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 whole wheat 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 whole wheat 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 with the whole wheat yeast-fermented dough, the maximum fermentation height and final fermentation height of whole wheat sourdough were significantly higher, and the fermentation height loss rate was significantly lower (P<0.05). These findings demonstrated that sourdough possessed superior fermentation capacity and improved expansion effects, and exhibited greater resistance to external deformation. In summary, during retarding and proofing, the gluten network formed by whole wheat sourdough displayed enhanced viscoelasticity, deformation resistance, tolerance, and gas retention capacity.