Abstract
Virgin olive oil was photooxidized at 2 and 40°C and at fluorescent light intensities of 0, 620, 2710, and 5340 lux. As expected, higher fluorescent light intensities induced higher peroxide formation in the oil. The thiobarbituric acid reactive substances (TBARS) were found to be good indicators of photooxidation during the early stage of the reaction. Pheophytin A and β-carotene were light- and temperature-sensitive, whereas α-tocopherol and total polyphenols were mostly affected by light. Pheophytin A functioned as a photosensitizer, resulting in rapid oxidation of the oil. β-Carotene was a strong natural inhibitor of photooxidation for all light intensities at 2°C, suggesting quenching properties for singlet oxygen. However, β-carotene antioxidant activity was reduced at 40°C because of its rapid destruction.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 837-843 |
| Number of pages | 7 |
| Journal | JAOCS, Journal of the American Oil Chemists' Society |
| Volume | 75 |
| Issue number | 7 |
| DOIs | |
| State | Published - Jul 1998 |
Bibliographical note
Funding Information:This study was published as paper No. 22,158 of the contribution series of the Minnesota Agricultural Experiment Station on research conducted under Project No. 18-084, supported by Hatch funds, and by the U.S. Agency for International Development, Contract No. 608-0160, IAV, Morocco Project, and a grant (E/1010-2) from the International Foundation for Science.
Keywords
- Pheophytin
- Photooxidation
- Polyphenols
- Virgin olive oil
- α-tocopherol
- β-carotene