Effects of the fermentation process on gas-cell size two-dimensional distribution and rheological characteristics of durum-wheat-based doughs

In this study, the effects of baker's yeast and sourdough fermentation on gas-cell size distribution and height of leavened doughs were evaluated in eight durum-wheat-based doughs of different strengths. Furthermore, the chemical and rheological properties of the doughs were analyzed to determine their effects on the leavening process. The gas-cell size distribution was modeled by a log-normal distribution across the full range of gas-cell sizes (10(-4) to 10(2) mm(2)), and by a power-law distribution for the large gas cells. The power law alpha exponent analysis of variance showed that alpha distinguished between the two empirical distributions, which indicated that there were more larger cells in the sourdough samples than in the baker's yeast samples. The distribution of the small-to-medium gas cells was the same for the two processes, as indicated by the log-normal parameters. The leavened dough height was generally higher for the baker's yeast dough samples, compared to the sourdough samples, except in the case of samples with very strong and elastic gluten. (C) 2012 Elsevier Ltd. All rights reserved.