Effects of glycation treatment on the structural, physicochemical, and in vitro digestible properties of tartary buckwheat protein

Abstract

Tartary buckwheat protein (TBP) has a balanced amino acid composition and multiple health benefits, but it has not been fully utilized in the food industry because of its insufficient functional characteristics. Glycation is an effective strategy to enhance the function of food-derived proteins. This study was to investigate the effects of glucose and its ratio on the structure, physicochemical properties and in vitro digestibility of TBP during moist heat glycation. The results showed that glycation degree increased with glucose proportions, which facilitated the formation of TBP-glucose conjugates through hydrogen bonding, thus reducing tryptophan exposure. Moreover, glycation led to reduced aggregation between proteins and formation of more amorphous structures due to steric hindrance introduced by glucose. Notably, glycation significantly improved solubility (from 67.20% to 80.01%), foaming capacity (from 20.00% to 26.64%), and emulsifying activity (from 3.49 m2/g to 4.12 m2/g). Conversely, glycation reduced free sulfhydryl groups, surface hydrophobicity, turbidity, as well as gastric and intestinal digestibility of proteins. Considering the functional and digestive properties, the best results were obtained with TBP:glucose = 5:3. This study will help to elucidate the mechanism of TBP modification under glycation conditions and provide a theoretical basis for the development of TBP-related products.