What is Milk?
Normal Definition
Milk is a white fluid food secreted by mammals through their mammary glands to feed their young ones, in order to provide nutrition for their growth.
Standard Definition
Milk may be defined as whole, fresh, clean, lacteal secretion obtained by the complete milking of one or more healthy milch animals, excluding that obtained within 15 days before or 5 days after calving or such periods as may be necessary to render the milk practically colostrum free and containing the minimum prescribed percentage of milk fat and milk solid-not-fat (SNF).
In India, the term ‘milk’, when unqualified, refers to cow or buffalo milk, or a combination of the two.
Chemical Definition
In chemical terms, milk may be defined as a complex chemical substance in which fat is present in the form of an emulsion, protein, and some mineral matter in the colloidal state, and lactose with some minerals and soluble proteins in the form of true solution.
Constituents of Milk
The constituents of milk may be divided into two categories:
(a) Major constituents
(b) Minor constituents
Major constituents of milk include water, fat, protein, lactose, ash, or mineral matter.
Minor constituents of milk, constitute phospholipids, sterols, vitamins, enzymes, pigments, etc.
