Start Publications Heat mediated physicochemical and structural changes of wheat ...
QSense

Heat mediated physicochemical and structural changes of wheat gluten in the presence of salt and alkali

Year: 2021

Journal: Food Hydrocolloids, Volume 120, NOV

Authors: Han, Chuanwu; Ma, Meng; Yang, Tianbao; Li, Man; Sun, Qingjie

Organizations: National Natural Science Foundation of China [32072135]; Young Elite Scientists Sponsorship Program by CAST [2019QNRC001]; Program for Youth Science Innovation in Colleges and Universities of Shandong Province [2020KJF005]; Special Funds for Taishan Scholar Projects of Shandong Province [Ts201712058]

Keywords: Heating; Gluten; Molecular chain; Aggregation; QCM-D adsorption

To understand the heat mediated cross-linking mechanism of gluten in the presence of salt and alkali, the effects of heating on the physicochemical and structural changes of gluten protein was comparatively investigated in this study. Our results showed that the G' value of gluten was mediated by heating, while alkali delayed the transition temperature by approximately 20 degrees C. Salt increased the extensibility of gluten. However, alkali improved gluten strength and toughness. Fluorescence spectroscopy, surface hydrophobicity, and AFM images demonstrated that hydrophobic interactions and aggregations of protein molecular chains were enhanced by both salt and alkali, and heating further promoted these interactions. In addition, alkali reduced the aggregation temperature of large glutenin polymers from 95 to 75 degrees C according to SE-HPLC profiles. RP-HPLC patterns confirmed that alpha- and gamma-gliadin subunits were more susceptible to heat and polymerized after heating at 95 degrees C with alkali. QCM-D results showed that alkali promoted protein-protein interactions in gluten, which was positively correlated with temperature. This study consummates the understanding of heating mediated crosslinking mechanisms of gluten with salt and alkali and provides a more comprehensive theoretical basis for the control of gluten properties and quality of wheat products.