Effect of high shear homogenization on rheology, microstructure and fractal dimension of acid-induced SPI gels

High shear homogenization (HSH) (4000-16,000 rpm) was used to homogenize soy protein isolate (SPI) dispersions. These dispersions were subsequently gelled by acidification. The rheological properties, creep-recovery behavior, gel microstructure, fractal characteristics of these SPI gels were studied. The results showed that the application of high shear homogenization significantly (P < 0.05) decreased the particle size and lowered the polydispersity index of the SPI dispersions. The SPI gels produced by using the homogenized dispersions significantly (P < 0.05) increased the gel strength, increased the frequency dependence of elastic modulus and weakened the order and increased the chaos/disorder in the network structure. The application of high shear homogenization during dispersion stage also reduced the voids/pores in SPI gel microstructure and increased the gel compactness.