ABSTRACTThe objective of this work was to prepare a soy‐fortified corn dough having the same rheological properties as the unfortified material. Water sorption isotherms and hydration kinetics of pregelled corn‐flour, corn‐soy and starch powder systems were investigated. The effect of adding processed full‐fat soy flour on hydration, reconstitution and rheological properties of dough systems were studied with Brabender Farinograph and Extensograph instruments. Soy flour imparted an undesirable plasticizing effect on pregelled corn doughs. Rheological properties of model dough systems were studied to solve this problem. Results indicated this effect could be reversed by the addition of pregelled tapioca starch as an elasticizing agent. A corn flour:soy flour:tapioca starch::60:30:10 mixture produced a dough with rheological properties similar to those of a corn flour dough.