Opioid peptides encrypted in intact milk protein sequences

Opioid agonistic and antagonistic peptides which are inactive within the se quence of the precursor milk proteins can be released and thus activated by enzymatic proteolysis, for example during gastrointestinal digestion or du ring food processing. Activated opioid peptides are potential modulators of various regulatory processes in the body. Opioid peptides can interact wit h subepithelial opioid receptors or specific luminal binding sites in the i ntestinal tract. Furthermore, they may he absorbed and then reach endogenou s opioid receptors.