Optimization of Ultrasonic Assisted Enzymatic Extraction Process and Analysis of Physicochemical Properties of Dietary Fiber from Camellia oleifera Meal

Dietary fiber has many physiological functions and outstanding application prospects, while the physiological characteristics of soluble dietary fiber are better than that of insoluble dietary fiber. In order to improve the camellia meal in DF SDF yield, SDF yield as evaluation index, the ultrasonic assisted enzymatic, through the single factor experiments of enzyme, ultrasonic time, ultrasonic power, material liquid than four factors were studied, and based on single factor experiments, response surface optimization experiment, and the DF of get the physical and chemical properties and structure analysis. The results showed that the optimal extraction conditions were as follows: Enzyme dosage 0.2%, ultrasonic time 31 min, ultrasonic power 210 W, solid-liquid ratio 1:23 g/mL, SDF yield was 12.43%, IDF yield was 68.39%. The total dietary fibre (TDF) holding capacity, oil holding capacity and swelling capacity were 4.36 g/g, 3.67 g/g and 6.83 mL/g, respectively. The adsorption rate of cholesterol was 5.79 mg/g at pH2 and 8.38 mg/g at pH7. The adsorption rate of glucose was 11.49 mg/g. Through the analysis of structure characterization, it was speculated that the TDF of Camellia oleifera meal contains lignin, cellulose, hemicellulose and sugars. The surface of TDF was porous and uneven, and the particle size was 50.699 nm. This study improved the yield of SDF and proved that TDF of Camellia oleifera meal had good physical and chemical properties and structure, which would provide reference for improving the added value of Camellia oleifera meal.