RAPID OXIDATION OF COMMERCIAL EXTRA VIRGIN OLIVE OIL STORED UNDER FLUORESCENT LIGHT

Abstract

ABSTRACTExtra virgin olive oil is considered to be a high quality oil for health and nutrition and is widely consumed by the Mediterranean population. Presence of natural photosensitizers in olive oil may compromise its nutritional quality if stored in clear plastic or glass container under fluorescent light. In this study, the oxidative stability of commercial extra virgin olive oil (EVOO) and its chlorophyll and tocopherol stripped counterpart (SEVOO) stored at 60C in the dark and under fluorescent light (2650 lux) was evaluated. A column chromatographic procedure using silicic acid, Celite 545, activated charcoal and powdered sugar (sucrose), and eluted with hexane, provide an effective means for stripping extra virgin olive oil from its minor components. Minor components, mainly tocopherol and other phenolic compounds as well as carotenoids in SEVOO, influenced their oxidative stability in the dark. Meanwhile, natural pigments such as chlorophyll played a major role in the photooxidation of EVOO. Therefore, commercial extra virgin oil should be protected from direct light exposure in order to protect it from the oil from photooxidative deterioration.