Effect of yeast products on fermentation characteristics of frozen dough and quality of steamed bread

Abstract: In order to determine the yeast quality for making frozen dough and steamed bread better and more stable, we studied the changes of characteristics of fermentation and rheology of frozen dough made by Guoguang low-sugar high-activity dry yeast (No.1), Actis Mali Apple instant high-active dry yeast (No.2), Pinyi high-activity dry yeast (No.3), Mali high-sugar instant high-active dry yeast (No.4), Danbaoli high-sugar instant high-active dry yeast (No.5) and Angel high-sugar-intolerance high-activity dry yeast (No.6) The doughs which were frozen and stored for 35 days, were analyzed by dynamic rheometer and Rheofermentometer F3, and the texture, color, specific volume and sensory quality of steamed bread made by frozen dough were compared. The results showed that frozen doughs made from different commercial yeasts in different frozen time had different rheological properties and fermentation characteristics. After making steamed bread, their hardness, springiness, resilience, chewiness, lightness, redness, yellowness, specific volume and scores of sensory evaluation showed significant difference (P<0.05) among different yeasts. Their texture, color, specific volume and sensory quality were also significantly different (P<0.05) among different frozen time for the steamed bread made by the same yeast. Frozen doughs made by No. 1 and No.2 always maintained higher fermentation activity, No. 6 had the most stable fermentation characteristics parameters of six kinds of yeasts during the frozen storage of 35 days. Then frozen dough made by No.1, No.5 and No.6 had higher elastic modulus and viscous modulus, No.5 had the most stable rheological properties. The steamed bread made by the frozen dough of No.1 and No.6 always had better sensory quality larger specific volume, better color, and better texture quality. Therefore the frozen dough and steamed bread made by No.1 had better quality and stability, followed by No.6. The results provide a theoretical basis for the selection of yeast in the industrial production of steamed bread made by frozen dough.