Dynamic rheological behavior of wheat glutens during heating

Creep and dynamic rheological tests indicated that addition of redox additives directly into gluten or into flour before gluten extraction resulted in differences in rheological parameters. Heating from 30 to 50 degrees C caused a decrease in elastic modulus whereas heating above 50 degrees C strengthened the structure as evidenced by an increase in elastic modulus. Higher elastic modulus and lower creep compliance values suggested that Hereward gluten was more highly cross-linked than Riband gluten. Glutenin seemed to be affected more than gliadin during temperature sweep experiments. Both oxidising and reducing reagents showed similar weakening effects on gluten irrespective of addition into flour or gluten. Treatment with oxidising reagents, particularly bromate, slightly delayed the temperature for the increase in elastic modulus as assessed by temperature sweep experiments. The identical effect of reducing and oxidising reagents may be attributable to the differences in mode of action and intrinsic material properties. (c) 2005 Society of Chemical Industry.