Effect of mechanically modified wheat flour on dough fermentation properties and bread quality

The swelling properties and thus baking performance of starch strongly depend on mechanical starch modification (MSM), which can be influenced by grinding. To analyze the effect of starch influencing factors on dough fermentation properties and specific bread volume, different MSM levels were obtained using a ball mill. This treatment led to an increase in the water-holding capacity and a decrease in the beta-amylase activity of the flour. Baking tests were conducted with varied starch modification levels and water additions to analyze the effect of mechanical flour modification and the resulting changes in hydration and gas formation properties of the dough on bread quality. The specific bread volume was lower with high-MSM flour than with low-MSM flour, regardless of the adapted water addition. Therefore, the effect of MSM on dough fermentation properties was examined with respect to different water additions. Despite increasing the water addition, the time of porosity (Tx) of high-MSM dough was significantly lower than that of low-MSM dough. However, the amount of gas leakage after 60 min was quite low for high-MSM dough (gas retention coefficient similar to 99.5 %) and thus not considered significant. By adding 58 and 83 g water 100 g(-1) flour, the gas retention coefficient after 60 min was 100 %. The results also show that lower enzymatic activity with high MSM has no significant effect on the produced gas volume during fermentation. However, increasing MSM leads to a reduced dough height (Hm).