Staling and water dynamics in high-gluten bread

Staling indicators (texture, amylopectin retrogradation, water status and proton molecular mobility) in a high-gluten bread (25% flour substitution and water absorption at 500 Brabender Unit) were compared to a control during 1 week of storage. The contribution of macroscopic crumb to crust water migration on frozen water, molecular mobility and retrograded amylopectin was evaluated in bread loaves and bread crumb stored in NMR tubes. High-gluten bread was softer and had increased volume, cohesiveness, springiness, moisture and frozen water contents than the control, with comparable amylopectin retrogradation. An increased proton molecular mobility was observed in fresh high-gluten bread. In condition of no occurrence of macroscopic water migration, proton molecular mobility indicated reduced changes in breads during storage, suggesting the important role played by migration in the staling process. These changes were further reduced in the high-gluten bread, indicating an influence of the larger moisture content but also a contribution of gluten in regulating molecular changes.