Rennet is an aspartic protease first found in the stomach of pre-weaned calves. It specifically cleaves the peptide bond between Phe105-Met106 of κ-casein in milk and destroys casein micelles. Rennet’s milk-clotting, clotting and proteolytic abilities make it an important enzyme in the formation of texture and special flavors in cheese making. It is often used to make cheese and yogurt.