不同物理法提取高温大豆粕中蛋白的比较研究

比较了加热、均质、超声和微波4种物理手段对提取高温大豆粕中大豆蛋白的辅助作用,并对不同方法提取的蛋白进行了聚丙烯酰胺凝胶电泳(SDS-PAGE)、粒度分布、相对分子质量分布及热性质分析.研究发现120 ℃(0.1 MPa,20 min)热处理对大豆蛋白的提取效果最好,蛋白浸出率可达65.58%.SDS-PAGE、凝胶渗透色谱(GPC)和粒度分布结果显示,加热、超声和微波处理所得蛋白提取物为高相对分子质量聚集体,但除微波处理外,其分子粒径也有所减小;均质可使蛋白提取物的相对分子质量、粒径减小.差示量热扫描(DSC)结果表明,均质处理所得提取物尚有吸热峰存在,而其他手段处理所得提取物已完全变性.

Comparison of different physical methods on extracting protein from high temperature soy meal

Four physical methods(heat treatment,homogenizing,ultrasonic treatment,microwave treatment) were compared on extracting protein from high temperature denatured soy meal. The protein extracts were analyzed by SDS-PAGE, size distribution, gel permeation chromatography(GPC), differential scanning calorimetry(DSC).The results showed that heating for 20 min at 121 ℃(0.1 MPa) was the best extracting method,which gave a 65.58% extracting rate of soy protein. According to SDS-PAGE and GPC analysis,protein extracts obtained by heat treatment,ultrasonic treatment and microwave treatment had larger relative molecular weight,while homogenizing treatment decreased its relative molecular weight.According to size analysis,the molecular size of protein extracts decreased except the extract obtained by microwave treatment.The results of DSC showed that there was still endothermic peak for the protein extract obtained by homogenizing treatment,while protein extracts obtained by other treatments were completely denatured.