High-speed shearing of soybean flour suspension disintegrates the component cell layers and modifies the hydration properties of okara fibers

This study evaluated the feasibility of high-speed shearing (HSS) on the modification of okara fibers. Scanning electron microscope analysis suggested that HSS disintegrated and degraded the component cell layers at the cellular level. X-ray diffraction analysis showed that the reflection intensity of crystalline plane (I002) and the amorphous contribution (IAM) declined after HSS, confirming that the degradation of okara fibers was accompanied with the disintegration of crystalline as well as amorphous area. Moreover, the reflection intensity of cellulose's triclinic structure went up after HSS, which might be attributed to the breakdown of β-1, 4-glycoside bond. The swelling capacity and water holding capacity extensively declined (p < 0.05) from 5.5 mL/g and 8.5 g/g to 2.2 mL/g and 4.9 g/g after shearing, which was caused by the degradation of porous structure and the decrease of pore volume. HSS empowered okara fiber better solubility as well, and it might be achieved by breaking the cellulose-cellulose hydrogen bonds and redistributing the fiber composition from the insoluble to the soluble fraction. Consequently, HSS provided a cost-efficient way to disintegrate substrates and modify hydration properties of okara fiber, which possessed considerable application prospects in soy industry.