Milk

About milk
Milk is an opaque white liquid produced by the mammary glands of mammals, most commonly cows, goats, sheep, water buffalo and yaks. It provides the primary source of nutrition for young mammals before they are able to digest  other types of food. The early lactation milk is known as colostrum, and carries the mother's antibodies to the baby. It can reduce the risk of many diseases in the baby. The exact components of raw milk varies by species, but it contains significant amounts of saturated fat, protein and calcium  as well as vitamin C. Cow's milk has a pH ranging from 6.4 to 6.8, making it slightly acidic.

By fat content
The terminology for different types of milk, and the regulations regarding labelling, varies by country and region.

Canada

 * Whole milk – creamline (unhomogenized) milk
 * Homogenized milk – 3.25% butterfat (or milk fat)
 * Skimmed milk – 1%, and 2% milk fat milks

Generally all store-bought milk in Canada has been homogenized. Yet, the term is also used as a name to describe butterfat/milk fat content for a specific variety of milk. Modern commercial dairy processing techniques involve first removing all of the butterfat, and then adding back the appropriate amount depending on which product is being produced on that particular line.

United States

 * Whole milk – 3.25% butterfat content
 * 2% or Reduced fat milk – about 2%
 * Semi-skimmed – 1.5 – 1.8%
 * 1% or Low fat – about 1%
 * Skimmed milk – 0.0 – 0.5%

United Kingdom

 * Channel Island milk or breakfast milk – 5.5% butterfat content
 * Whole milk or full fat milk – 3.5%
 * Semi-skimmed – 1.5 – 1.8%
 * The One or 1% – 1%
 * Skimmed – Less than 0.3%