Studying the Storage Duration Effect on Some Properties of Olive Oil Samples in Western Libya

Olive oil has high nutritional and therapeutic benefits compared to other vegetable oils due to its content of vitamins, unsaturated fatty acids and the antioxidants. This study examined the chemical properties of eight olive oil samples stored for periods ranging from 3 months to 30 years, collected from western Libya. The study assessed various quality indicators, including moisture content, acidity, peroxide number, saponification number, and reducing power, comparing them to the standards set by the International Olive Council. The results showed that the moisture content in two samples (3-year Yafran and 30-year Zawia) was within the permissible limit of 0.2%, while the rest exceeded it. Acidity levels did not surpass the 17% limit in any of the samples. Interestingly, the 30-year Zawia sample had the highest oleic acid content at 32%. Peroxide values remained below the 20 meq/kg threshold. The most significant finding was that the 30-year Zawia sample exhibited the strongest reducing power of 0.077 ± 0.7, highlighting olive oil's potential in protecting cells from chronic diseases and inhibiting the spread of cancer cells.