Wheat bran dietary fibre‐induced changes in gluten aggregation and conformation in a dough system

Abstract

This study was conducted to determine the effect of wheat bran dietary fibre (WBDF) on aggregation and conformational changes of gluten in fermented and unfermented dough systems. The results revealed that WBDF has an advantage in maintaining the content of glutenin macropolymer (GMP) in the fermentation process. The analysis of the molecular weight distribution showed decreased content of larger polymeric proteins (LPPs). At the same WBDF level, after fermentation, the content of larger polymeric proteins (SPPs) increased, likely due to the polymerisation of the gliadins. Additionally, fluorescence spectroscopy and surface hydrophobicity analysis revealed that, in fermented dough, with the increase of WBDF content, the protein hydrophobicity significantly increased from 6.56 to 9.43 (P < 0.05). Hydrophobic interactions contributed to the macromolecular unfolding and/or aggregation of gluten. Also, WBDF may induce changes in dough properties by inducing conformational changes in the gluten protein.

Black rice flour‐induced changes in gluten conformation in fresh, pre‐fermented and frozen dough

“…The degree of LPP depolymerization of the TD added with small particle size black rice flour (6.02%) was less than that of the wheat flour system (22.81%), which means that adding small‐particle size black rice flour significantly inhibits the deterioration of gluten. Under the premise that black rice flour disrupts the formation of interchain disulfide bonds, glutenin is more likely to aggregate through non‐covalent interactions (Linlaud et al ., 2011; Ma et al ., 2021). Protein molecular weight distribution is closely related to the rheological properties of dough, the limited reduction of LPP may explain the lower decrease in the rheological properties of the composite flour frozen dough (Feng et al ., 2022).…”

“…The filtrate was separated by liquid chromatography (LC) using an Agilent 1260 Infinity LC system (Agilent Technologies Inc., Santa Clara, CA, USA) equipped with a Biosep SEC‐4000 column (Phenomenex, Torrance, CA, USA). The experimental conditions were as follows: mobile phase A, acetonitrile (containing 1% trifluoroacetic acid); mobile phase B, water (containing 1% trifluoroacetic acid); isocratic elution mode (A:B = 1:1); 0.5 mL/min flow rate; 20 μL injection volume; 30 °C column temperature and ultraviolet (UV) detection at 214 nm (Ma et al ., 2021).…”