Photooxidative stability of stripped and non-stripped borage and evening primrose oils and their emulsions in water

Minor components in edible oils affect both their autooxidative and photooxidative stabilities. Thus, stripping of minor components may influence stability of oils being studied. The impact of natural endogenous pigments on photooxidative stability of stripped and non-stripped borage and evening primrose oils and their emulsions in water was studied. Peroxide values (PV) of non-stripped borage and evening primrose oils and their emulsions in water were significantly (P<0.05) higher than corresponding values for stripped oils and their emulsions in water. A similar trend was observed when considering hexanal contents of bulk oils and their corresponding oil-in-water emulsions. These results indicate that minor components, especially endogenous chlorophylls, play a major role in the photooxidation of borage and evening primrose oils and their emulsions in water. (C) 2002 Elsevier Science Ltd. All rights reserved.