Semi-solid state fermentation and enzymatic hydrolysis impeded the destroy of wheat bran on gluten polymerization

In order to reduce destroy of wheat bran on gluten network, wheat bran was pre-treated by co-fermentation with yeast and lactic acid bacteria or (and) xylanase hydrolysis. Effects of bioprocessing treatment on the nutritional value of wheat bran, thermomechanical properties of dough and thiol disulfide bonds contents, secondary structures, thermal stability, and microstructures of gluten protein were investigated. The results showed that fermentation and enzymatic hydrolysis increased polyphenolic compounds and soluble arabinoxylan contents in wheat bran, and the ratio of soluble dietary fiber (SDF)/insoluble dietary fiber (IDF) in the enzymatic hydrolysis and fermentation bran group (E + F) also increased about 8.1% compared with the original wheat bran group. The modified wheat bran significantly (P < 0.05) increased the disulfide bonds contents (5.8%-13.9%) of gluten protein compared with the original wheat bran. The bioprocessing treatment effectively reduced the damage of wheat bran to the gluten network, which might be due to the increase of the SDF/IDF ratio. Among all the wheat bran groups, the E + F group had the highest β-sheet and α-helix contents. However, the thermal stability of gluten protein was not significantly (P > 0.05) improved. Results have shown that bioprocessing treatment could impede the damage of wheat bran to dough and gluten polymerization.