Casein is the name for a family of related phosphoproteins (αS1, αS2, β, κ). These proteins are commonly found in mammalian milk, making up 80% of the proteins in cow milk and between 20% and 45% of the proteins in human milk. Casein has a wide variety of uses, from being a major component of cheese, to use as a food additive, to a binder for safety matches. As a food source, casein supplies amino acids, carbohydrates, and two inorganic elements, calcium and phosphorus.
Casein is used in Production and characterization of a phage-display recombinant antibody against carrageenans: evidence for the recognition of a secondary structure of carrageenan chains present in red algae tissues.
Partial gastrointestinal digestion of casein is a rich source of bioactive peptides, such as β-casomorphin. However, bovine casein is not homogeneous; variants A1 and B do lead to production of β-casomorphin 7 production, while A2 does not.