Physicochemical characteristics of set yoghurt made with sodium caseinate and transglutaminase

This study evaluated the effect of Transglutaminase activity (0-3 u/g protein), sodium caseinate content (0-0.6%) and enzyme reaction time (60-180 min) on acidity, syneresis, fermentation time and protein cross-linking in set yoghurt using response surface methodology (RSM). Syneresis was analyzed with siphon method. It decreased with an increase in Transglutaminase activity up to 0.6 (u/g protein). Treating with Transglutaminase also induced reductions in monomeric caseins (αs1-, β-, and κ-caseins) contents and formation of high-molecular weight polymers. Acidity did affect by the all treatments used but had not under regular procedure. Fermentation time did not affected by enzyme activity but increased by an increase in sodium casein ate content from 0.6 to 1.2