Food processing, composition of milk, microorganism present, Different type of adulteration test (sugar, starch, Salt, urea), biochemical test (organoleptic, clot on boiling, alcohol, lactometer, fat determination, protein determination), different type of pasteurization, processing, spray drying, Standards of PFA, FSSAI, BIS (profile and regulations) & non food application of milk.

1. FOOD PROCESSING
Preservation & Quality Analysis of
Dairy Products
Presented By – AYUSH MISHRA,
BS-16-227
BIOTECHNOLOGY
Guided By – Dr. Monalisha Rath

2. What is Food Processing ?
Food processing is the transformation of agricultural products into
food, or of one form of food into other forms.
Food processing includes many forms of processing foods, from
grinding grain to make raw flour to home cooking to complex
industrial methods used to make convenience foods.

3. Classification
Food Processing is divided into 3 parts
Primary food processing
Secondary food processing
Tertiary food processing

4. Primary food processing
Primary food processing turns agricultural products , such as raw wheat kernels or
livestock, into something that can eventually be eaten
Secondary food processing
Secondary food processing is the everyday process of creating food from ingredients
that are ready to use. Baking bread
Tertiary food processing
Tertiary food processing is the commercial production of what is commonly called
processed food. These are ready-to-eat or heat-and-serve foods, such as TV dinners
and re-heated airline meals.

5. History
Evidence for the existence of these methods can be found in the
writings of the ancient Greek, Chaldean, Egyptian and Roman
civilizations as well as archaeological evidence from Europe,
North and South America and Asia.
In Mesopotamia civilization; Sumerians drank beer, wine & other
beverages along with they dried animal foods like meat, pork,
beefs & etc.
Harappan also were able to grow their own pulses, fruits &
vegetables store those products in underground SILOS after sun
drying.

6. Modern food processing technology
Modern food processing technology developed in the 19th and 20th
centuries was developed in a large part to serve military needs.
In 1809 Nicolas Appert invented a hermetic bottling technique that
would preserve food for French troops which ultimately contributed to
the development of tinning, and subsequently canning by Peter Durand
in 1810.
Pasteurization, discovered by Louis Pasteur in 1864, improved the
quality and safety of preserved foods and introduced the wine,
beer, and milk preservation

7. Dairy Processing
India is the world’s largest producer of milk, and is the leading exporter of
skimmed milk powder.
China and Russia are the world’s largest importers of milk and milk
products. Throughout the world, there are more than six billion consumers
of milk and milk products. Over 750 million live dairy farming households
Dairy processing deals with preservation, quality analysis & derivation of
new product from milk.

8. COMPOSITION OF MILK
MILK FAT - Milk fat is the mixture of 19 fatty acids
PROTEIN - The protein of milk consists of casein, lacto globulin and lacto albumin found in milk
WATER - It provides the medium in which all the milk constituents are dissolved
LACTOSE (MILK SUGAR) - It exists in true solution phase and formed by bacteria yield lactic acid.
MINERALS - These are mostly salts like Mg, p, and N etc.
PHOSPHOLIPIDS - These are 3 types of phospholipids (Lecithin, Cephalin , and Sphingomycin)
PIGMENTS -Carotene is responsible for yellow color acts as antioxidant & as source of vitamin A.
MILK ENZYMES - Anise (Disaster) Lipase, Phosphatase, Protease & Catalase
VITAMINS - Vitamins are present in minute quantity in milk. ( A,D,B,K,E & etc )

9. TYPES OF MICROORGANISMS FOUND IN MILK
Bacteria - These are microscopic, unicellular, occur in the form of spherical, Cylindrical or
spiral shape.
Moulds - Multicellular at maturity and as mycelium is useful in cheese making which is
responsible for defects in butter & other milk products.
Yeast - Unicellular, larger than bacteria, destroyed during pasteurization.
Virus - These are ultra-microscopic forms which can be destroyed by pasteurization on higher
heat treatment.

10. BIOCHEMICAL TESTS OF MILK
The tests are conducted by the receiver at the start of milk reception :
ORGANOLEPTIC TEST - It means normal check of color, flavor and taste
CLOT ON BOILING TEST - This test is carried out for milk to know it’s heat tolerance
which is related to bacteria, acidity and freshness of milk.
ALCOHOL TEST - This test shows heat and salt tolerance of milk. 68% of
ethylalcohol added & shaken. If precipitated test is positive.

11. LACTOMETER READING TEST - This test shows adulteration of water in milk by
dipping lactometer at at 27°C
FAT DETERMINATION TEST - 10 ml of H2SO4 (90%) is taken in butyrometer .
10.75 ml of milk & 1 ml isoamylalcohol added then centrifuge at 1000 - 1100 rpm for
5 min.
SNF= Lactometer reading/4 +Fat% × 0.25 +0.44
Ekomilk ultrasonic milk analyzer is designed for fast and cost effective analyzer of
fat & SNF

12. DETERMINATION OF ADULTRATION -
SUGAR TEST - 1ml of milk sample & 4-5 drops of resorcinol solution added &
boiled for 1 min. Red color shows sugar positive.
SALT TEST - 5 ml of AgNo3 ,5 ml of K2CrO4 3-4 drops & 1 ml of milk added. Yellow
coloration shows salt positive.
UREA TEST- 2ml of milk & 2ml of DMAB added. Intanse yelow color shows Urea
positive.

13. STARCH TEST - 1ml of iodine soln added with 3ml milk. Bluish color shows starch
positive.
NEUTRILIZER TEST - 5ml of milk, 5 ml of ethyl alcohol(95%) & Rosoalic acid (3-4
drops) added. Pink color shows neutralizer positive.
FORMALIN TEST - 10ml of milk, 1 ml of FeCl3 (10%) & 10 ml H2SO4 added. Violet
ring at center shows test positive.
PROTEIN TEST - 10ml of milk, 2ml of phenolphthalein, 0.4 ml of saturated solution
of K2O2 added & titrated against 0.1N NaOH(v). PROTEIN%= V × 1.7

14. PHOSPHATE TEST -
Buffer solution was prepared by dissolving 1.5gm of NaHCO3 & 0.3gm of Na 2 CO3 in
1 liter of distilled water
0.15gm of dissolved P- nitro phenyl phosphate is added in 100ml of above prepared
solution .
5ml of buffer solution is taken in a test tube.
1ml of milk sample is added to it.
It is mixed properly and incubated at 37C in a water bath for 30minutes.
RESULT:--If the solution turns intense yellow in color, it indicates the phosphate test.
If it is colorless or milky, then the test is negative.

15. METHYLENE BLUE REDUCTION TEST
-The sample is mixed by inverting the sample bottle 25 times.
-By using sterile pipette 10ml of the milk sample is taken out into a
sterile test tube
-1 ml of methylene blue solution is added with 1ml sterile pipette
-Tube is plugged with sterilized rubber stopper or cotton plug
-The test tube is placed at 37°C in a thermostatically control water
bath.
-The water level must be above the top of the milk level and should
be covered.
incase water bath is not available keep it in ambient temperature
-With each test tube a controlled incubation maintained.
-After incubation test mixture is compared with positive control
MBRT of Raw Milk

16. GRADE MBRT
Excellent >2.0 Hours
Good 1.0-2.0 Hours
Fair 1.0 Hours
Poor 30 minutes
GRADE MBRT
Excellent > 6.0 Hours
Good 5.0-6.0 Hours
Fair 4.30-5.0 Hours
Poor 4.0 minutes
MBRT of Raw Milk
MBRT of Pasteurized Milk
RAW MILK PASTEURISED MILK

17. PROCESSING OF MILK:
1. From the farm to the processing plant :
Milk is obtained from the cow (or goat, sheep, or water buffalo) under sanitary conditions
and cooled to 45°F (7°C) within 2 hours of milking. Milk is picked up by a handler who takes a
sample and then pumps the milk from farm's into the milk truck. A handler may pick up milk from
more than one farm, so a truck load may contain milk from several farms when it is delivered to the
processing plant.
Before the milk can be unloaded at the processing plant, each load is tested for antibiotic residues, if
the milk shows no evidence of antibiotics, it pumped into plant holding tanks for further processing, if
the milk does not pass antibiotic, testing, the entire truck load milk is discarded and the farm samples
are tested to find the source of the antibiotic residues. Regulatory action is taken against the farm
with the positive antibiotic test. Positive antibiotic tests are rare and account for less than 1 % of the
tank loads of milk delivered to processing plants.

18. Pasteurization:
Pasteurization kills many harmful microorganisms by heating the milk up to a short time up to 80°C
and holds the temperature for 15 seconds and then cooling below 4°C for storage and
transportation
Temperature Time Pasteurization
63°C (145°F ) 30 min LTST
72°C (161°F ) 15 sec HTST
89°C (191°F ) 0.1 sec Ultra Pasteurization
90°C (194°F ) 0.5 sec Ultra Pasteurization
94°C ( 201°F ) 0.1 sec Ultra Pasteurization
96°C (204°F ) 0.5 sec Ultra Pasteurization
100°C (212°F ) 0.01 sec Ultra Pasteurization
138°C (280°F ) 2 sec Ultra High Temp Pasteurization
- To render milk safe for human consumption by destruction of pathogenic microorganisms.
- To improve the keeping quality of milk by destruction of almost all spoilage microorganisms (85-
99%).

19. Processing of WMP & SMP
Whole milk powder & skim milk powder are processed by Spray drying
method.
Inlet air temp 180°C - 250°C
Outlet air temp 80°C - 115°C
Inlet moisture content 75 - 85 %
Outlet moisture content 3 - 3.5 %
Rang of particle size 80μm - 400μm
Spray rate 2290 kg/hr
Air flow rate 31500 kg/hr
Nozzle pressure 700 - 2500 Psi
Operating Condition :

21. Standardization
FSSAI
Food Safety and Standards Authority of India (FSSAI) is an autonomous body
established under the Ministry of Health & Family Welfare, Government of India. The
FSSAI has been established under the Food Safety and Standards Act, 2006 which is
a consolidating statute related to food safety and regulation in India. FSSAI is
responsible for protecting and promoting public health through the regulation and
supervision of food safety.

22. BIS
The Bureau of Indian Standards (BIS) is the national Standards Body of India
working under the aegis of Ministry of Consumer Affairs, Food & Public
Distribution, Government of India. It is established by the Bureau of Indian
Standards Act, 1986 which came into effect on 23 December 1986. The Minister
in charge of the Ministry or Department having administrative control of the BIS is
the ex-officio President of the BIS.
PFA
The laws regulating the quality of food have been in force in the country since
1899.
The Government of India, therefore, enacted a Central Legislation called the
Prevention of Food adulteration Act (PFA) in the year 1954 which came into effect
from 15 June, 1955.

23. NON-FOOD APPLICATION OF MILK :-
Casein and caseinates
Casein is the main protein (24–29 g·L–1) in bovine milk. In fact, casein of milk, involved in highly
hydrated micelles, is based on four major components, αs1-casein (38%), αs2-casein (10%), β-
casein (36%) and κ-casein (13%) and a minor constituent, γ -CN (3%). Each constituent varies in
amino acid composition, molecular weight (19 000–23 900), isoelectric point and hydrophilicity.
Casein as an adhesive
Lime or copper chloride to give water-resistant glues by promoting crosslinking of casein
molecules. dissociating agents such as ammonia or urea to limit the viscosity of the adhesive
through lowered H-bonds between caseinates; sodium silicate to extend working life, tannate or
alkali tannate to increase adhesion.
Nowadays, casein glues, supplanted by synthetic glues in exterior woodworking, are still used in
labeling adhesives, in the bottling industry, in interior woodworking (plywood, door panels,
Formica laminates…), in bonding paper or in pressure sensitive adhesives.

24. Casein as a coating or sizing agent
In such utilizations, casein acts as a binder for the coating material, generally a
mixture of mineral materials, which is applied as a thin layer on the surface of the
material.
Paper industry
The hydrophobic/hydrophilic balance of casein increases its affinity for pigments,
its ink-binding properties and its adhesion to various substrates. In the paper
industry, casein is used as size for high quality glazed papers or for fine halftone
illustrations. Water resistance can be achieved by exposure to formaldehyde
vapors or by dipping in concentrated solutions of formaldehyde.

25. Textile industry
Caseins combined with acrylates become a protective coating against greying of
cotton. Chemically-modified caseins, either grafted with acrylate esters or cross-
linked, are used as anti-static finishing of natural (wool, cotton and silk) [49] and
synthetic (polyester) textile fibers.
Leather industry
Polyol plasticised casein is used in the finishing operations in the leather industry
combined with additional components such as acrylates, phenol derivatives, pigments
for coloured products or binders such as gelatine or sulfonated castor oil. The solution
is coated on the leather before the surface is mechanically processed (brushed,
ironed, glazed…).

26. Rigid casein plastics
Rigid plastic based on rennet casein is one of the best-known examples of nonfood
application for milk protein. Rennet casein and fillers are mixed with 20–35% water
before being mechanically processed by high pressure extrusion into plastic goods,
which are cured for a period of several days in a dilute solution of formaldehyde.
Paints
Because of its solubility and ability to bind pigments, caseinate has found applications
in water-based paints. Caseinate’s emulsifying properties make it a good stabilizer and
emulsifier in oil and latex paints. Its content in such for mulas does not exceed 1 to
2%.

27. Concrete and cement
For its adhesive and emulsifying properties, caseinate is used (or claimed so) in
concrete formulation in Eastern Europe, as well as cement, asphalt and bitumen.
Cosmetics
Caseinate is used as surface active agent in soaps and various cosmetics such as
cold wave lotions, hair sprays and hand cream. Casein hydrolysates could also be
active substances for skin hydration. However, little information is available about
these applications and their markets, which seem rather limited.

28. REFERENCES
Abreu D.(1945) Specific Gravity of milk and milk products J.Anim Sei. 69:2395:2402
Agger (1981): Bacterial count of raw milk in farm and storage tanks
Preventive veterinary medicine. 29(2):135-149.
Barbuddhe S B and Swain B K (200s) : Hygienie Preduction of Milk.
Technical Bulletin No: II. ICAR
Cruickshank eal 1975 Physical propeny of milk. Intemational J. food micro biology, 85(3):269-279
Mishra etal (1977): Flarour of milk Ing. J Diary Sci4912): 73-77
"OMFED" manual
Road house and Koestler (1929): Physical properties of milk. Text books of milk bacteriology
Singh 1963, 1968 Flavour of milk. Mol. Biochem Vet. Med 63:345-356.
Wikipedia

29. THANK
YOU