Characterization of the Structure and Physicochemical Properties of Soluble Dietary Fiber from Peanut Shells Prepared by Pulsed Electric Fields with Three-Phase Partitioning

Abstract

This study evaluated the impact of pulsed electric fields (PEFs) combined with three-phase partitioning (TPP) extraction methods on the physicochemical properties, functional properties, and structural characterization of the soluble dietary fiber (SDF) derived from peanut shells (PS). The findings of this study indicated that the application of a PEF-TPP treatment leads to a notable improvement in both the extraction yield and purity of SDF. Consequently, the PEF-TPP treatment resulted in the formation of more intricate and permeable structures, a decrease in molecular weight, and an increase in thermal stability compared to SDFs without TPP treatment. An analysis revealed that the PEF-TPP method resulted in an increase in the levels of arabinose and galacturonic acid, leading to enhanced antioxidant capacities. Specifically, the IC50 values were lower in SDFs which underwent PEF-TPP (4.42 for DPPH and 5.07 mg/mL for ABTS) compared to those precipitated with 40% alcohol (5.54 mg/mL for DPPH, 5.56 mg/mL for ABTS) and PEF75 (6.60 mg/mL for DPPH, 7.61 mg/mL for ABTS), respectively. Notably, the SDFs which underwent PEF-TPP demonstrated the highest water- and oil-holding capacity, swelling capacity, emulsifying activity, emulsion stability, glucose adsorption, pancreatic lipase inhibition, cholesterol adsorption, nitric ion adsorption capacity, and the least gelation concentration. Based on the synthesis scores obtained through PCA (0.536 > −0.030 > −0.33), which indicated that SDFs which underwent PEF-TPP exhibited the highest level of quality, the findings indicate that PEF-TPP exhibits potential and promise as a method for preparing SDFs.