The document discusses milk and milk products. It defines milk and describes the quality control process during milk production. It explains pasteurization and homogenization. It then discusses various milk products like fluid milk, butter, concentrated/dried dairy products, cheese, and others. It provides details on the production processes for these different milk products.

1. MILK

2. Objectives
 Define the term “milk”
 Describe quality control during the production of milk and milk
products
 Explain pasteurization and homogenization
 Identify three methods of pasteurization
 Describe the “solids” composition of milk
 Discuss the separation of butterfat and its use
 List four beverage milk products
 Describe butter
 Name 5 concentrated or dried dairy products
 List the steps in the cheese making process
 Identify 3 bacteria used to produce dairy products
 Name 5 fermented dairy products
 List the steps in making and ice cream and make ice cream
 Describe the USDA quality grade shields

3. Introduction
 Milk: the first food for young mammals
 Provides high quality protein, vitamins and minerals and
is a source of energy
 Worldwide many mammilian species are used to
produce milk and milk products
 Goats, sheep, horses, yaks
 However, our focus will be on milk from dairy cows

4. Fluid Milk

5. Fluid Milk
 Collodial dispersion of the protein caesin and the
whey proteins. It is an emulsion with fat globules
suspeneded in the water phase
 Composed mainly of water
 87-89%
 Milk solids make up the other 12-13%
 Solids include the carbs, lactose, fat, protein
and minerals
 Solids-not-fat
 Excludes the fat and includes the caesin,
whey, lactose, proteins, minerals

6. Production Practices
 Fewer cows are producing more milk
 Daries are becoming larger
 In major production areas daries are 1,000 cows or more
 Milk fresh from the cow is virtually sterile
 Post handling must maintain the milks nutritional value
and prevent deterioration caused by physical and
biological changes
 Equipement must be maintained to government and
industry standards

7. Production Practices
 Cows are milked twice a day
 Some farms milk 3-4 times/day
 Milk is immediately cooled from the body
temperture of the cow to below 41 degrees F
 It is then stored at the farm under refrigeration
until it is picked up by tanker trucks at least
every other day
 A sample of the milk is collected at this time for later
lab analysis

8. Quality Control
 On the farm
 Inspectors monitor herd health, farm water supply,
sanitation, milk temperture, holding times, bacteria
counts
 Violations of health standards result in heavy penalties
up to and including suspension from business
 Inspections occur both at the farm and processing plants
on a regular on-going basis
 Inspectors have full authority to suspend plant
operations in order to conduct detailed examinations of
all equipment, facilities and products
 The dairy industry works hard to ensure that they comply
with or exceed all regulations

9. Quality Control
 Finished dairy products
 Tested regularly by state inspectors to ensure
compliance with
 Standards of Identity
 Refers to criteria such as mouisture, butterfat,
protein content
 Purity
 Refers to pathogens and residues criteria
 The Food and Drug Administration (FDA) sets the
standards of identity for beverage milk products

10. Processing
 When milk arrives at the plant it is checked to
make sure that it meets the standards for
temperture, total acidity, flavor, odor, tanker
cleanliness and absence of antibiotics
 Butterfat and solids-not-fat content is analyzed
 These amounts will vary with the feed, breed of cow
and time of year
 These are also used along with the volume to
determine what the producer will be paid
 Once the milk passes these receiving test it is
pumped into large refrigerated silos

11. Pasteurizing
 Heating the raw milk to kill all pathogenic
microoranisms that may be present
 Not sterilization
 After pasteurization some harmless bacteria
may still be present
 these are the bacteria that cause milk to go
sour
 Refrigeration is the best way to slow the
growth of these organisims

12. Pasteurizing
 Low Temperture Longer Time (LTLT)
 Heats milk to at least 145 degrees F for at least 30 minutes
 Can cause a “cooked” flavor
 Not used by some milk plants for fluid milk products
 High Temperture/Short Time (HTST)
 Heats milk to at least 161 degrees F for at least 15 seconds
 Milk is immediately cooled to below 40 degrees F and packaged
in plastic jugs or plastic coated cartons
 Ultrapasteurization
 Heating milk to 280 degrees F or higher for 2 seconds followed
by rapid cooling to 45 degrees or less
 Ultrahigh Temperture Processing
 Sterilizes the milk
 Heats it to 280-302 degrees for 2 to 6 seconds
 Milk is aseptically packaged and does not require refrigeration
until it is opened

13. Butterfat
 Several different types of product
 Whole milk, 2%, 1%, nonfat, Half & Half
 Seperated using separator that separates the
cream and skim portions of the milk
 For example: During the separation of whole
milk two streams are produced: the fat-depleted
stream, which the above mentioned beverage
milks are made of; skim milk for evaporation
and/or drying and the fat-rich stream, the cream

14. Butterfat: Cream
 Comes from the separator with a fat content of
35-45%
 Used for further processing in the dairy industry
—ice cream, butter

15. Homogenization
 Prevents the cream from rising to the top
 A “homogenizer” forces milk under high
pressuure through a valve that breaks up
butterfat globules to such a small size that they
will not coalesce (stick together)
 Does not affect the nutrion or quality

16. Beverage Milk
 Most raw milk fat content is 4% or higher
 Most beverage milk is 3.4%
 Lower fat contents- 2%, 1%, Skim
 These products are produced by partial or complete
skimming and then adding cream back to achieve the
final desired fat content

17. Nutritional Qualities
 Vitamins may be added
 A & D most often due to their loss
 A during fat separation and heating
 D because it is not present in milk
 Supplemeted in the form of a water-soluble
emulsion
 Many states have milk standards that require the
addition of milk solids
 These represent the natural mineral, protein, and
sugar portion of nonfat dry milk

18. Quality Control
 Numerous test on raw and paterurized product
 Microbial organisims are tested for using the standard
plate count (SPC) and ropey milk test
 Equipment used to analyze butterfat and solids-not-fat is
calibrated on a regular basis to ensure consistency
 All products have a sell-by date
 Samples of the products packaged each day are saved
to confirm they maintain their freshness 7 days after the
sell-by date

19. Packaging
 Once milk is separated, standardized, homogenized and
pasteurized it is held below 40 degrees F
 Then it is packaged into gallon, ½ gallon, quart, pint and half pint
containers
 Packaging machines are maintained under strict standards
 All equipment is washed daily
 Automatic clean-in-place systems guarantee consistent sanitation
with minimum manual handling to reduce the risk of contamination
 Once packaged the products are conveyored to cold storage where
they are stored for a short time before being shipped to
supermarkets where they are kept in cold storage or refrigerated
display cases

20. Milk Products and By-
Products

21. Milk Products and By-Products
 Include
 Butter
 Concentrated and dried milk
 Cheese
 Whey products
 Yogurt
 Fermented products
 Ice Cream

22. Butter
 Made by churning pasteurized cream
 Churning breaks up the fat globule membrane
 This breaks the emulsion, fat coalesces and the water
(buttermilk) escapes
 Federal law requires that it contain at least 80%
milkfat, nutritionally butter is a fat.
 Salt and coloring may be added
 Today commercial butter making is a product of
knowledge and experience gained over the
years

23. Butter Make-Up
 Normal Salted Butter
 Fat 80-82%
 Water 15.6-17.6%
 Salt 1.2%
 Proteins, Calcium, Phosphorous 1.2%
 Also contains fat soluble vitamins A, D, E

24. Butter
 Should have uniform color
 Be dense
 Taste clean
 Water should be dispersed in fine droplets so
that the butter looks dry
 Consistency should be smooth so that it is easy
to spread and melts readily on the tongue

25. Making Butter
 From storage tanks the cream goes to pasteurization
 This destroys enzymes and microorganisms that would impair the
keeping quality of the butter
 Next, ripening
 Here the cream is subject to a program of heat treatments designed to
give the fat the necessary crystaline structure so it solidifies on cooling
 Takes 12-15 hours
 Churning
 Cream is violently agitated
 This breaks down the fat globules, causing the fat to coagulate into butter
grains, leaving the liquid part (buttermilk)
 Butter is salted and worked to ensure even distribution
 Packaged
 Sent to cold storage

26. Concentrated and Dried Dairy
Products
 Concentrated products have partial water
removal
 Dried products have water removed to less than
4%
 Benefits of both products are
 Increased shelf life
 Convenience
 Product flexibility
 Decreased transportation costs
 Storage

27. Concentrated and Dried Dairy
Products
 Concentrated Products  Dried Products
 Evaporated skim or  Milk Powder
whole milk  Whey Powder
 Sweetened condensed  Whey Protein
milk concentrates
 Condensed buttermilk
 Condensed whey

28. Cheese
 Traditionally cheese was made as a way of
preserving the nutrients of milk
 Cheese- the fresh or ripened product obtained
after coagulation and whey seperation of milk,
cream, or partly skimmed milk, buttermilk or a
mixture of these
 THOUSANDS of varieties

29. Cheese Making Steps
 Treat milk
 Additives
 Inoculation and milk ripening
 Coagulation
 Enzyme
 Acid
 Heat-acid
 Curd Treatment
 Cheese ripening