Effects of the interaction of different particle size wheat bran dietary fiber with gluten protein and starch on dough structure and properties.

In this study, WBDF with different particle sizes were used to characterize their structure and physicochemical properties, and their effects on macro-rheology and microstructure of dough were investigated. The results showed that ultrafine comminution disrupted the network structure of WBDF, leading to the decrease of relative crystallinity (from 41.88 to 25.30 and 24.68 %, respectively), weight-average molecular weight (from 216.04 to 211.80 and 193.36 KDa, respectively) and water holding capacity (from 6.53 to 6.20 and 5.32 g/g, respectively). The dough experimental data revealed that the interaction between WBDF and starch effectively inhibited the pasting and aging of starch. In addition, the low rigidity, competitive hydration and mechanical shear of WBDF with small particle size improved the textural properties of dough compared to WBDF with large particle size. However, the steric hindrance effect of WBDF with small particle size inhibited the formation of gluten network at 3 %, 6 % and 9 % addition, resulting in the lowest G' and G" and the highest maximum creep strain of dough. While at further increased (12 % and 15 %), the non-covalent binding between WBDF with small particle size and gluten protein promoted continuous gluten network, which helps to mitigate the adverse effects of dough at low addition levels.