The interaction of phospholipase and transglutaminase enzymes in pasta filata cheese production and its effect on yield, composition and textural properties

For industrial cheese producers, maximizing cheese yield without compromising product quality is crucial for operational profitability. This study examined the effects of adding transglutaminase and phospholipase-A1 enzymes to pasta-filata cheeses produced by different methods in order to enhance cheese yield. The impact of transglutaminase and phospholipase-A1 enzymes, both together and separately, on the yield of Kashar and Mengen cheeses, which involve fermentation and scalding processes at different temperatures, was determined. These enzymes were added before, simultaneously with, and after the rennet enzyme (coagulation), both together and separately, and the produced cheeses were evaluated in terms of basic composition, yield, and microstructure. The sole use of the phospholipase-A1 enzyme showed a tendency to increase the fat content in the cheese, but this increase was not statistically significant (p˃0.05). Protein values increased in all samples where the enzymes were added after the rennet enzyme (p˂0.05), and the highest increase was obtained when both enzymes were added post-rennet. Significant increases in dry matter values were also identified in samples where both enzymes were added together and separately after the rennet enzyme. Yield increased in parallel with the dry matter values. However, the fat separation values did not depend on the fat content but varied according to the timing of the addition of the phospholipase-A1 and transglutaminase enzymes. It was determined that fat separation was higher in the samples where the enzymes were added post-rennet. When transglutaminase was added post-rennet and phospholipase-A1 was added pre-rennet, the textural properties of the Mengen and Kashar cheese samples obtained firmer textures. The role of enzymes is significant when it comes to microstructure. The addition of only phospholipase-A1 resulted in a more pronounced granular structure, while transglutaminase closed the voids and pores, forming a matrix structure. However, when both enzymes were present, a granular and dense structure was observed, indicating the combined effect of the enzymes on the cheese's microstructure. As a result, the simultaneous addition of both transglutaminase and phospholipase-A1 enzymes with the rennet enzyme led to a 1.1% increase in yield for Mengen cheese and an average of 1% for Kashar cheese. The addition of these enzymes after the rennet enzyme increased fat separation.