Proteolysis in goats’ milk cheese made with calf rennet and plant coagulant

Primary proteolysis, secondary proteolysis and changes in hydrophilic (HI) and hydrophobic (HO) peptides during ripening of a goats’ milk cheese (Murcia al Vino) manufactured with either plant coagulant (PC) or calf rennet (AR) were studied. In the Murcia al Vino cheese, intense proteolytic activity took place during ripening, and after a 60-day ripening period of the cheeses made with animal rennet, values of 19.04, 9.61, 0.55 and 0.66 for water-soluble nitrogen (WSN) at pH 4.6, non-protein nitrogen (NPN), ammonia nitrogen (NH3N) and amino acid nitrogen (AAN), were obtained. In the cheeses produced with PC, proteolysis was more intense, and after 60 days of ripening, values of 34.79, 11.16, 0.59 and 0.88 for WSN, NPN, NH3N and AAN were obtained. Casein (CN) proteolysis was more intense in cheeses manufactured with PC, compared with those manufactured with AR. β-CN degradation products (γ-CN fractions) were higher in cheeses manufactured with AR. HI and HO concentrations and the HO/HI ratio was higher in cheeses made with PC. These results were further confirmed by principal component analysis (PCA). The use of PC for goat cheese manufacture might accelerate ripening and, thus, a cheese with different sensory characteristics caused by increased cyprosin proteolytic activity may be obtained.