Effects of Ultrasound-Assisted Electrolyzed Water Treatment on the Structural and Functional Properties of Rapeseed Protein Isolate

An investigation was conducted to determine whether ultrasound-assisted electrolytic water treatment improved the structural and functional properties of rapeseed protein isolate (RPI) compared to untreated and ultrasound alone. The results showed that electrolyzed water pH-shifting treatment led to a reduction in the average particle size of the isolate, partial unfolding of the protein structure, increased content of free sulfhydryl groups, and greater exposure of hydrophobic groups, while the combination of ultrasound treatment contributed to further reducing the isolate size, changing the secondary or tertiary structure, and exposing more hydrophobic (P < 0.05). Meanwhile, the electrolyzed water pH-shifting treatment significantly enhanced the solubility and emulsifying activity index of the isolate. The ultrasound-assisted electrolyzed water pH-shifting treatment further increased solubility, emulsifying activity index (EAI), and emulsion stability index (ESI) (P < 0.05). In summary, the combined treatment effectively unfolded the isolated rapeseed protein structure, enhancing its solubility and emulsifying properties while reducing the need for acidic or alkaline reagents in practical applications.