Optimization of Extraction Process of Soluble and Insoluble Dietary Fiber from Abelmoschus Esculentus

In order to optimize the extraction process of dietary fiber from Abelmoschus esculentus, by using Abelmoschus esculentus as the raw material, the soluble dietary fiber was extracted from Abelmoschus esculentus by acid hydrolysis method and the insoluble dietary fiber was extracted from Abelmoschus esculentus by enzymatic hydrolysis method. The optimum technological conditions of the soluble and insoluble dietary fiber in Abelmoschus esculentus were determined by using the single factor experiment and orthogonal experiment. The results showed that the ratio of solid to liquid was the most important factor affecting the yield of soluble dietary fiber extracted from Abelmoschus esculentus by acid hydrolysis method, followed by the value of pH, extraction time and extraction temperature. The optimal extraction conditions were as follows:the solid-liquid ratio 1:30(g/mL), pH 7.0, extraction temperature 100℃, and extraction time 100 min. And the yield of soluble dietary fiber from Abelmoschus esculentus could reach 13.52% under these conditions. PH and enzymatic hydrolysis temperature were the most influential factors on the yield of insoluble dietary fiber from Abelmoschus esculentus. The optimal extraction conditions were as follows:temperature 60℃, pH 5.0, enzyme dosage 0.7% and enzymatic hydrolysis time 60 min. And the yield could reach 37.82% under these conditions. By using the optimized conditions, the yield of soluble dietary fiber in the six varieties of Abelmoschus esculentus were measured to be above 13%, while the average yield of insoluble dietary fiber was measured to be 36.15%. The extraction yield of dietary fiber from Abelmoschus esculentus under the optimized conditions was higher, which could provide reference for the extraction of dietary fiber from Abelmoschus esculentus.