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). (D 2005 Elsevier Ltd. All rights reserved.