Application Casein from bovine milk is a phosphoprotein. There are four main types of Casein which make up approximately 80% of the total protein in bovine milk: α-s1 Casein, α-s2 Casein, β-Casein, and κ-Casein. Casein is proposed to be the main protective constituent in milk
Biochem/physiol Actions 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.