Emulsifying properties of extensively and mildly extracted pea proteins: A comparative study

• Different extraction methods affect pea protein composition and functional properties. • Mild fractionation preserves the native protein structure, 2S albumins and fibers. • Mild-fractionated pea protein fractions have superior solubility and emulsification. • Mildly and extensively extracted protein-based emulsions show similar tribological properties. • Mild-fractionated pea proteins are promising for plant-based emulsion applications. Plant-based proteins with their health and environmental benefits are emerging as an attractive solution to the growing global demand for proteins and sustainability. Different extraction methods of plant proteins significantly affect their components and functional properties. This study compares the structural and emulsifying properties of pea proteins obtained through the mild fractionation (water extraction, alkaline extraction, and air classification) versus the conventional alkaline extraction-acid precipitation. Results showed that while the isoelectric precipitated protein fraction exhibited higher purity (91.70%) compared with these mild-fractionated protein fractions (54-60%), the latter preserved the more native protein structure and retained 2S albumins and dietary fibers, resulting in significantly superior solubility, interfacial activity, and emulsifying properties. Although protein aggregates from isoelectric precipitation reduced emulsifying activity, they adsorbed onto oil droplets and improved stability at low protein levels. Interestingly, oral lubrication tests revealed no significant difference in friction coefficients before and after saliva addition for emulsions stabilized by these extensively and mildly extracted pea proteins. These findings demonstrate that the mildly fractionated pea proteins, with optimized functional properties and sustainability, present a promising clean-label alternative to the conventional extensively fractionated protein isolates for plant-based emulsion applications.