The effect l-ascorbic acid on the rheological properties of soy–wheat dough: a comparison of raw and physically modified soy flours

Abstract

Farinograph and extensograph were used to study the effect of l-ascorbic acid and physical modification of soy flour on rheological properties of soy–wheat composite dough at various ratios up to 50% soy flour. Soy–wheat composite dough made from physically modified soy flour (PMSF) exhibited higher resistance to extension ( R m), greater tolerance to mixing, better mixing stability, higher water uptake and water absorption than the soy–wheat composite dough from raw soy flour (RSF). l-Ascorbic acid at 250 and 500 ppm improved R m, ( P < 0.05) of the dough made from the RSF and PMSF at 50% soy flour substitution for wheat. The same concentration of l-ascorbic acid decreased extensibility of the soy–wheat dough after 135 min of resting in both models ( P < 0.05).