Optimization of the extraction of water insoluble dietary fiber from rapeseed hull

Water insoluble dietary fiber extracted from rapeseed hull by alkaline hydrolysis method and by using Sodium hydroxide(NaOH) as solution was studied.Effects of four crucial parameters(the ratio of material to solution,alkali concentration,temperature and time) on extraction yield of water insoluble dietary fiber were investigated trough single-factor experiment method.Subsequently,a central composition experimental design was performed to attain the maximum extraction yield of water insoluble dietary fiber.Under the optimized conditions as follows:the ratio of material to solution 1:17(g/mL),alkali concentration 2.0mol/L,temperature 50℃ and time 45min,the yield of water insoluble dietary fiber was found to be 65.92%.