Abstract: Dietary fibre was extracted from wheat bran in order to hydrolyze starch and protein using α-amylase and alkaline protease,respectively. By orthogonal tests,the optimal enzymatic reaction conditions for α-amylase are as following:α-amylase addition 3%([E]/[S]) ,90 ℃,and hydrolysis time 2 h. Alkaline protease was selected as the optimal commerical protease to hydrolyze the wheat bran protein. The optimal reaction conditions of alkaline protease are as following enzyme addition 1.4%([E]/[S]) ,60 ℃ and hydrolysis time 1.5 h. The extraction rate of dietary fibre from wheat bran reaches 77.6% under the above optimal enzymatic conditions.

Key words: wheat bran； dietary fibre； &alpha, -amylase； alkaline protease