Dairy Products

1
Dairy Products

• Milk and Cheese

2
Milk

• Products of milk (dairy products)
• Butter
• Cream
• Cheese

3
Milk

• Types of milk
• Untreated
• Pasteurised
• Homogenized
• Sterilized
• Ultra-high temperature (UHT)
• Evaporated
• Condensed
• Powdered
• Skimmed

4
Milk

• Types of milk
• Untreated milk
• has not gone through any kind of heat treatment
• bottled on the farm
• 2. Pasteurized milk
• given mild heat treatment (72C for 15 seconds)
  to destroy most disease-carrying germs

5
Milk

• Types of milk
• 3. Homogenised milk pasteurised milk processed
  to disperse the fat globules and distribute them
  evenly throughout the milk
• 4. Sterilised milk homogenised milk heated to a
  high temperature (113C) for 15 40 minutes

6
Milk

• Types of milk
• 5. Ultra-high temperature (UHT) milk homogenised
  milk heated to a high temperature of 132C for
  not more than one second
• - can be kept for months without
  refrigeration

7
Milk

• Types of milk
• 6. Evaporated milk some water has been removed
  from the milk through evaporation
• - contains 25 less water than fresh milk
• - sterilised at 115.5C for 20 minutes
• 7. Condensed milk some water has been removed
  from milk through evaporation
• - sweetened with sugar

8
Milk

• Types of milk
• 8. Powdered milk all water has been removed
  (powder form)
• 9. Skimmed milk fats have been skimmed off the
  milk

9
Nutritive Value of Milk

• Proteins
• High biological value
• Caseinogen (80), lactalbumin, lactoglobulin
• 2. Fats
• In the form of very tiny droplets dispersed
  throughout the milk (emulsion)
• Milk fats are used in the production of cream and
  butter

10
Nutritive Value of Milk

• 3. Carbohydrate
• In the form of lactose (milk sugar)
• 4. Vitamins
• A, D, B1, B2
• 5. Minerals
• Calcium
• Phosphorus
• Sodium
• Chlorine
• Potassium
• 6. Water 87

11
Effect of Heat on Milk

• When milk is boiled, proteins coagulate and form
  a layer on the surface.
• As boiling continues, hot air and steam get
  trapped under this layer.
• This results in milk overflowing from its
  container.

12
Cheese

• A concentrated form of milk
• It is a means of preserving nutritive value of
  milk

13
Types of Cheese

1. Very hard cheese water content is 30 32
   (Parmesan cheese grated for sprinkling on cooked
   food)
2. Hard cheese water content is 37 40 (Cheddar
   cheese grated for use in cooking)
3. Soft cheese water content is 50 (Cream cheese,
   processed cheese and cottage cheese used as
   spreads on biscuits and for cheesecakes)

14
Nutritive Value of Cheese

• Contains practically all the nutrients found in
  milk EXCEPT carbohydrates
• Lactose in milk is converted into lactic acid
  during the manufacturing of cheese

15
Effect of Heat on Cheese

• When cheese is heated, the fat melts and
  separates.
• Cheese becomes soft.
• On further heating, proteins over-coagulate and
  become stringy and tough.