Comparative Study on the Effect of Adding Transglutaminase to Cow’s Milk on the Properties of Low-Fat Gouda-Like Cheese

Three batches of Gouda - like cheese were prepared from whole fat (3.5% fat), reduced fat (2.5% fat) and low fat milk (1.5% fat). Another three batches were similarly made with the addition of Transglutaminase (TGase) at a rate of 0.5 g/ liter (50 unit) of milk to study the effect of enzyme on the quality of Gouda - like cheese with three levels of fat content. The obtained results showed that addition of enzyme , markedly increased the moisture content of treated milk cheese as compared with the control. The highest moisture contents for fresh and ripened cheese were found in low- fat cheese treated with the enzyme. The addition of enzyme to cheese milk led to slight decrease in fat content of the fresh and ripened cheese, while an increase in total protein content was detected for all treatments. Reducing fat content (2.5 or 1.5%) of cheese milk reduced the ripening indices (WSN, NPN, PTA-SN and TVFA) of the resultant cheeses comparing with the control. On the other hand, addition of the TGase, markedly increased the values of all ripening indices including the whole milk cheese. The addition of TGase, showed slight effect on either decreasing the acidity or raising the pH values. Reducing fat content of cheese milk lowered the enumeration of viable total bacterial counts, lipolytic and proteolytic bacteria. The incorporation of TGase increased the three bacterial groups during the first month of ripening and continued for lipolytic and proteolytic bacteria up to the end of ripening period, while TC decreased after the first month. The addition of the TGase, highly improved the organoleptic properties of the three groups of cheese.