Abstract: Deep-fried twisted dough sticks or Youtiao in Chinese were made from aluminum-free premix flour for deep-fried twisted dough sticks incorporated with different amounts (0%, 3%, 6%, 9% and 12%) of green wheat flour using different yeast starters: instant dry yeast H-1 (high sugar-tolerant Saccharomyces cerevisiae var. ellipsoideus), instant high-active dry yeast H-2 (high sugar-tolerant Saccharomyces cerevisiae var. ellisoideu), high-active dry yeast L-1 (low sugar-tolerant Saccharomyces cerevisiae var. willanus), and instant dry yeast L-2 (low sugar-tolerant Saccharomyces cerevisiae var. bayanus EC-1118). We studied the fermentation and rheological properties of doughs and the specific volume, texture characteristics and sensory quality of the resulting Youtiao. The results showed that H-2 had the best fermentation characteristics in terms of high elastic and viscous modulus and good viscoelasticity among four yeast strains. For each addition level of green wheat flour, the specific volume and elasticity of Youtiao made with H-2 was larger than those of Youtiao made with the other strains. The specific volume and texture quality of Youtiao made with 6% green wheat flour added were moderate; the sensory score was similar to that of the blank control while the contents of carbohydrate and dietary fiber were higher. Therefore, Youtiao made from H-2 fermented dough with 6% green wheat flour added had good sensory quality and was nutritious.

Key words: yeast, green wheat flour, fermentation characteristics, deep-fried twisted dough stick quality