Effects of moderate electric field on the structural properties and aggregation characteristics of soybean protein isolate. (December 2022)

• Record Type: Journal Article
• Authors: Wang, Hong; Wang, Ning; Chen, Xing; Wu, Zenan; Zhong, Wenya; Yu, Dianyu; Zhang, Hongwei
• Is Part Of: Food hydrocolloids. Volume 133(2022)
• Publication Date: 2022-12
• Subjects: Moderate electric field -- Ohmic heating -- Soybean protein isolate -- Protein structure -- Aggregation characteristic; Hydrocolloids -- Periodicals; Food additives -- Periodicals; Colloïdes -- Périodiques; Aliments -- Additifs -- Périodiques; Colloids; Food additives; Periodicals; Electronic journals; 664.06
• DOI: 10.1016/j.foodhyd.2022.107911
• Languages: English
• ISSNs: 0268-005X

Abstract

Abstract: The effects of moderate electric field (MEF) at different intensities (4–10 V/cm) on the structural properties and aggregation characteristics of soybean protein isolate (SPI) during ohmic heating (OH) were investigated. Fourier-transform infrared spectroscopy, fluorescence spectroscopy, and analysis of surface hydrophobicity and total free sulfhydryl groups showed that MEF treatments at 4 and 6 V/cm facilitated the unfolding of the protein structure, thus exposing more hydrophobic residues and enhancing surface hydrophobicity. Protein aggregation increased with the increase in electric field intensity, as demonstrated by the turbidity and particle size measurements, size exclusion chromatography, and atomic force microscopy. MEF treatments at 8 and 10 V/cm induced the formation of large, soluble aggregates dominated by disulfide bonds and hydrophobic interactions. Rheological analysis showed that the MEF treatments at 4 and 6 V/cm improved the gelation capacity. These results contribute to improving the understanding of the changes in structure and aggregation properties of SPI during MEF treatment and create opportunities to modify protein structure by MEF technology. Graphical abstract: Image 1 Highlights: The moderate electric field (MEF) changed SPI structure and induced aggregation. Changes of structure and aggregates were affected by electric field intensity (EFI). Lower EFI induced SPI unfolding to form smaller and uniformly distributed aggregates. Higher EFI resulted in larger aggregates and higher degree of protein denaturation.