- May 03, 2017 -
Whey protein is a mixture of globular proteins isolated from whey, the liquid material created as a by-product of cheese production.
Whey protein is commonly marketed as a dietary supplement, and various health claims have been attributed to it in the alternative medicine community.Although whey proteins are responsible for some milk allergies, the major allergens in milk are the caseins.
Whey is left over when milk is coagulated during the process of cheese production, and contains everything that is soluble from milk after the pH is dropped to 4.6 during the coagulation process. It is a 5% solution of lactose in water, with some minerals and lactalbumin.The fat is removed and then processed for human foods.Processing can be done by simple drying, or the protein content can be increased by removing lipids and other non-protein materials. For example, spray drying after membrane filtration separates the proteins from whey.
Whey can be denatured by heat. High heat (such as the sustained high temperatures above 72 °C associated with the pasteurization process) denatures whey proteins. While native whey protein does not aggregate upon renneting or acidification of milk, denaturing the whey protein triggers hydrophobic interactions with other proteins, and the formation of a protein gel. Heat-denatured whey can still cause allergies in some people.