Ability of surfactant hydrophobic tail group size to alter lipid oxidationin oil-in-water emulsions

Oxidation of oil-in-water emulsion droplets is influenced by the properties of the interfacial membrane surrounding the lipid core. Previous work has shown that an important factor in the oxidation of oil-in-water emulsions i s surfactant properties that impact interations between water-soluble proox idants and lipids in the emulsion droplet. The purpose of this research was to study the impact of surfactant hydrophobic tail group size on lipid oxi dation in oil-in-water emulsions stabilized by polyoxyethylene 10 lauryl et her (Brij-lauryl) or polyoxyethylene 10 stearyl ether (Brij-stearyl). The a bility of iron to decompose cumene peroxide was similar in hexadecane emuls ions stabilized by Brij-stearyl and Brij-lauryl. Oxidation of methyl linole ate in hexadecane emulsions containing cumene peroxide was greater in dropl ets stabilized by Brij-lauryl than in those stabilized by Brij-stearyl at p H 3 with no differences observed at pH 7.0. Oxidation of salmon oil was gre ater in emulsions stabilized by Brij-lauryl than in those stabilized by Bri j-stearyl as determined by both Lipid peroxides and headspace propanal. The se results suggest that surfactant hydrophobic tail group size may play a m inor role in lipid oxidation in oil-in-water emulsions.