DSC study of mixtures of wheat flour and potato, sweet potato, cassava, and yam starches

摘要

Differential scanning calorimetry (DSC) traces at a 30 wt% suspension were studied for mixture of wheat flour and following starches: potato (PS), sweet potato (SPS), yam (YS), and cassava (CS) at 10% to 50% starch. In the endothermal transition, the gelatinization peak temperature of the first peak (T_(P1)) was attributed to the wheat flour and that of the second peak (T_(P2)), to the starches. The T_(P1) of the control wheat flour was lower (62.6℃) than the T_(P2) of the control PS (67.1℃), SPS (77.6℃), YS (67.2℃), and CS (69.7℃). In the endotherm of the mixtures, the T_(P1) was always closer to that of control wheat (about 62℃). In contrast, the T_(P2) of the mixtures was always shifted towards higher values than those of the control starches. However, the T_(P2) was found to be lower as the starch in the mixtures was increased, and the values ranged from 68.6 to 69.4℃, 80.1 to 82.2℃, 69.3 to 70.7℃, and 73.3 to 74.3℃ for the wheat-PS, wheat-SPS, wheat-YS, and wheat-CS mixtures, respectively, at 10% to 50% starch. The apparent shifting towards higher temperatures resulted in a more prominent biphasic gelatinization behavior due to the influence of the wheat gluten in the mixtures of wheat flour and starches.