Where Does Butter Come From?
Butter is made through the process of churning milk or cream. Milk is full of tiny drops of butterfat. Butter is made from this fat. Cream is the part of milk that is richest in butterfat. In a churn, the milk or cream is stirred rapidly. While it is being churned, the drops of fat join together into lumps of butter.
The milky liquid remaining after the butter has been taken out is called “buttermilk.” Most butter is made from cow’s milk. But butter can be made from the milk of other animals. In many countries butter comes from the milk of goats or sheep.
It is generally used as a spread on plain or toasted bread products and a condiment on cooked vegetables, as well as in cooking, such as baking, sauce making, and pan frying. Butter consists of butterfat, milk proteins and water.
Butter is a water-in-oil emulsion resulting from an inversion of the cream; in a water-in-oil emulsion, the milk proteins are the emulsifiers. Butter remains a solid when refrigerated, but softens to a spreadable consistency at room temperature, and melts to a thin liquid consistency at 32–35 °C (90–95 °F). The density of butter is 911 g/L (0.950 lbs per US pint).
It generally has a pale yellow color, but varies from deep yellow to nearly white. Its unmodified color is dependent on the animals’ feed and is commonly manipulated with food colorings in the commercial manufacturing process, most commonly annatto or carotene.
Commercial butter is about 80% butterfat and 15% water; traditionally made butter may have as little as 65% fat and 30% water. Butterfat is a mixture of triglyceride, a triester derived from glycerol and three of any of several fatty acid groups. Butter becomes rancid when these chains break down into smaller components, like butyric acid and diacetyl. The density of butter is 0.911 g/cm3 (0.527 oz/in3), about the same as ice.