MILK is the normal mammary secretion derived from complete milking of healthy milch animal. It is also defined as the whole, clean, fresh, lacteal secretion obtained by complete milking of one or more healthy milch animals. Milk has been evolved as an ideal source of nourishment to the young ones of a particular species producing it. In many parts of the world, cow is the major source of milk for human consumption. However, some other sources of milk like buffalo, goat, sheep, camel etc have also been employed for milk consumption.