Effect of Temperature, UV, Sun and White Lights on the Stability of Olive Oil

The effects of temperature, UV, sun and white lights on the carotene value, stability and subsequent oxidation of olive oil have been investigated. Five different brands of olive oils were purchased from the local market. The oils were preserved in Pyrex test tubes in ultra low temperature refrigerator (4 °C), oven (72 °C), UV, sun, and white lights for one hour daily up to 14 days. The samples were analyzed using UV-visible spectroscopy and standard AOCS methods. The results suggested that carotene value showed a considerable variation in all the oils samples and treated conditions. The significant decreasing trend was observed in white light and oven treated samples, while UV and sunlight treatments were also effective and showed oxidation of different olive oils. Oxidation parameters like free acidity, peroxide and anisidine values represented similar trend in the deterioration of olive oils. Low temperature storage was found beneficial to olive oil; however, UV and sunlight are effective for depletion of carotenoids and consequent photo-oxidation