Characteristics and potential uses of the casein macropeptide

Abstract

The casein macropeptide (CMP) is a heterogeneous fraction of peptides formed by the action of rennet on casein and more specifically κ-casein. This fraction has unique composition and characteristics. Several methods have been developed for the determination of CMP in order to follow the action of chymosin on milk and κ-casein or to detect the presence of whey solids in milk powders. The CMP or its tryptic digest was reported to have diverse biological activities and some of these have been used as a base for medicinal preparations. Also, the unique amino acid composition and functional properties of the CMP suggest that it can be incorporated in some dietetic foods. Methods based on ion exchange chromatography and ultrafiltration have been used for large-scale preparation of CMP with either chymosin-treated casein, caseinates or rennet whey as a starting material.