响应面法优化苦荞酒糟黄酮提取工艺的研究

苦荞酒糟是苦荞酒加工的副产物,苦荞酒糟中含有丰富的黄酮组分,采用食用乙醇提取酒糟黄酮还原到苦荞蒸馏酒中,是一种资源合理利用方法.为确定采用乙醇回流法提取苦荞酒糟中黄酮类成分的最佳工艺条件,以黄酮得率为指标,采用响应面法对主要工艺参数进行优化并得到回归模型.方差分析结果表明:回归模型较好地反映了苦荞酒糟黄酮得率与乙醇体积分数、提取时间和液固比的关系；最优工艺条件为乙醇体积份数为70％vol,提取时间3.3h,液固比为24∶1 (mL∶g).此工艺条件下提取酒糟黄酮得率为1.642g/100g,回收率为93.3％,回归模型的预测值与实际值之间具有较好的拟和度.

Extraction of total flavonoids from tartary buckwheat stillage by response surface methodology

Grain stillage,by-products of tartary buckwheat alcohol processing has rich tartaiy buckwheat total flavonoids.Extracting total flavonoids from grain stillage and adding it back to tartary buckwheat alcohol was a reasonable approach of resource utilization.With the aim of optimization of flavonoids extracting process from the tartary buckwheat grain stillage by the alcohol refluxing method,a Box-Behnken experiment design and the response surface methodology was used to investigate the influence of four main process parameters including concentration of ethanol,extraction time,and ratio of solvent to raw material on the yield of flavonoid and establish a regression model.Variance analysis showed that the regression model fit the relationship of flavonoid yield to the three process parameters well.The obtained optimum extraction parameters weretime 3.3h,concentration of ethanol 70％vol,and ratio of solvent to raw material 24∶1 (ml∶g).The flavonoid yield and recovery rate with the optimized procedure was 1.642g/100g and 93.3％,respectively.The experimental values agree with those predicted from the regression model indicated a good fitness.