Evaluation of the effect of adding α-amylase and ascorbic acid on rheological properties of wheat flour dough

One of the reasons of the bakery products poor quality and quality defection in the country is the low quality and the impropriety of wheat. Regarding the uncontrollability of so many effective factors in wheat quality. Using of improving agents in wheat flour has been highly considered. In this study, the effect of tow improving agents, ascorbic acid in three levels (20, 40, 60 ppm) and α-amylase enzyme in three levels (25, 50 and 75 ppm) over dough was investigated. Rheological tests results showed that increasing level of ascorbic acid from 20 ppm to 60 ppm is effective in dough stability time and dough developing time increment, reduction in dough softening degree, increasing elasticity, improving gluten structure and increasing the usage level of α-amylase enzyme from 25 ppm to 75 ppm is effective in the collapse of polymeric structure of starch, dough softening, stability, developing time and reduction elasticity characteristics. In simultaneous use of additives in constant amount of α-amylase enzyme, increase of ascorbic acid from 20ppm to 60ppm causes rheological individually betterness. Dough stability time, developing time and dough elasticity as well. This effect in constant amount of ascorbic acid shows a diverse relationship specially with high amount of added α-amylase (50 and 75 ppm). Generally, in addition to ascorbic acid containing treatment on its own using of α-amylase enzyme in 50 ppm level with 60 ppm ascorbic acid in improving the rheological and quality specialty of dough is suggested.