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

• HSH is effective in modifying gel properties of acid-induced SPI gel.
• Particle size decreased and PdI increased in SPI dispersions due to HSH.
• The rheological properties, creep–recovery behavior of SPI gels were altered by HSH.
• Voids/pores in SPI gel was reduced and more compact gels were obtained due to HSH.
• Chaos/disorder in SPI gel network structure increased due to homogenization.

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.