Comparative study on yellow pea protein extracted with deep eutectic solvent: A novel and eco-friendly solvent in food processing

The growing demand for sustainable and efficient plant protein extraction methods has led to increased interest in alternative, eco-friendly techniques. Deep eutectic solvents (DES) have emerged as a promising green extraction technology, yet their impact on the structural, thermal, and techno-functional properties of yellow pea protein (YPP) remains underexplored. This study compares YPP extracted using DES (YPP-DES) with conventional methods, including salt extraction (SP), isoelectric precipitation (pH), and air clarification (AC), with commercial YPP (YPP-CO) serving as a reference. Protein purity (PP), yield (PY), and recovery rate (RR) ranged from 48.83% to 98.29%, 51.84% to 72.49%, and 13.23% to 19.70%, respectively (p<0.05). YPP-DES exhibited the highest PY and RR, while YPP-SP had the lowest. The denaturation temperature was lower in YPP-DES and YPP-AC (air-clarified YPP) compared to YPP-CO. Similarly, lightness was higher in YPP-AC compared to YPP-CO. However, yellowness was lower in both YPP-AC and YPP-DES. Emulsion activity index, emulsion stability index, and foaming capacities were superior in YPP-DES and YPP-SP compared to other methods (p<0.05). Regardless of the extraction method, freeze-dried YPP exhibited a sheet-like structure, whereas YPP-CO was spherical and hollow. These findings establish DES as a novel green extraction technique for YPP, achieving the highest PY and RR without compromising PP or techno-functional properties. 1. DES extraction enhanced yellow pea protein yield and recovery rate. 2. Techno-functional properties varied with extraction methods used. 3. Freeze-dried YPP showed a sheet-like structure, unlike commercial spray-dried YPP. 4. DES-extracted YPP retained high purity without compromising functionality. 5. DES proved to be a novel, green method for sustainable YPP extraction.