title: Effects of metal chelator, sodium azide, and superoxide dismutase on the oxidative stability in riboflavin-photosensitized oil-in-water emulsion systems.
abstract: The effects of riboflavin photosensitization on the oxidative stability of oil-in-water (O/W) emulsions were determined using lipid hydroperoxides and headspace volatile analyses. The influences of a metal chelator, sodium azide, and superoxide dismutase (SOD) on oxidation pathways were tested to gain a better understanding of the role of transition metals, singlet oxygen, and superoxide anion, respectively. Emulsions with riboflavin and visible light irradiation had significantly higher lipid hydroperoxides and volatiles (p < 0.05) as compared to samples without light irradiation or riboflavin. The addition of ethylenediammetetraacetic acid (EDTA) decreased the formation of lipid hydroperoxides, hexanal, 2-heptenal, and 1-octen-3-ol in a concentration-dependent manner. Sodium azide, a singlet oxygen physical quencher, only inhibited the formation of 2-heptenal and 1-octen-3-ol. Overall, photosensitized riboflavin participated in both type I and type II pathways in O/W emulsions, and these pathways enhance the prooxidant activity of metals through their ability to produce lipid hydroperoxides and superoxide anion.
authors.affiliation: Department of Food Science and Technology, Seoul National University of Science and Technology, Seoul, Korea.
authors.forename: JaeHwan
authors.initials: J
authors.lastname: Lee
authors.forename: Eric A
authors.initials: EA
authors.lastname: Decker
mesh_terms: D002614:Chelating Agents / Q000737:chemistry*; D004655:Emulsions / Q000737:chemistry; D008027:Light; D010084:Oxidation-Reduction / Q000528:radiation effects*; D055668:Photochemical Processes; D010938:Plant Oils / Q000737:chemistry*; D012256:Riboflavin / Q000737:chemistry*; D019810:Sodium Azide / Q000737:chemistry*; D013482:Superoxide Dismutase / Q000737:chemistry*; D014867:Water / Q000737:chemistry*; D003313:Zea mays / Q000737:chemistry
chemical_list: D002614:Chelating Agents; D004655:Emulsions; D010938:Plant Oils; D014867:Water; D019810:Sodium Azide; D013482:Superoxide Dismutase; D012256:Riboflavin