转谷氨酰胺酶改性大豆分离蛋白条件研究

摘要

利用微生物转谷氨酰胺酶（MTGase）对大豆分离蛋白（SPI）进行改性，探讨pH、反应温度、反应时间、底物浓度、酶/蛋白质比对SPI改性影响，采用正交试验优化改性条件。结果显示，酶/蛋白质比和底物浓度对SPI改性影响较小；pH、温度和时间对该改性作用影响较大，该3种因素对SPI改性影响大小依次为pH、温度和时间；MTGase改性SPI的最佳条件为pH 5.5、温度55℃、时间30 min、底物浓度2.0%、酶/蛋白质比10 U/g。%The effects of pH,reaction temperature,reaction time,substrate concentration and the ratio of enzyme to protein on the modification of soy protein isolate(SPI)by transglutaminase were investigated. The results showed that pH,reaction time and temperature had greater influences on the modification in the predominant order of pH,reaction temperature and reaction time. An optimum condition was obtained by orthogonal experiment,that is,pH 5.5,reaction temperature of 55℃, reaction time of 30 min,a substrate concentration of 2.0%,and a ratio of enzyme to protein of 10 U/g.