藜麦蛋白提取工艺优化及其功能特性研究

Optimization of Extraction Process of Quinoa Protein and Its Functional Properties

以预处理后的藜麦粉为原料,采用碱溶酸沉法提取藜麦蛋白。通过单因素试验,结合Box-Behnken试验设计,确定藜麦蛋白的最佳提取条件,并在不同pH值下对藜麦蛋白的功能特性进行研究。结果表明,藜麦蛋白的最佳提取条件为:料液比1∶12.0 (g/mL)、提取时间2.5 h、提取温度46℃、pH值10.5,此条件下的蛋白提取率为(78.86±0.79)%,蛋白纯度为87.58%;同时pH值对藜麦蛋白的功能特性有显著影响,即当pH值接近蛋白等电点时,溶解性、乳化性、持水性等多项功能特性较差;当pH值高于等电点时,随着pH值的增加,藜麦蛋白的各项功能特性均有所提高。

With pretreated quinoa flour as the raw material, the quinoa protein is extracted by alkali dissolving and acid precipitation method. The optimal extraction conditions of quinoa protein are determined through the single factor test combined with Box-Behnken test design, and the functional properties of quinoa protein are studied at different pH values. The results show that the optimal extraction conditions for quinoa protein are as follows: solid-liquid ratio is 1∶12.0(g/mL), extraction time is 2.5 h, extraction temperature is 46 ℃, pH value is 10.5, and the protein extraction rate under such conditions is(78.86±0.79)%, protein purity is 87.58%. At the same time, pH value has a significant effect on the functional properties of quinoa protein. When the pH value is close to the protein isoelectric point, many functional properties such as the solubility, emulsification and water holding capacity are poor;when the pH value is higher than the isoelectric point, with the increase of pH value, various functional properties of quinoa protein are improved.