All butter comes from dairy cows. It is a yellowish white mixture of fat, water, and the inorganic salts created when cow’s milk or cream is churned into butter. Butter contains largely Vitamin A, plus small amounts of calcium and phosphorus. Carotene gives it the yellowish-white pigment. (In the United States, manufacturers are allowed to add vegetable color to make butter more yellow.)
Butter in the United States is made under strict FDA regulations. Fresh milk is first inspected for weight, quality, and milkfat levels. The cream is then separated and pasteurized with at least 161? heat for about 15 seconds. Ultra-pasteurized milk is heated to at least 280 for 2 seconds. This extreme heat kills bacteria and gives the butter more shelf life. After pasteurization is complete, the cream is churned until it is solid: butter. The butter is then packaged and ready to be shipped to market.
All butter is considered food; it must contain at least 80% milkfat to be considered butter. There are three different types:
- Lightly salted butter is used primarily for basic cooking. It usually comes in pre-measured sticks.
- Unsalted butter is preferred for baking and for people on salt-restricted diets. It too usually comes in pre-measured sticks.
- Whipped butter, made by whipping air or nitrogen into soft butter, makes spreading more convenient. It usually comes in tubs.