Osborne分级法提取藜麦糠清蛋白及功能性质研究

以藜麦糠为研究对象,采取超声辅助Osborne分级法对藜麦糠中清蛋白进行提取。在单因素实验基础上,应用Box-Behnken方法选取料液比、提取温度、提取时间3个因素,以清蛋白提取率为响应值进行优化,确定藜麦糠清蛋白的最优提取条件为:料液比1∶37（g/m L）、提取温度46℃、提取时间25 min,在此条件下藜麦糠清蛋白提取率为43.21%,与理论预测值43.76%相比,其相对误差约为1.25%。说明通过响应面分析优化后得到的回归方程在实践指导方面具有一定的意义。对藜麦糠清蛋白功能（溶解性、持水力、乳化性、起泡性）特性进行了测定,结果表明p H为2.5即等电点时,清蛋白的溶解度最低,持水力最小达到1.33 g/g,乳化性最低,乳化稳定性反而最好,而起泡性和起泡稳定性在等电点附近均最差。 

Extract of albumin from quinoa chaff by Osborne classification method and functional properties

Quinoa chaff is the research object, albumin from quinoa chaff was extracted by using ultrasonic auxiliary Osborne classification method.Three extraction parameters including solid-liquid ratio, extraction temperature and extraction time were optimized using Box-Behnken method and response surface methodology with protein extraction ratio as the response value.The research was based on single factor experiments for achieving maximum the protein extraction ratio. The optimal extraction conditions were determined as a solid/liquid ratio of 1∶37 (g/m L) , an extraction temperature of 46 ℃, and an extraction time of 25 min. Under these optimized conditions, quinoa chaff albumin extraction yield was 43.21%, compared to the theoretical value 43.76%, the relative error of 1.25%. Optimized by response surface regression equation derived some practical significance.Experiment of quinoa chaff albumin functional properties (solubility and hold water, emulsification, foaming) were determined.The results showed that pH2.5 isoelectric point, namely the solubility of albumin was the lowest, a hold water minimum was 1.33 g/g, emulsification was lowest, but emulsifying stability was best, and the foaming ability and foam stability in isoelectric point nearby were worst.