The effect of microbial transglutaminase and two different starter cultures on goat milk yogurt

In this study, we produced goat milk yogurts with mTGase (microbial transglutaminase), two different yogurt starter cultures (the non-EPS producer YC350 and the EPS producer YoFlex), and casein powder for fortification. The research design was based on response surface methodology and testing independent variables such as pH, lactic acid percent, and relative viscosity. Four yogurts were produced and tested. In organoleptic evaluation, yogurts produced with YC350 scored higher in odor and taste. The SDS-PAGE patterns showed that monomer band intensity decreased with higher mTGase concentrations. The best microstructure was in yogurt made with the highest mTGase and EPS producer bacteria. The acetaldehyde level was higher in yogurts produced with the EPS starter culture YoFlex. The use of mTGase together with an EPS-forming bacteria improved textural, microstructural and organoleptic properties of yogurt produced from goat milk enriched with micellar casein powder.