A mechanistic kinetic model for lipid oxidation in Tween 20-stabilized O/W emulsions.

Models predicting lipid oxidation in oil-in-water (O/W) emulsions are a requirement for developing effective antioxidant solutions. Existing models do, however, not include explicit equations that account for composition and structural features of O/W emulsions. To bridge this gap, a mechanistic kinetic model for lipid oxidation in emulsions is presented, describing the emulsion as a one-dimensional three phase (headspace, water, and oil) system. Variation in oil droplet sizes, overall surface area of oil/water interface, oxidation of emulsifiers, and the presence of catalytic transition metals were accounted for. For adequate predictions, the overall surface area of oil/water interface needs to be determined from the droplet size distribution obtained by dynamic and static light scattering (DLS, SLS). The kinetic model predicted well the formation of oxidation products in both mono- and polydisperse emulsions, with and without presence of catalytic transition metals. • Mechanistic kinetic model describes lipid oxidation in oil-in-water (O/W) emulsions. • Compositional and structural features of O/W emulsions are included in the model. • Droplets with sizes <300 nm need to be accounted for in the model. • Kinetic rates of lipid oxidation vary with the droplet size. • Model provides good predictions for mono-and polydisperse emulsions. [ABSTRACT FROM AUTHOR]