Abstract

Six local varieties of olives were selected to study their oils and fatty acid composition, with the aim to determine one or several discriminating markers of the botanical origin. The relative percentages of fatty acids were well balanced, conferring to these oils high nutritional quality, characterized by important oleic acid content. The results showed the strongest effect of variety comparing to crop year and region which were less significant. We noticed that 80% of the fatty acids present clear differences between the various varieties population. Samples which present the highest level of oleic acid and mono-unsaturated fatty acids were Grosse du Hamma of first year with respective percentages of 79 and 85% and Azeradj for the same year with 77 and 78% respectively. Whereas, unsaponifiable minor components were present in very small quantities(ppm), but are sufficient to characterize and draw Nutritional and organoleptic olive oil profile. This is perfectly confirmed with principal component analysis results. Azeradj variety, in the four areas presented the highest rates of total tocopherol with averages between 251 and 271 ppm, tocophérol profile shows prevalence ofalpha tocopherol (95% of total fraction).

Key words: Olive oil, fatty acids, oleic acid, tocopherols, unsaponifiable.