Insights into heat-induced molecular-level interactions between wheat and common buckwheat proteins

Abstract

This study investigated the heat-induced interactions between wheat and buckwheat proteins by heating wheat proteins, buckwheat albumin, globulin, and mixtures of wheat flour with buckwheat albumin/globulin at 50, 65, 80, 95, and 100 °C. The results showed that the cross-linking reactions of wheat glutenin with buckwheat albumin and globulin initiated at 80 and 95 °C, respectively. Buckwheat albumin decreased the extractability of α-gliadin by 35 % at 95 °C and 5.9 % at 100 °C. The linkage of buckwheat globulin to wheat glutelin prevented part of the wheat gliadin from linking to glutelin, resulting in the extractability of α- and γ-gliadin increased by 8.6 % and 11 % at 95 °C, respectively. The chemical forces results indicated that interactions between wheat and buckwheat proteins were primarily driven by disulfide bonds and hydrophobic interactions. This study provides a theoretical basis for better regulating the wheat-buckwheat protein network to improve the quality of buckwheat-enriched products.

Keywords: Albumin; Cross-linking; Fagopyrum esculentum; Globulin; Heat treatment.