Effect of induced electric field treatment on structural and physicochemical properties of wheat bran to enhance soluble dietary fiber content

Abstract

Improving the content and physicochemical properties of soluble dietary fiber (SDF) in wheat bran (WB) is conducive to enhancing the palatability and processing adaptability of bran-containing products. In this study, induced electric field (IEF) was employed for the modification of WB. The IEF modification conditions were optimized, and the effects on the structural and physicochemical properties of WB and its SDF were evaluated. The results showed that under the excitation voltage of 500 V, treatment time of 40 min, and NaCl concentration of 0.1 %, the SDF content in WB increased from 7.69 % to 12.02 %. The IEF-modified WB exhibited a porous structure and better hydration capabilities. Furthermore, the IEF modification resulted in a reduction in the crystallinity of WB, from 10.07 % to 9.06 %, and in the thermal stability, from 300.02℃ to 287.58℃ of the maximum decomposition. The SDF extracts study showed that IEF treatment destroyed the compact structure, reduced the thermal stability, and decreased the molecular weight and particle size from 1010 nm to 227 nm. In conclusion, IEF can effectively increase the SDF content and improve the quality of WB, which offers a theoretical reference for the comprehensive utilization of WB.