响应面试验优化亚临界水提取核桃粕蛋白工艺及其氨基酸分析

Optimization of Subcritical Water Extraction of Walnut Meal Protein by Response Surface Methodology and Amino Acid Analysis

本研究以新疆核桃粕为实验原料,利用亚临界水辅助提取核桃粕蛋白,分别以提取时间、料液比、提取温度、p H值为单因素研究对蛋白提取率的影响。通过单因素试验确定合适的因素水平,以响应面优化分析得到核桃粕蛋白提取的最佳条件。结果表明:核桃粕的最佳提取工艺为p H 9.0、料液比1∶25(g/m L)、提取温度133℃,此条件下的蛋白提取率可达到75.01%。氨基酸的结果分析表明:氨基酸种类齐全,谷氨酸、精氨酸、天冬氨酸3种含量最高,共占氨基酸总量的59.7%,必需氨基酸占20.03%。亚临界水提取蛋白的提取率较高,操作方便,适用于核桃粕蛋白提取。

The subcritical water extraction of walnut meal protein was optimized by response surface methodology.The variables optimized were extraction time,solid-to-solvent ratio,extraction temperature and pH.The response was the extraction yield of protein.One-factor-at-a-time method was used to determine the appropriate levels of independent variables for further optimization by response surface methodology.The results showed that the optimal conditions were as follows:pH,9.0;solid-to-solvent ratio,1:25(g/mL);and temperature,133℃.Under these conditions,the extraction yield was up to75.01%.The results of amino acid analysis indicated that the walnut protein contained almost all kinds of amino acids with glutamic acid,arginine,and aspartate being the predominant amino acids,accounting for59.7%of the total amino acids.Essential amino acids accounted for20.03%.Sub critical water extraction could be considered as convenient and efficient method for the extraction of walnut protein.