Study on the changes of rheological properties during the production of sourdough whole wheat steamed bread made by retarded sponge-dough method

This study investigated the rheological properties of dough during the production of sourdough whole wheat steamed bread using the retarded sponge-dough method, with conventional whole-wheat yeast-fermented dough as the control. The findings revealed that during retarding, the extensibility properties of whole-wheat sourdough were significantly higher than those of wholewheat yeast-fermented dough (P<0.05). Additionally, the maximum compliance of whole-wheat sourdough was significantly lower, while the recoverable compliance ratio, zero-shear viscosity, and retardation time were markedly higher (P<0.05). These results indicated that whole-wheat sourdough exhibited a softer texture, enhanced elasticity and extensibility, and reduced susceptibility to breakage. During proofing, the extension distance and extension area of wholewheat sourdough were significantly greater than those of whole-wheat yeast-fermented dough, whereas the elastic modulus, viscous modulus, and maximum compliance were significantly lower (P<0.05). Furthermore, compared to the whole-wheat yeast-fermented dough, the maximum fermentation height and final fermentation height of whole-wheat sourdough were significantly higher, and the height loss rate was significantly lower (P<0.05). These findings demonstrated that sourdough possessed superior fermentation capacity, improved expansion effects, and greater resistance to external deformation. In summary, during retarding and proofing, the gluten network formed in whole-wheat sourdough displayed enhanced viscoelasticity, deformation resistance, tolerance, and gas retention capacity.