milk changes to pinkish red, then it is inferred that the milk is
adulterated with sodium carbonate / sodium bicarbonate and hence unfit for
human consumption
 This test will be effective only if the neutralizers are present in milk. If the added
neutralizers are nullified by the developed acidity, then this test will be negative.
In that case, the alkaline condition of the milk for the presence of soda ash has to
be estimated
Test for Detection of Hydrogen Peroxide
 Take 5 ml milk in a test tube
 Now add 5 drops of paraphenylene diamine and shake it well
Result
Change of the colour of milk to blue confirms that the milk is added with hydrogen
peroxide.
Test for Detection of Formalin
Formalin (40%) is poisonous though it can preserve milk for a long time.
Procedure
 Take 10 ml of milk in test tube
 Now 5 ml of conc. sulphuric acid is added on the sides of the test tube without
shaking
Result
If a violet or blue ring appears at the intersection of the two layers, then it shows the
presence of formalin.

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 Test for Detection of Sugar in Milk
Generally sugar is mixed in the milk to increase the solids not fat content of milk i.e.
to increase the lactometer reading of milk, which was already diluted with water.
Procedure
 Take 10 ml of milk in a test tube
 Add 5 ml of hydrochloric acid along with 0.1 g of resorcinol
 Then shake the test tube well and place the test tube in a boiling water bath for 5
min
Result
Appearance of red colour indicates the presence of added sugar in milk.
Test for Detection of Starch
Addition of starch also increases the SNF content of milk. Apart from the starch,
wheat flour, arrowroot, rice flour are also added.
Procedure
 Take 3 ml milk in a test tube and boil it thoroughly
 Then milk is cooled to room temperature and added with 2 to 3 drops of 1%
iodine solution
Result
Change of colour to blue indicates that the milk is adulterated with starch.
Test for Detection of Urea
Urea is generally added in the preparation of synthetic milk to raise the SNF value.
Procedure
 Take 5 ml of milk in test tube
 Now mixed well with 5 ml paradimethyl amino benzaldehyde (16%)
Result
If the solution turns yellow in colour, then the given sample of milk is added with
urea.
Detergent Test Principal
Milker’s remove fat and added water in the skimmed milk. The result the milk watery
and lack of so that milker’s add detergent to improve the milky foam formation.
Procedure
 Take 10 ml of milk in a test tube and dilute it with equal quantity of hot water

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  Then add 1 – 2 drops of phenolphthalein indicator
Observation
Development of pink color indicates that the milk is adulterated with soap.
Sodium Chloride (NaCl) Test
Principal
Addition of salt in milk is mainly resorted to with the aim of increasing the corrected
lactometer reading. Addition of table salt in milk is toxic for consumer suffering from
blood pressure.
Procedure
 5 ml of silver nitrate (0.8%) is taken in a test tube
 Add 2 to 3 drops of 1% potassium dichromate and 1 ml of milk and thoroughly
mixed
Observation
If the contents of the test tube turn yellow in color, then milk contains salt in it. If it is
red colored, then the milk is free from salt
Detection of Borax and Boric Acid in Milk
Procedure
 Five ml of milk is taken in a test tube to which 1 ml of concentrated hydrochloric
acid is added and mixed well
 Tip of a turmeric paper is dipped into the acidified milk and it is dried in a watch
glass at 100°C or over a small flame
Result
 If the turmeric paper turns red, it indicates the presence of borax or boric acid
 Confirmation can be made by adding a drop of ammonia solution on the turmeric
paper and if the red colour changes to green, it shows the presence of boric acid
Detection of Water in Milk
 Though the adulteration of milk with water can be checked by lactometer reading,
other adulterations too affect the lactometer reading
 Hence freezing point depression, recognized by AOAC, is usually adopted
 Normal freezing point of milk is taken as –0.55°C
 A tolerance level of 3% is given which is equivalent to specifying a minimum
freezing point depression for authentic milk of –0.55°C

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Detection of Skim Milk Powder in Milk
 If the addition of nitric acid drop by drop in to the test milk sample results in the
development of orange color, it indicates the milk is adulterated with skim milk
powder
 Samples without skim milk powder shows yellow color
Detection of Vegetable Fat in Milk
 The characteristic feature of milk is its fatty acid composition, which mainly
consists of short chain fatty acids such as butyric, caproic, and caprylic acid
 The vegetable fats consist mainly of long chain fatty acids and hence adulteration
of vegetable fat in milk can be easily found out by analyzing the fatty acid profile
by gas chromatography
Detection of Buffalo Milk in Cow Milk
 The presence of buffalo milk in cow milk is tested by Hansa test
 It is based on immunological assay
 One ml of milk is diluted with 4 ml of water and then it is treated with 1 ml of
antiserum
 The characteristic precipitation reaction indicates the presence of buffalo milk in
the sample taken. (The antiserum is developed by injecting buffalo milk proteins
into rabbits)
Detection of Benzoic and Salicylic Acid in Milk
 Five ml of milk is taken in a test tube and acidified with concentrated sulphuric
acid. 0.5% ferric chloride solution is added drop by drop and mixed well
 Development of buff color indicates presence of benzoic acid and violet colour
indicates salicylic acid
Test for Detection of Salt
Addition of salt in milk is mainly resorted to with the aim of increasing the corrected
lactometer reading.
Procedure
 Five ml of silver nitrate (0.8%) is taken in a test tube
 Now add 2 to 3 drops of 1% potassium dichromate
 Add 1 ml of milk and thoroughly mixed

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 Result
 If the contents of the test tube turn yellow in colour, then milk contains salt in it
 If it is chocolate colored, then the milk is free from salt
Test for Detection of Ammonium Sulphate
The presence of sulphate in milk increases the lactometer reading.
Procedure
 5 ml of hot milk is taken in a test tube and added with a suitable acid for e.g. citric
acid and the whey thus separated is filtered
 Collect the whey in another test tube and add 0.5 ml of 5% barium chloride
Result
Appearance of precipitate indicates the presence of ammonium sulphate in milk.
Test for Detection of Glucose
Usually poor quality glucose is added to milk to increase the lactometer reading.
There are two tests available to detect the adulteration of milk with glucose.
How to proceed? Phosphomolybdic
or Barford Test
 Take 3 ml of milk in a test tube
 Add 3 ml bar ford’s reagent and mix it thoroughly
 Then keep it in a boiling water bath for 3 min
 Then cool it for 2 min by immersing in tap water with-out disturbance
 Now add 1 ml of phosphomolybdic acid and shake
Result
If blue colour is visible, then glucose is present in the milk sample
Diacetic Test
 Take a strip of diacetic strip and dip it in the milk for 30 sec to 1 min
 If the strip changes colour, then it shows that the sample of milk contains glucose
 If there is no change in the colour of the strip, then glucose is absent
Result
In this method the presence of glucose in milk can be quantified by comparing the
colour developed with the chart strip

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6. MICROBIAL TEST
Yeasts, moulds and a broad spectrum of bacteria can grow in milk, particularly at
temperatures above 16°C. Microbes can enter milk via the cow, air, feedstuffs and
milk handling equipment. Once microorganisms get into the milk their numbers
increase rapidly. Bacterial types commonly associated with milk are:
 Pseudomonas
 Enterobacteriaccae
 Staphylococcus aureus
 Staphylococcus thermophiles
 Staphylococcus Cremoris
Test for Microbiology
 Salmonella
 Yeast and Mold
 Coliform
 Escherichia Coli
Yeast and Mould Count
 Yeast and Mold constitute large and
diverse group of microscopic food
borne fungi totally several hundred
different species
 These organisms are so successfully in
attacking food and cosmetics is their
versatility having very broad temp
Reagents
 Potato dextrose sugar
 Distilled water
 Ringer tablets
 pH Buffer
Media Preparation
 Dissolve 39g of media into 1 lit. distilled water
 Sterilize at 121℃(15 psi) for 15 min
 Pour 10ml into petri dish

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Inoculation
 Take 1ml sample into petri dish
 Add 12-15ml agar
 Immediately mix and solidify
Incubation
 Incubate at 25℃ for 72 hours
Result Interpretation
 Count while colonies as yeast and large colored fuzzy colonies as mold
Total Coliform Count (TCC)
Reagent and Culture Media
 Mac Conkey agar
 Distilled Water
 PH Buffer
 Ringer Tablets
Media Preparation
 Dissolve 50g media into petri dish and add 1 lit. distilled water
 Sterilize at 121℃ (15 psi) for 15 min
 Pour 10ml into petri plates
Inoculation
 Take 1ml into petri dish
 Add 12-15ml agar
 Immediately mix and solidify
Incubation
 Incubate at 35℃ for 48 hours
Result Interpretation
 Count pink colonies as coliform
 Count red colonies as E.coli
Salmonella Count
Reagents
 XLD agar
 Distilled water
 PH buffer
 Ringer Tablets

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Media Preparation
 Dissolve 22.5g media in 1 lit. distilled water
 Heat with frequent agitation just until media boils
 Do not autoclave
 Pour 10ml into petri dish
Inoculation
 Take 1ml sample into petri dish
 Add 12-15ml agar
Incubation
 Incubate at 35℃ for 48 hours
Result Interpretation
 Count pink, yellow or black colonies as salmonella
Total Listeria Count (TLC)
Reagents and Media Culture
 Muller Hinton agar
 Distilled Water
 PH Buffer
 Ringer Tablets
Media Preparation
 Dissolve 38.0g media into 1 lit. distilled water
 Sterilize at 121℃ (15 psi) for 15 min
 Pour 10ml into petri plates
Incoculation
 Take 1ml sample with petri dish
 Add 12-15ml agar
 Immediately mix and solidify
Incubation
 Incubate at 35℃ for 48 hours.
Result Interpretation
 Count blue and blue-grey colonies as listeria

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Determination of E.coli
Intoduction
Escherichia coli are a bacterium that commonly
inhibits the lower intestine of warm blooded
animals. E.coli is able to service for short periods
of time outside of its host and therefore it is an
ideal indicator of fecal contamination of water.
Commonly acquired by eating undercooked meat or unpasteurized milk, but it can
travel through water and cause infection to swimmers or contaminate vegetables crops
via irrigation water.
Chemical
 Methylene blue agar
 Peptone water
Agar Preparation
 First take 200ml distilled water
 And weight 5.6g nutrient agar
 Mix 5.6g agar in 200ml distilled water in conical flask
 Heat it until it boils and close it with cotton stopper and sterilize it
Sample Preparation
 Take 400ml water and 0.4 g peptone salt
 And after that take 90ml in 2 bottles and tightly close it with cap
 Take pipette and fill it with 9ml mixture of distilled water and peptone salt in each
test tube and place all in autoclave
 Temperature goes to 121oC and autoclave it starting time is 30 min after 30 min
automatic stop and again give it time for 15 min and open it
 And placed it in laminar air flow for 15-20 min. Add sample in bottles mix it
gently and give rest for some time until the sample particle settle down then take
sample and add it in Petri dish NO 1
 And take sample from bottle and add in test tube having peptone water and mix it
and take peptone water. With added sample and add it in Petri dish
 Add agar in each Petri dish when temperature become down between 45-50oC
 Give rest and after that placed it in hot incubator for 24 hour at temperature 37-
42oC

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7. PLANT SANITATION
Plant sanitation includes the following two major steps; cleaning in place (CIP) and
cleaning out of place (COP).
Cleaning in Place (CIP)
CIP is a time efficient process of cleaning vessels that cannot be cleaned manually
from outside. This process involves the removal of soil from product contact surfaces
(i.e. pipeline of milk processing equipment) in their process position by circulating,
spraying or flowing chemical solutions and water rinses onto and over the surfaces to
be cleaned. Components of the equipment that are not designed to be CIP are
removed from the equipment to be manually cleaned. It is a crucial step for the
documentation of HACCP. In case of milk processing equipment or vessels, CIP
procedure is explained below.
The CIP process can consist of the following elements:
 Supply pump
 Return pump
 Heat exchanger with Black/Plant steam supply
 Chemical tanks(Acid, Alkali tanks)
 Supply Pressure gauge or transmitter
 Supply temperature sensors
 Conductivity meter with sensor
Procedure
 When the vessels are empty and ready to be clean, they are firstly rinsed with
warm water for about 10 min.
 After rinsing with water, 2-2.5% base or alkali solution of sodium hydroxide is
circulated through the pipes at approximately 70-80C temperature for 10 min.
 Then the pipes are again rinsed with warm water.
 Now 1-1.25% acid solution (commonly nitric acid) is circulated through the
vessels or pipes at about 50C temperature for 10 min.
 Now it is again rinsed with warm water until the pH becomes 7
Cleaning Out of Place (COP)
Cleaning out of place is defined as a method of cleaning equipment items by
removing them from their operational area and taking them to a designated cleaning

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station for cleaning. It requires dismantling an apparatus, washing it in a central
washing area using an automated system, and checking it at reassembly.
Manual Cleaning
Manual cleaning is the universal practice among the pharma and biopharma
industries. The design, configuration and construction of equipment or the whole
equipment which necessities the manual cleaning for the piece of equipment. The
efficiency of the manual cleaning accomplished by training the cleaning operators,
ensuring exact method of cleaning in the manual cleaning SOP, validating the method
from different operators and verifying the procedure with interval of time.
The manual cleaning is dependent on,
 Concentration of detergent used
 Temperature of washing liquid
Immersion Cleaning
This is the type of cleaning in which the parts to be cleaned are placed in the cleaning
solutions to come in contact with the entire surface of the parts.
The important aspects during design of immersion washer should be
 To minimize cycle time
 Lower chemical usage
 Reduce water and utility costs
Performance for immersion cleaning can be improved by moving the parts within the
liquid or with agitation of the liquid, mechanically or with the addition of ultrasonic
energy.

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8. LEARNING OUTCOMES
Working as an intern at Khadam Milk Foods for 8 weeks enables me to know the
working procedure at different department like production department and quality
department. I also learned about behaviour issues which are important for every
organization. I not only got exposure to the professional world but also successful to
change attitude and behaviour in the daily life spending. In this short time internship
programme provided me an opportunity to work in different settings and exposed me
to interaction with different sets of people. The working environment of Industry was
highly motivating and inspiring. I worked in different departments of industry and in
every department I worked with a new set of people. I worked in quality department
like maintaining the reports according to sample specifications. After successful
completion of the internship, following learning outcomes were achieved: I learned
about working environment and importance of time management and need of
communication skills. I learned to make new connection like maintain friendly
relation with seniors and juniors. I learned about working responsibility, work
pressure and how to handle the work pressure. I learned to keep professional and
personal life separate and appear cheerful in front of everyone during working. I
learned to face and handle problem effectively and efficiently. The caring attitude
towards each other is essential for teamwork. I quickly realized my low level skills
during my internship period. I learned how to talk about my interest, knowledge and
skills with others and how to ask questions. Demonstrate professional behaviors
expected within the food service industry. Provide customer service to clients within
the food service industry. After internship students will be able to work at industry
level and easily handle their working problems. Internship is a great way to apply
your learning skills into the workforce. Having an internship gives you more work
experience.

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 CONCLUSION
This internship was my first experience in the market. Main products of this industry
are "Khadam's Desi Ghee", "Khadam's Butter", and “Mozzarella Cheese” and Fresh
Cream. Practical knowledge is far more important and a better way to learn what we
study in the classrooms, hence, internship provided me the opportunity to implement
my course book knowledge for the betterment of the industry. The atmosphere at my
work place was really pleasing and good. Additionally, I felt like I was able to
contribute in this work for example I did testing on different samples for my
supervisor on daily basis and submit the results at the end of the day. It was very
helpful for my further studies. I worked in quality department and working in quality
control reports according to sample specifications. During my internship period, I
learned about laboratory testing and analysis (Milk Fat, RM, COB, APT, and LR).
Being a part of the quality team I conducted different tests in quality lab.
Conclusively, this internship helped me to learn about food safety, quality for
manufacturing and import and export during packaging.

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