Milk is a white liquid produced by the mammary glands of mammals. It is the prime source of nutrition it has colostrums that help to reduce the risk of many dieses in all ages of human beings. Milk derived from cattle is an important food. It has many nutrients. The precise nutrient composition of raw milk vary by species and by a number of other factors, but it contains significant amounts of saturated fat, protein and calcium as well as vitamin C.