Abstract: In order to reduce the weakening effect of soy protein hydrolyzate (SPH) on the gluten network in dough, texturized soy protein (TSP) and SPH (degree of hydrolysis of 4.54%) were blended and used to replace wheat flour at levels of 6.0% and 2.2%, respectively in dough preparation. Changes in noodle quality, gluten characteristics, farinographic properties, and dynamic rheological properties of dough were determined in comparison with control. Results showed that compared with control, the elasticity of the noodles with TSP-SPH decreased; the softening degree of the TSP-SPH incorporate dough decreased, while the farinographic evaluation score increased. The dry and wet gluten content decreased to 5.10% and 15.65%, respectively, while the gluten index increased to 89.24%. The storage modulus and loss modulus of the TSP-SPH incorporated dough increased, but the loss factor decreased. The content of glutenin macropolymer increased significantly. These results revealed that TSP-SPH promoted the formation of disulfide linkage between gluten proteins, thus lowering the weakening effect of SPH on the gluten network.

Key words: texturized soy protein, soy protein hydrolyzate, noodle quality, rheological properties, disulfide bond