Effect of microbial transglutaminase on gel property of soybean protein isolates

Soybean protein isolate (SPI) was modified by transglutaminase(MTGase)and the gel property of SPI was investigated. It showed that the gel property of SPI was greatly influenced with the addition of MTGase, and the change of pH, temperature, concentration of SPI and the reaction time. The best gel property of the modified SPI emerged under enzyme dosage 5 U/g,pH 8.0,37℃, and the protein concentration 12%. At the same time, the gel strength was increased as the time was prolonged. In addition, the network of the protein molecules was formed by the polymeric reaction of SPI catalyzed by MTGase.