Effects of enzymatic treatment conditions on dietary fibre content of wheat bran and use of cellulase‐treated bran in cookie

Summary A commercial cellulase preparation (Viscozyme Cassava C) was employed to process wheat bran to improve the ratio of insoluble to soluble dietary fibre. The effects of initial moisture content, enzyme dosage, and incubation time on the content of soluble and insoluble fibre during the enzymatic treatment were investigated. The appropriate conditions for the cellulase treatment were initial moisture content of 0.75 g water g −1 dry matter, enzyme dosage of 9 U g −1 dry matter and incubation time of 120 min under which the ratio of insoluble to soluble fibre of wheat bran was lowered by 42%. Untreated and cellulase‐treated wheat bran was incorporated into cookies at levels of 0%, 20%, 30%, 40% and 50%. Cookie with 50% cellulase‐treated bran showed 21% lower ratio of insoluble to soluble fibre as well as 14% lower hardness and 13% higher overall acceptability than sample with the same amount of untreated bran.