Effect of high-molecular weight dextran-enriched sourdough fermented using Leuconostoc mesenteroides ATCC 8293 on bread quality and gluten

Abstract

This study aimed to prepare high-molecular-weight (HMw) dextran-enriched sourdough (HMw-DT-SD) using Leuconostoc mesenteroides ATCC 8293 and to evaluate its effect on the quality of bread. The results demonstrated that HMw-DT-SD improved the bread quality by increasing the bread volume from 3.86 cm3/g to 5.04 cm3/g; the bread staling rate decreased by 49.02% compared with that in control. The relationship between bread quality and dough gluten was further investigated. The acidity during bread making greatly influenced the effect of dextran on gluten. The HMw-DT-SD hindered the gluten depolymerization under acidic conditions (pH = 3.6) and had a low free thiol content. In addition, the lower content of antiparallel β-sheets in the bread dough might contribute to the depolymerization of macromolecular gluten (pH > 4.4), thus improving the bread volume and texture. The HMw-DT-SD increased the content of β-turn structures in bread, suggesting gluten of lower resistance to extension.