青稞蛋白质碱法提取条件的优化研究

Study on condition optimization of extracting proteins from highland barley by alkaline

采用碱提酸沉法制备青稞粗蛋白,以蛋白质提取率为考察指标,采用单因素实验研究了NaOH浓度、料液比、提取温度和时间对青稞蛋白质提取的影响,运用正交实验优化了其碱法提取条件。结果显示,该4种因素对青稞蛋白质提取表现出不同程度的影响,前3种因素对青稞蛋白质提取的影响大小依次为NaOH浓度、料液比和提取温度。在提取时间为1.0h时,青稞蛋白质碱法提取的优化条件为:料液比1∶12g/mL、NaOH浓度为0.15%、提取温度55℃。青稞蛋白质酸沉pH为4.5。按此条件制备青稞粗蛋白,其提取率和蛋白质含量分别达到72.36%和83.35%。

Crude protein from highland barely powder was prepared by the method of alkali extraction and acid precipitation. With the extraction rate of crude protein as an index,the effects of NaOH concentration,materialliquid ratio,extraction temperature and time on the extraction were investigated. The extraction condition was optimized by orthogonal experiment. The results showed that the factors affected the extraction of proteins from highland barley in the predominant order of NaOH concentration ,material-liquid ratio and extraction temperature. When the extraction time was 1.0h,an optimum extraction condition for the crude protein was obtained,that was, NaOH concentration of 0.15%, material-liquid ratio of 1：12g/mL and extraction temperature of 55℃. The precipitation pH value of proteins from highland barely was 4.5. Under the above conditions,the extraction rate of crude protein from highland barely and its protein content was 72.36% and 83.35%,respectively.