A comparative study of molecular structure, rheology, and thermal characteristics of deacetylated konjac glucomannan-treated gluten during frozen storage

Konjac glucomannan is extensively employed to enhance the quality of wheat-based products. Despite this, the utilization of natural KGM in the food industry is restricted due to its inadequate mechanical attributes, heightened susceptibility to humidity, and unappealing taste profile. In this study, the influence of deacetylated konjac glucomannan (DKGM) on the structure, rheology, and thermal characteristics of gluten during frozen storage was explored. Furthermore, the mechanism outlining the action between gluten and DKGM was analyzed. The secondary structure results showed that DKGM promoted the formation of alpha-helices and beta-sheets in gluten. Scanning electron microscopy analysis confirmed that DKGM made the gluten network more stable. Moreover, DKGM provided a significant improvement in the rheological and thermal properties of frozen gluten. This is attributes to the fact that DKGM alters the hydrophobic residues in frozen gluten. Overall, this work indicates that the molecular structure and thermal properties of gluten are optimally substantial improvements at a substitution content of 1.5% D3 (deacetylation degree of 95%) in the dough. These findings provide a reference value for the application of DKGM in frozen wheat-based foods.