Effect of soy proteins on characteristics of dough and gluten

The object of this research was to compare the influence of different soy protein products on wheat dough and its gluten characteristics, including soy protein isolate (SPI), texturized soy protein (TSP) and hydrolyzed soy proteins (SPH), all of which with similar protein content. Addition of TSP could increase dough stability and gluten content, but gluten could not be detected when flour was fortified with SPH. During mixing, SPI tended to interact with SDS soluble wheat proteins, SPH tended to interact with SDS soluble and alcohol soluble wheat proteins, and TSP tended to interact with SDS soluble wheat proteins and TSP. A new protein component was observed from TSP fortified dough by SDS-PAGE. Disulfide bonds change confirmed the new linkage formation in blend dough. CLSM micrographs revealed that effect of SPI, SPH and TSP was different, and this difference was responsible for the change of gluten and dough characteristics.