Structural, thermal, and physicochemical properties of ultrasound-assisted extraction of faba bean protein isolate (FPI)

Abstract

This study aimed to understand the impact of ultrasonication (24 kHz) at a fixed power (100 W) and duration (5–60 min) on the physicochemical, structural, and thermal properties of faba bean protein isolates. Ultrasound-relevant parameters such as acoustic density, intensity, and yield conversion were estimated. The average protein purity (∼85% protein) and yield (up to 22 %) of the ultrasound-assisted protein isolate were higher than those of the control protein isolate. Compared to the original flour, the isolate had significantly lower levels of vicine and convicine. Electrophoresis revealed no substantial alterations in the primary structure of the native and sonicated faba bean isolates. SDS-PAGE and SE-HPLC showed that sonicated samples had profiles similar to those of the native protein isolate. FTIR spectra and X-ray diffraction (XRD) patterns were used to measure structural changes in all faba bean protein isolates (FBPI). XRD study revealed two distinct diffraction peaks at 2 θ = 10° and 2 θ = 20° for protein isolates, indicating that alteration in native conformational crystallite size was altered after the ultrasound application.