Beta-casein in involved in micelle formation. Caseins are the predominant milk proteins in most mammals. Casein, a 209 aa protein, yields three short peptides after cleavage: casoparan (5 aa), antioxidant peptide (8 aa) and casohypotensin (8 aa). Casoparan acts as a macrophage activator and a bradykinin-potentiating peptide. Casohypotensin acts as a bradykinin-potentiating peptide and a strong competitive inhibitor of endo-oligopeptidase A. The antioxidant peptide has antioxidant activity. Bovine milk casein is mainly found as alpha-s1, alpha-s2, beta, and kappa subunits ranging from 19-25 kDa.