胡麻籽粕蛋白质提取工艺优化

Optimization of flaxseed meal protein extraction

以脱脂后的胡麻籽粕为原料,加以超声波辅助碱溶酸沉法对胡麻籽粕中的蛋白质进行提取。运用考马斯亮蓝法对提取液中蛋白质含量进行测定,以蛋白质提取率为指标,对超声波功率、时间、料液比、碱提p H值及温度等单因素进行试验,根据单因素试验结果探讨这五种因素对蛋白质提取率的影响。根据spss18.0对试验数据进行处理,选取对蛋白质提取率影响较大的因素进行正交试验,运用正交试验对单因素提取结果进行优化,并对优化结果进行验证。结果表明,胡麻籽粕中蛋白质的最佳提取工艺为:超声波功率550W、时间2h、料液比1∶30、碱提p H 10、温度50℃,经验证试验后得到蛋白质提取率为63.0%。文中还对酸沉工艺进行了研究,结果表明,在p H为4时,蛋白质含量最高,故确定胡麻籽粕蛋白质等电点为4。

Defatted linseed meal with ultrasound - assisted alkali solution and acid were used in linseed meal protein extraction. Coomassie blue method was applied to determine the protein content. Protein extraction rate was the index, the effects of five factors including ultrasonic power, time, solid - hquid ratio, pH of alkali extraction and temperature were investigated on the protein extraction rate according to single factor test results. Then based on spss18.0 test data, factors greatly affected the extraction rate were chosen for orthogonal test. The optimized extraction results from orthogonal experiment showed that the best extraction condition was： ultrasonic power 550W, time 2h, solid - liquid ratio 1 ： 30, alkali extraction pH 10, temperature 50℃. Under the above condition, protein extraction rate was verified as 63.0%. The paper also studied acid precipitation process, the results showed that at pH 4, the protein content was the highest. Therefore, the isoelectric point of linseed meal protein was 4.