Enzymatic Modification of Potato Residue Fiber Improves Cholesterol and Sugar Absorption

Potato residue is rich in dietary fiber (DF) but low in soluble dietary fiber (SDF), and modification is required to generate high-quality DF. In this study, enzymatic modification was performed to produce high-quality DF. The composition, structure, and absorption characteristics of original potato residue dietary fiber (O-DF) was compared with potato residue DF modified using cellulase (C-DF), xylanase (X-DF), and cellulose-xylan complex enzyme (D-DF). The results showed that all products contained five monosaccharides, but the contents of each monosaccharide differed significantly (p < 0.05). Compared with O-DF, levels of cellulose and hemicellulose in C-DF, X-DF, and D-DF were reduced. The network structure of C-DF, X-DF, and D-DF was damaged, and these changes were most significant for D-DF. At pH 7, the cholesterol adsorption capacity of C-DF, X-DF, and D-DF was higher than that of O-DF. DF glucose absorption capacity in 50, 100, and 200 mmol/L glucose solution was ordered D-DF > X-DF > C-DF > O-DF. In conclusion, enzymatic modification with cellulase, xylanase, and cellulase–xylanase can improve SDF content in potato residue, providing a theoretical basis for the future application of modified potato residue DF in the food industry.