猕猴桃可溶性膳食纤维酶法制备工艺及抗氧化活性研究
Study on preparation of soluble dietary fiber by enzymatic method from kiwifruit and its antioxidant activity
-
摘要: 以猕猴桃皮渣为原料,采用酶法制备猕猴桃可溶性膳食纤维。在单因素实验的基础上,以纤维素酶添加量、酶解时间、酶解温度和液料比为实验因素,以可溶性膳食纤维提取率为响应值,采用四因素五水平的响应面分析法进行实验,优化提取工艺参数。同时,考察了猕猴桃可溶性膳食纤维对DPPH和ABTS+自由基的清除效果及其还原能力。结果表明,酶法制备猕猴桃可溶性膳食纤维的最佳工艺条件为:酶添加量0.86%、酶解时间2.5h、酶解温度62℃和液料比27∶1(mL/g),在该条件下猕猴桃可溶性膳食纤维提取率预测值为13.379%,验证值为12.983%,响应面法对猕猴桃可溶性膳食纤维提取条件的优化是可行的,可用于实际预测。抗氧化活性实验表明猕猴桃可溶性膳食纤维具有较强的自由基清除效果和还原能力,对DPPH和ABTS+自由基的EC50分别为4.68mg/mL和1.28mg/mL。Abstract: The enzymatic method was adopted to extract soluble dietary fiber from the skin residue of kiwifruit.On the basis of one factor test, the method of response surface analysis with 4 factors including the amount of cellulose, extract time, extract temperature and liquid-to-solid ratio on the extraction ratio of soluble dietary fiber was adopted. Meanwhile, the antioxidant activity of the soluble dietary fiber was tested. The result showed that, these optimal extraction conditions were as follows :the amount of cellulose 0.86%, extract time 2.5h, extract temperature 62℃ and the liquid-to-solid ratio 27∶1mL/g, the predicted value and measured value of the soluble dietary fiber were 13.379% and 12.983%, respectively. Results indicated that the obtained mode developed by response surface methodology was feasible for practical prediction. The antioxidant activity test showed that, the soluble dietary fiber from kiwifruit had strong radical scavenging activity and reducing capacity, the EC50 of DPPH and ABTS were 4.68mg/mL and 1.28mg/mL, respectively.