鲜米糠中蛋白质的提取工艺研究

Extraction Technology of Fresh Rice Bran Protein

以新鲜米糠为原料,采用碱法、酸法、盐法分步对米糠蛋白进行复合提取。在提取过程中,以蛋白质提取率为指标,确定料液比、pH值、温度、时间对米糠蛋白提取率的影响,通过正交试验确定这3种方法各自提取蛋白的最佳工艺,最后依次采用碱提、酸提、盐提的最佳工艺条件分步对米糠蛋白进行提取。结果表明,碱法提取新鲜米糠蛋白最佳工艺条件:时间2.5 h,pH值12,温度30℃,料液比1∶11,提取率为34.49%;酸法提取新鲜米糠最佳工艺条件:时间3 h,pH值0.05,温度35℃,料液比1∶11,提取率为25.88%;盐法提取新鲜米糠蛋白最佳工艺条件:NaCl浓度0.6 mol/L,温度35℃,料液比1∶11,提取率为15.66%。复合法提取新鲜米糠蛋白总提取率达60.12%。

Fresh rice bran is selectd to extract rice bran protein by alkali method,acid method and salt method.The yield of ptotein in fresh rice bran is taken a key index to determine the effects of material-liquid ratio,pH values,extraction time, temperature and salt concentration on the extraction of protein.The optimal extraction processing parameters of three methods of three kinds of bran are explored by orthogonal experiments.The extraction processing is orderly alkali method,acid method and salt hydrolysis method.Results indicate that the optimal extraction processing parameters of alkali extraction method for the rice bran are 2.5 h,pH 11,45 ℃ and material-liquid ratio of 1 ∶11,the extraction rate is 34.49%;The optimal extraction processing parameters of acid method for the rice bran are 3 h,pH 0.05,35 ℃ and material-liquid ratio of 1∶11,the yield is 25.88%;The optimal extraction processing parameters of salt method are 0.6 mol/L NaCl,35 ℃ and material-liquid ratio of 1∶11,the extraction rate is 15.66%.The total yield reached 60.12% by three methods extraction.