The effects of geographical location on the chemical composition of olive oil of Zarazi cultivar growing in four different regions in the south of Tunisia (Sfax, Tataouin, Matmata and Medenin) were evaluated. Quality indices, oxidative stability, tocopherol content, fatty acid, sterol and phenolic compositions, were analyzed for each oil sample. Significant differences were detected depending on the growing area (p< 0.05). In general, the main secoridoids, were present in higher levels in the oil obtained from olives of Sfax region. Statistical analyses showed that acidic and sterolic compositions of olive oil were significantly modified according to the growing regions. The Principal Component Analysis of the different analyzed compounds indicated that the factor “geographical location” significantly affected olive oil quality, and highlighted the high quality of oil samples of Sfax, in terms of their high oxidative stability and their richness in bioactive compounds.

Keywords: fatty acids; geographical location; olive oil; sterols; phenolic compounds