The effect of soluble dietary fiber from chia seeds on dough characteristics and steamed bread quality

The aim of this study was to investigate the effect of replacing medium-gluten wheat flour with different concentrations of chia soluble dietary fiber (C-SDF) on dough properties and the quality of steamed bread to treat dietary fiber deficiency among Chinese residents. The findings indicate that the mixed dough’s storage modulus (G') and loss modulus (G") increased with the increasing scanning temperatures but declined with the increasing shear stress. The secondary structures of dough proteins, including β-sheets and α-helices, exhibited a gradual increase in content as the C-SDF addition amount increased, followed by a decrease in β-turn structures. However, when the C-SDF addition amount reached 2.5%, the β-sheets and α-helices reduced dramatically, but β-turn structures increased, demonstrating that dietary fiber affected the compactness of the gluten network. As the quantity of C-SDF increased, the specific volume of steamed bread increased and then decreased; the height-to-diameter ratio increased; hardness and chewiness first reduced but later increased; and elasticity, cohesiveness, and adhesiveness first increased and then declined. The release of reducing sugars decreased, and sensory evaluation scores were first enhanced to 1.5% of C-SDF addition and then subsequently reduced. In summary, the findings of this study indicated that the optimal addition level does not exceed 1.5%.