By-products of food processing are underutilized. For wheat bran a simple, efficient extraction method with two industrial enzymes is described, which can be integrated into the production sites of nutrient additives, enzymes and natural products.

Abstract

Wheat bran is an abundant source of starch fragments, peptides and amino acids which represent a valuable nutrient source for bacterial production of natural products. The commercial protease Corolase® 7089 efficiently improves extraction of N-compounds from wheat bran. Here we show the effect of combined applications with the commercial α-amylase Termamyl® 120. Wheat bran was extracted with at a liquid/solid ratio of 12.3. The same product yield of 24% was obtained after simultaneous enzyme application for 1 h and after serial application (first amylase) with a total treatment time of 7.75 h. Crude protein concentration in the product was 23% and 22%, respectively. Measurements of the sugar concentration in the extraction liquid indicate that the degree of starch hydrolysis was decreased in the presence of protease. In a stirred pilot-scale reactor a product yield of 32% was achieved.