Butterfat or milkfat is the fatty portion of milk. Milk and cream are often sold according to the amount of butterfat they contain. According to studies by an independent dermatologist, butterfat has been found to have skin moisturizing qualities.
The fatty acids of butterfat are typically composed as follows (by mass fraction):
Fatty acids v triglycerides
As shown above, the composition of fats in milk is usually discussed in terms of the fatty acids. Fatty acids do not occur as such in milk (and rarely in any food). Instead, they are incorporated into compounds called triglycerides.
In the U.S., there are federal standards for butterfat content of dairy products. Many other countries also have standards for minimum fat levels in dairy products. Commercial products generally contain the minimum legal amount of fat with any excess being removed to make cream, a valuable commodity.
- Frozen desserts
- Butter (including whipped butter) contains at least 80% fat
- National Research Council, 1976, online edition Fat Content and Composition of Animal Products, Printing and Publishing Office, National Academy of Science, Washington, D.C., ISBN 0-309-02440-4; p. 203
- The quote values vary by 1-3% according to the source: Rolf Jost "Milk and Dairy Products" Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2002. doi:10.1002/14356007.a16_589.pub3
- United States Department of Agriculture Agricultural Marketing Service
- USDA Commercial Item Description: Milks, Fluid (2001).
- USDA Specifications for Cream Cheese, Cream Cheese with other Foods, and Related Products (1994).
- United States Department of Agriculture Standard for Ice Cream (1977).
- USDA Commercial Item Description: Cream, Eggnog, Half-and-half, and Sour Cream (2002).