微射流和超声波对长期贮藏大豆分离蛋白溶解性的影响

Effect of microfluidization and ultrasonic on solubility of soybean protein isolate

摘要: 在常温贮藏条件下,大豆分离蛋白(SPI)的溶解性随贮藏时间的延长而逐渐下降。通过测量贮藏时间0、120、240、360d的SPI,结果显示可溶性蛋白含量从贮藏0d的59.5%±1.2%降低到360d的43.3%±1.6%。粒径和浊度分析显示随贮藏时间的延长,SPI发生聚集,不利于溶解的变化。而经过微射流和超声波的双重处理后,SPI溶液中可溶性蛋白含量上升到88.1%±1.3%。SPI凝胶电泳图谱和凝胶排阻色谱显示蛋白亚基的变化有利于提高溶解性。SPI聚集的粒径减小,分布范围变窄。SPI在不同悬浮液的浊度都明显下降。

Abstract: The solubility of soybean protein isolate ( SPI) decreased gradually with extension of storage time at room temperature.The content of soluble protein reduced from 59.5% ± 1.2% to 43.3% ± 1.6% , when the storage time up to 360d.Size and turbidity of SPI showed that aggregation didn’t stead to the dissolution with extension of storage time.The proportion of soluble SPI increased 88.1% ± 1.3% by used microfluidization and ultrasonic. In addition, SDS-PAGE and SEC-HPLC showed that the changes of subunits conducive to improve solubility of SPI after microfluidization and ultrasonic treatment. Distribution of SPI aggregation size became small and narrower after microfluidization and ultrasonic treatment.Turbidity of different supernatants all decreased sharply.