Process Optimization and Functional Study of Enzymatic Preparation of Corn Husk Dietary Fiber

In this study, corn husk, a by-product formed during corn processing, was used as raw material, and a combination of enzymes was used to prepare corn husk dietary fiber. Single factor experiments and response surface optimization were used to determine the optimal process parameters and study its functionality. The results showed that the addition of alkaline protease was 0.742%, pH was 10, temperature was 54 ℃, and enzymatic hydrolysis was 4 h. Starch complex enzymatic hydrolysis conditions was as follows: The addtion of starch complex enzyme (amylase:saccharification enzyme=1:1 (m/m)) was 0.727%, pH was 6.76, temperature was 65 ℃, and enzymatic hydrolysis was 2 h. Under the optimal conditions, the dietary fiber content of corn husk reached the highest (86.65%±0.72%). Its water holding capacity was 3.93±0.17 g/g, and its swelling property was 3.70±0.20 mL/g. The oil holding capacity for soybean oil, corn oil, rapeseed oil and lard oil were 1.80±0.04, 2.59±0.01, 2.53±0.06, 3.47±0.19 g/g, respectively. Cholesterol adsorption in gastric environment and intestinal environment were 0.63±0.03 mg/g and 0.31±0.02 mg/g, respectively. The corn husk dietary fiber had good adsorption to different concentrations of glucose solution, and had a strong ability to inhibit fat digestion in vitro.