Effects of commercial enzymes on proteolysis and ripening in Cheddar cheese

The effects of exogenous enzyme preparations, ie FlavourAge-FR or DCA 50, on proteolysis flavour texturai development in high (38%) or low (35%) moisture Cheddar cheeses ripened at 4 or 10°C for 180 days were investigated. Proteolysis, as measured by nitrogen soluble in water (WSN), 75% ethanol (ALC-N) or 5% PTA (PTA-N), was highest in cheeses with added FlavourAge-FR, intermediate in DCA 50-treated cheeses and lowest in control cheeses at both 4 or 10°C. The WSN was chromatographed by fast protein liquid chromatography (FPLC) and free amino acid analysis. The concentrations of low molecular weight (< 10000) peptides and free amino acids were highest in FlavourAge-FR-treated cheeses while DCA 50-treated cheeses had intermediate levels compared to control cheeses at 4 or 10 oC. Polyacrylamide gel electrophoresis of the cheeses during ripening showed that FlavourAge-FR caused significant proteolysis of both α51- and p-caseins, while DCA 50 caused no significant degradation of p-casein. Cheese texture, as measured by yield value, was affected most by FlavourAge-FR treatrnent. Taste panel analysis of the cheeses indicated Iittle acceleration of flavour development by any of the treatments, and in some cases enzyme treatment led to off-flavours and textural defects.