INFLUENCE OF GENETIC-VARIANTS OF KAPPA-CASEIN AND BETA-LACTOGLOBULIN IN MILK ON PROTEOLYSIS IN CHEDDAR CHEESE

Effects of genetic variants of K-casein (A or AB) and beta-lactoglobul in (A, AB or B) in milk on proteolysis in Cheddar cheese were evaluate d. Average water-soluble nitrogen levels (expressed at % total nitroge n) in the cheeses did not depend, significantly (p > 0.05), on genetic types of kappa-casein or beta-lactoglobulin. However, qualitative dif ferences were noted in the electrophoretic patterns of the cheese made from kappa-CN AA or AB milks. Similarly, electrophoretic patterns or HPLC profiles of peptides in the water-soluble extracts from kappa-cas ein AA cheeses were different from those from kappa-CN AB cheeses. The results suggest that proteolytic enzymes In cheese may have different specificities towards milk protein variants during cheese ripening.