Effect of fermentation process, wheat bran size and replacement level on some characteristics of wheat bran, dough, and high-fiber Tafton bread.

Abstract This study investigated the effects of different particle sizes of sterilized wheat bran (100–200, 200–300 and 300–400 μm), their replacement levels at 5, 10, and 15% (based on flour w/w) and also their fermentation by Saccharomyces cerevisiae PTCC 5052 on the qualities of Tafton bread. Measurements indicated how these parameters affected pH, TTA, phytic acid, protein, ash, fat, soluble and insoluble dietary fiber contents in sterilized wheat bran samples. The volume of dough samples and the sensory properties of Tafton bread samples were examined. The lowest amount of phytic acid (2.0 ± 0.12%) was observed in fermented sterilized wheat bran (FSWB) which had particle sizes of 100–200 μm (p<0.05). Also, the highest amount of soluble dietary fiber (6.7 ± 0.4%) was observed in FSWB which had particle sizes of 200–300 μm (p<0.05). The largest increase in dough volume (284.0 ± 4.9%) was observed in dough sample containing the FSWB which had particle sizes of 100–200 μm at the 15% replacement level (p<0.05). The Tafton bread sample that had been prepared with FSWB (200–300 μm and 15% replacement level (7.50 ± 0.54), tasted fresher according to sensory attributes after 24 h, compared to the control sample (5.80 ± 0.79) which had no sterilized wheat bran. Highlights • Yeast fermentation has a significant effect on changing the bran composition. • The fermentation of bran reduces the phytic acid content. • Fine sizes of fermented bran improve the dough volume at high substitution. • Physicochemical properties and replacement levels of bran affect bread acceptance. • Medium-size particles of fermented bran in bread can improve bread freshness. [ABSTRACT FROM AUTHOR]