Influence of Transglutaminase Treatment on Proteolysis and Lipolysis of Low-Fat White-Brined Cheese Incorporated with Whey Proteins during Ripening

Fat reduction adversely affects different properties of cheese. Transglutaminase treatment of low-fat milk incorporated with whey proteins makes it possible to develop a low-fat white-brined cheese with rheological properties similar to the full-fat counterpart. The objective of this study was to monitor the changes in proteolysis and lipolysis indices of transglutaminase–treated low-fat white-brined cheese during ripening. A control full-fat (3% fat), a control low-fat (1% fat) and an enzyme-treated low-fat (1% fat, 0.9 U transglutaminase/g protein, 5% whey protein isolate/L milk) white-brined cheese were produced and their physicochemical properties, proteolysis and lipolysis indices, FFA profile and organoleptic attributes were studied after 3, 20, 40 and 60 days. The proteolysis and lipolysis indices of all samples showed an increasing trend during ripening (p<0.05). The development of proteolysis and lipolysis in white-brined cheese with reduced fat content was noticeably slower than its full-fat counterpart (p<0.05). Transglutaminase treatment of low-fat milk incorporated with whey proteins retarded the syneresis of resultant cheese and hereby promoted its extent of proteolysis and lipolysis (p<0.05). The decreasing rate of short-chain free fatty acids production was more pronounced than that of medium- and long-chain free fatty acids, due possibly to their contribution to production of flavor compounds. Flavor of enzyme-treated low-fat cheese was considerably improved during ripening (p<0.05) but was less appreciated by consumers than that of control full-fat sample (p<0.05). Transglutaminase treatment of low-fat milk incorporated with whey proteins results in a low-fat white-brined cheese with accelerated proteolysis and lipolysis and thus, more desirable organoleptic properties.