Butter is a dairy product that contains up to 80% butterfat (in commercial products) which is solid when cooled and at room temperature in some regions and liquid when heated. It is made by whipping cream or fresh or fermented milk to separate butterfat from buttermilk. In general, it is used as a spread product on toasted or smooth bread and as a seasoning in cooked vegetables, as well as in the kitchen, such as baking, making sauce and frying in frying pan. Butter consists of butterfat, milk proteins and water, and in some types, added salt. Butter can also be sold with added flavourings, such as garlic butter.
Most often made from cow's milk, butter can also be made from the milk of other mammals, such as sheep, goats, buffalo and yaks. Sometimes salt such as milk salt, flavourings and preservatives are added to the butter. The production of butter produces clarified butter or ghee, which is almost entirely butterfat.
Butter is a water-in-oil emulsion that results from an inversion of the cream; in a water-in-oil emulsion, the milk proteins are the emulsifiers. The butter remains solid when cooled, but softens to a roomable consistency at room temperature and melts to a thin liquid consistency at 90-95 ° F (32-35 ° C). The density of the butter is 911 g / L (0.950 lb per US pt). It usually has a pale yellow colour, but varies from intense yellow to almost white. Its unmodified colour is dependent on feed and genetics of animals, but is commonly handled with food colourings in the commercial manufacturing process, most commonly achiote or carotene.