Effects of Co-rotating Twin Screw Extrusion Modification on Soluble Dietary Fiber and Nutrients in Rice Bran.

This study aimed to prepare modified rice bran products with high soluble dietary fiber content and good nutrients retention. The rice bran was used as raw material and the soluble dietary fiber content as investigation index. Based on the single factor experiments, the response surface method was applied to optimize the process conditions of rice bran extrusion and expansion. Besides, the physical indices (packing density, color, holding capacity, swelling capacity, water solubility, oil extraction rate, and cation exchange capacity) and nutritional indices (calcium, magnesium, potassium, iron, zinc, phosphorus, VB1, VB2, VE, and niacin contents) of rice bran before and after modification were determined. The results showed that the extrusion optimum technological conditions for soluble dietary fiber from rice bran: double screw speed of 264 r/min, sleeve water content of 26.5%, sleeve inside the fourth district heating temperature of 129 °C, and the optimal yield of modified rice bran soluble dietary fiber was 27.89%. The physical properties of modified rice bran were improved, and all nutritional components except niacin were well retained. The content of soluble dietary fiber in rice bran prepared by this method was successfully increased, and the qualities and nutrients of modified rice bran were better retained, which was suitable for the development of new products and enrichment of food categories. [ABSTRACT FROM AUTHOR]