发芽对大豆蛋白凝胶性质的影响

研究了发芽大豆蛋白质凝胶性质的变化。采用碱提酸沉法制备大豆分离蛋白(SPI),以葡萄糖酸-δ-内酯(GDL)为凝固剂制备大豆蛋白凝胶,系统研究了不同芽长大豆蛋白凝胶强度的变化。通过SDS-聚丙烯酰胺凝胶电泳(SDS-PAGE)图谱分析了发芽过程中SPI的变化及其对大豆凝胶强度的影响。结果发现:SPI中7S球蛋白的α'、α亚基和11S球蛋白的酸性亚基A3、A发芽时发生明显降解,但11S球蛋白各亚基在发芽初期变化小,利于大豆蛋白质分子之间形成网络结构使凝胶强度增强。随着发芽时间的延长,11S球蛋白也部分发生降解,凝胶强度下降。

Effect of Germination on Properties of Soybean Gel

The impact of germination on gel property of soybean protein was investigated in the paper.Soybean protein isolate(SPI) were obtained from germinated soybean using alkaline extraction and acid precipitation method.After prepared by adding GDL as coagulant,soy protein gels were analyzed by Texture Analyzer.The influence of SPI changes on strength of soybean protein gel was discussed by SDS-PAGE mapping.The results showed that α'-7S,α-7S,A3-11S and A-11S subunits were easily hydrolyzed by intra-proteases.However,all subunits of 11S globulin had less change than 7S globulin during soybean germination.At the early germination,network structure of soybean gel was easily to form among proteins and the gel strength increased,and then the gel strength decreased due to hydrolysis of 11S globulin.