Preparation Soy Isoflavone-glycosidase With Fermentation

Soy isoflavone has a lot of nutriments and health protection effects, so was widely used. As the main active component of soybean, soy isoflavone has been paid more and more attention and known for its medicative health protection function and clinic cure effect.Throught the experiment the Lactobacillus which has the best hydrolysis function for soy isoflavone was selected, conducted to optimize the process conditions of hydrolysis and extraction, and one kind of fermentation soymilk which was riched in genistein and daidzein was prepared. At present there were many ways to hydrolysis soy isoflavones glycoside into soy isoflavones aglycon, that is acid-hydrolysis, alkali-hydrolysis, enzyme-hydrolysis, Smith-hydrolysis, microbe-hydrolysis, but the best way was micro-hydrolysis from security of food.In the process of preparation daidzein and genistein, taking concentration of daidzein and genistein in fermentation soymilk as index the effect of factors on cultivation process had been studied. It was decided through the research that the effect of factors of fermention temperatrue, fermention time and inoculum size on the process of preparation daidzein and genistein. The optimal operation parameters of preparation process were chosen from rotatable design. The optimum hydrolytic parameters for soy isoflavone are gotten, the conclusions are that fermatation temperature 41℃,fermatation time 28h and inoculum size of Lactobacillus 4%. In this condition, concentration of daidzein and genistein are 127.43μg·mL-1.It was decided through the research to the effect of factors of ethanol concentration,extraction temperature and extraction time in the process of extraction daidzein and genistein. Taking concentration of daidzein and genistein in hydrolyzate as index, the optimal operation parameters of preparation process were chosen from design. By orthogonal experiments determine the following optimum extraction conditions: ethanol concentration 90%, extraction temperature 60℃and extracted for 45minutes. In this condition, concentration of daidzein and genistein are 134.41μg·mL-1.In the process of preparation one kind of fermentation soymilk which was riched in genistein and daidzein, the influence of three different proportions sucrose, lactose and glucose was researched by sensory evaluation.The optimum adding amount of surose and lactose are 8% and 2%.