Nutritive value of milk:
Milk is not only used as such but many products, non – fermented and fermented are used in cookery. About 30 – 50% of the total milk production in the country is converted to milk products.
Nutritive value of milk:
Milk has good quality protein, and the biological value is over 90. Though milk contains only 3-4% protein, due to the quality of protein and the amount that can be ingested, and the presence of other nutrients makes it indispensable. Lysine is one of the essential amino acids which is abundant in milk proteins. Cheese, khoya and dehydrated milk powders are in concentrated forms hence contain high amount of nutrients per unit.
Milk is the only substance that contains lactose, which has Galactose which is essential for the synthesis of myelin sheath. Lactose, not been easily soluble favours the growth of lactic acid bacillus in the intestine, which decreases the PH. This drops in pH favour calcium absorption. Lactose also increases the permeability of the small intestine for calcium ions. Milk sugar due to its controlled glycaemic effect, is preferred as a source of carbohydrate.
The fat of milk is easily digestible. It contains linoleic acid 2.1%, linolenic acid 0.5%, arachidonic acid 0.14%. Skimmed milk does not contain any fat. Buffalo milk contains high amount of fat.
Dairy foods are a major source of calcium because of the significant amount of the minerals present. The calcium -phosphorus in milk is regarded as most favourable for bone development. Dairy products contain other nutrients such as vitamin d and lactose which favour calcium absorption.
Milk is a poor source of iron. But whatever little ironies present it is utilised in the body. Khoya contains more amount of iron as it gets from the containers during the whole process. Milk has been an important dietary source of preformed vitamin A, but many urban residents consume Dairy Milk from which much of the vitamin has been removed with a fat. Milk produced by government of Tamil Nadu is fortified with 1000 IU for every 500 ML of milk.
Time in occurs in only fair concentration in milk but is relatively constant in amount. Riboflavin is present in a higher concentration in milk than the other B – vitamins and its stability to heat makes milk a dependable source of this vitamin. In cheesemaking, riboflavin is present in whey water. Since it is sensitive to light, when milk is exposed to sunlight 50% of riboflavin is lost. Milk is not a good source of niacin, but it is an excellent source of tryptophan. Milk is a very poor source of vitamin see the amount of vitamin A and D depends upon the feed of the animal. Milk is a complex mixture of lipids, carbohydrates, proteins and many other organic compounds and inorganic salts dissolved or dispersed in water. Casein and whey are the proteins which are found in milk.
Some examples of milk products are:
- Dry milk
- Sweetened condensed milk
- Khoya
- Ice – cream
- Rabri
- Sour cream etc.