Phenolic compounds and free sulfhydryl groups in whole grain wheat flour modified by xylanase

Knowledge of the structural behavior of dough elaborated using whole grain wheat flour (WGWF) and xylanase is fundamental for the elaboration of products with high nutritional content, especially when the particle size of the flour is altered. In the present study, we investigated the effect of varying concentrations of xylanase on the formation of dough with different particle sizes of WGWF.

Phenolic compounds, fibers and proteins are the components that undergo the most change and interfere with dough formation. A small particle size favors the extraction of phenolic compounds and dietary fibers, resulting in a high-quality dough. There was a protective effect of the stable phenolic compounds on the gluten network. An increase in fiber degradation and a decrease in phenolic compounds was noted as the xylanase concentration increased. Although xylanase increased free sulfhydryl (-SH) groups in gluten, there was no change in dough formation and dough stability with an increasing xylanase concentration.

The WGWF with a smaller particle size does not contribute to the loss of quality in dough elaboration. The addition of intermediate amounts of xylanase (20 mg kg^-1 ) in samples with a particle size of 158 μm can be used to improve dough characteristics. © 2019 Society of Chemical Industry.