Nutritive value of milk;

Nutritive value  of milk;

Milk is an almost ideal food.

It has high nutritive value.

It supplies body-building proteins, bone-forming minerals and healthy –giving vitamins and furnishes energy-giving lactose and milk fat.

Besides supplying certain essential fatty acids, it contain the above nutrients in an easily digestible and assimilable form

All these properties make milk an important food for pregnant mother, growing children, adolescents, adults, invalids, convalescents and patients alike.

•  Proteins: Milk proteins are complete proteins of high quality , i.e. they contain all the essential amino-acids  in fairly large quantities

• Minerals: Pratically all the minerals elements found in milk are essential for nutrition.  Milk is an excellent source of calcium and phosphprus , both of which , together with vitamin D,  are essential for bone formation. Milk is rather low in iron, copper and iodine.

• Vitamins: These are accessory food factors which are essential for normal growth, health and the reproduction of living organism. Milk is a good source of vitamin A (provided the cow is fed sufficient green fed and fodder), vitamin D ( provided the cow is exposed to enough sunlight ), thiamine, riboflavin, etc . However , milk is deficient in vitamin C.

•  Fat: Milk fat (lipid) plays a significant role in the nutritive value , flavor and physical properties of milk and milk products. Besides serving as a rich source of energy, fat contains significant amount of so-called essential fatty acids (linoleic and arachidonic) . The most distinctive role which milk fat plays in dairy products concerns flavor. The rich pleasing flavor of milk lipids is not duplicated by any other types of fat. Milk fat imparts a soft body, smooth texture and rich taste to dairy products. Lastely , milk lipids undoubtedly enhance the consumer acceptability of food, They also serve the best interests of human nutrition through the incentive of eating what taste good.

• Lactose: The principal function of lactose(Carbohydrates) is to supply energy. However , lactose also helps to establish a mildly acidic reaction in the intestine ( which check the growth of proteolytic bacteria) and facilitates assimilation.

• Energy value: The energy- giving milk constituents and their individual contribution are as fallows:

Milk fat  9.3C/g

Milk protein  4.1 C/g

Milk sugar  4.1 C/g

Where 1 C ( Food calories) =1000c(small calories).

Note: The energy  value of milk will vary with its composition. On average , cow milk furnishes 75 C/100g and buffalo milk 100 C/ 100g.

• Effect of processing: (i) Pasteurization carried out with reasonable care has no effect on vitamin A, carotene,riboflavin and a number of remaining vitamins B, and vitamin D. Of  the reminder , a 10 per cent loss of thiamine and a 20 per cent  loss of ascorbic acid may be expected .(ii) Sterilization increase the losses of thiamine and ascorbic acid to 30-50 per cent respectively, through the remaining vitamins are but little affect.

 A balanced diet is essential for proper health and growth. The role of milk and milk products in providing the nutrients required for a balanced diet is indicated in table

 

Table                    

 

Role of milk and milk products in a balanced diet

Nutrients	Purpose	Sources
Proteins	Essential for muscle building and repair; give the body energy and heat	Meat, poultry, fibush,milk,cheese,beans,peas,nuts
Carbohydrate	Body energy and heat	Bread, cereals, pastry,sugar, vegetables, fruit
Fats	Body energy and heat	Butter, ghee, oils
Minerals	Bone, teeth, body cells	Dairy products, fruit, vegetables
Vitamin A	Growth , health of the eyes, structure and function of the skin and mucous membrane	Fat-rich dairy products, egg, spinach, carrot, tomatoes, fish liver oil
Vitamin B 1(Thiamine)	Growth, aids appetite , prevents beri-beri, function of nervous system	Whole grains, eggs, green vegetables, yeast, liver,kidney
Vitamin B2  (Riboflavin)	Growth , health of skin and moth, functioning of the eyes	Milk, cabbage, carrots, spinach,liver, eggs,yeast, lean meat, prones
Niacin	Functioning of the stomach , intestine and nervous system	Meat, heart, kidney, liver, eggs, fish, milk, peanuts, yeast
Vitamin C	Aids bones and teeth, prevent scurvy	Citrus fruit, maiz, tomatoes, lettuce, cabbage
Vitamin D	Aids in calcium- absorption which strengthens bones, prevent rickets	Egg, milk, fish liver oil

References:

Clarence Henry Eckles, Willes Barnes Combs, Harold Macy (1943). Milk and milk products, 4th Ed. McGraw-Hill book Company, Incorporated.

Sukumar. De (2001). Outlines of Dairy Technology. 1st Ed. Oxford University Press Delhi.