Modification of pea protein isolates by high-intensity ultrasonication: Functional, structural and nutritional properties

Abstract

The current study aims to modify the functional, physical, structural and nutritional characteristics of pea protein isolate. High-intensity ultrasound treatment was used at 20 kHz frequency and 25 % amplitude for 10 (US10), 20 (US20), or 30 (US30) min. Results indicated that ultrasound application enhanced the protein solubility and zeta potential. When compared to control samples, the foaming capacity (FC) and stability (FS) as well as emulsion activity (EA) and stability (ES) were also increased from 157.5, 42.03, 46.25 and 53.75 % up to 182.5, 81.57, 72.50 and 67.50 %, respectively. Besides, particle size was found to be lower for ultrasound treated samples (92.9–131.1 nm) in comparison to that of untreated commercial pea protein isolate (161.9 nm). Moreover, while the bioaccessibility of pea protein in untreated sample was calculated as 28.90 %, ultrasonication increased the retention of pea protein up to 49.36 %. It can be concluded from the results that the ultrasonication process can be used as an advantageous, green and non-thermal tool for obtaining protein isolates with improved techno-functional properties and nutritional quality. Therefore, this treatment might improve the characteristics, and thus increase the utilization of plant-based proteins, especially pea protein, in various food systems.

Keywords

• Ultrasound
• Plant protein
• Modification
• Solubility
• In vitro digestion