Effect of Pea Legumin-to-Vicilin Ratio on the Protein Emulsifying Properties: Explanation in Terms of Protein Molecular and Interfacial Properties

[Image: see text] In isolates from different pea cultivars, the legumin-to-vicilin (L:V) ratio is known to vary from 66:33 to 10:90 (w/w). In this study, the effect of variations in the L:V ratio on the pea protein emulsifying properties (emulsion droplet size (d(3,2)) vs protein concentration (C(p))) at pH 7.0 was investigated using a purified pea legumin (PLF(sol)) and pea vicilin fraction (PVF(sol)). Despite a different Γ(max,theo), the interfacial properties at the oil–water interface and the emulsifying properties were similar for PLF(sol) and PVF(sol). Hence, the L:V ratio did not affect the pea protein emulsifying properties. Further, PLF(sol) and PVF(sol) were less efficient than whey protein isolate (WPI(sol)) in stabilizing the emulsion droplets against coalescence. This was explained by their larger radius and thus slower diffusion. For this reason, the difference in diffusion rate was added as a parameter to the surface coverage model. With this addition, the surface coverage model described the d(3,2) versus C(p) of the pea protein samples well.