What is the term for the fat found in cow's milk?

The term for the fat found in cow's milk is butterfat. Butterfat, also known as milkfat, is a significant component of milk that contributes to its creamy texture and rich flavor. It is a mixture of various fats, primarily triglycerides, and makes up about 3.5% to 5% of whole milk, although this percentage can vary.

Butterfat plays an essential role in dairy products such as butter, cream, and flavored yogurts, where its presence is crucial for achieving desirable taste and texture. In addition to its contributions to flavor, butterfat also provides essential fatty acids and calories, making it an important nutrient component of milk.

The other choices refer to different components of milk with distinct functions. Protein refers to the general group of nutrients that include various forms found in milk, while casein is one specific type of protein that forms the basis of cheese and is a major protein in cow's milk. Lactose, on the other hand, is the sugar found in milk, which serves as a carbohydrate source. Each of these components plays a role in the overall nutritional profile of milk, but they are not related to the fat content specifically.