Effect of cavitation jet processing on the physicochemical properties and structural characteristics of okara dietary fiber

Abstract

The ability of cavitation jet processing to alter the structural and physicochemical properties of dietary fiber extracted from okara was examined. The impact of processing time (0 to 15 min) on the morphology and composition of the dietary fiber was monitored using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Atomic force microscopy (AFM), and Scanning electron microscopy (SEM). The water holding, oil holding, and swelling capacities of the okara dietary fibers were measured, which increased after processing, reaching values of 10.0 ± 0.2 g/g, 5.04 ± 0.07 g/g, and 13.9 ± 0.4 mL/g, respectively after 10 min. Cavitation jet processing had little impact on the total dietary fiber content, but increased soluble dietary fiber content more than 5-fold, which led to a pronounced increase in the shear viscosity. FTIR and XRD indicated that intermolecular hydrogen bonds and crystalline structures within the dietary fibers were disrupted by cavitation jet processing, while AFM and SEM indicated that there were appreciable changes in microstructure.