挤压豆渣中可溶性膳食纤维制备工艺的优化

Optimization of technology for preparing soluble dietary fiber from extruded soybean residue

为了获得碱法制备挤压豆渣中可溶性膳食纤维的最适工艺参数,以液固比、温度、时间和碱浓度为试验因子,以可溶性膳食纤维产率为响应值,采用中心旋转组合试验设计进行试验。结果表明:4个因素对可溶性膳食纤维产率的影响大小依次为碱浓度>液固比>温度>时间。通过典型性分析得出可溶性膳食纤维最适制备条件为:液固比26∶1、温度89℃、时间68min、碱浓度1.12%。在此条件下,可溶性膳食纤维产率的预测值为33.96%,验证试验所得可溶性膳食纤维产率为34.12%。回归方程的预测值和试验值差异不显著,所得回归模型拟合情况良好,达到设计要求。在本试验优化的条件下,以经挤压豆渣为原料制备的可溶性膳食纤维产率(34.12%)显著高于以未经挤压豆渣为原料的产率(13.51%)。

Optimized technology for preparing soluble dietary fiber from extruded soybean residue was studied by the central composite rotatable design with four variables of the ratio of liquid to solid, temperature, time and alkali concentration. The yield of soluble dietary fiber was the evaluation index. The results indicated that the effect order of four factors on the yield of soluble dietary fiber was as follows： alkali concentration, ratio of liquid to solid, temperature and time. The canonical analysis revealed that the optimal conditions for preparation of soluble dietary fiber were： ratio of liquid to solid 26 ： 1, temperature 89℃, time 68 min and alkali concentration 1.12%. Under optimal conditions, the predicted yield of soluble dietary fiber from extruded soybean residue was 33.96%, whereas, the experimental yield of soluble dietary fiber was 34.12%. The RSM-predicted yield and the experimental yield of soluble dietary fiber were hot significantly different from each other. The results showed that the empirical model developed by response surface methodology was adequate to describe the relationships between the factors and response values. Under optimal conditions, the yield of soluble dietary fiber from extruded soybean residue （34.12%） was significantly more than that from soybean residue （13.51%）.