γ-irradiation of wheat flour dough: The influence of starch hierarchical structure and physicochemical properties

Irradiation has been shown to cause a change in physicochemical properties and starch depolymerization of wheat flour. However, the impact of starch hierarchical structure and physicochemical properties on dough's viscoelastic behavior during irradiation treatment remains unexplored. Therefore, this study investigated the effect of γ-irradiation (0, 5, 10, 15, and 20 kGy) on the viscoelastic properties of dough and the hierarchical structure and physicochemical characteristics of starches isolated from irradiated dough. Irradiation weakened the gluten network structure and decreased the starch-gluten interaction. Moreover, irradiation reduced the dough's elasticity, viscosity, deformation-resistant capacity, hardness, springiness, cohesiveness, and resilience. Irradiation treatment disrupted the short-range ordered structure, reduced the crystalline lamellae thickness and crystallinity, and dissociated the double helix structure of starch, thus increasing solubility and decreasing peak, trough, and final viscosities. Correlation analysis revealed that the lamellar structure, crystalline structure, short-range ordered structure, and pasting viscosities of starch were the key factors affecting the dough's viscoelastic properties during irradiation treatment. • Irradiation reduced the elasticity and viscosity of the dough. • Irradiation reduced the crystalline lamellae thickness and crystallinity of starch. • Irradiation dissociated the double helix structure of starch. • The impact of starch structure on irradiated dough viscoelastic behavior was clarified.