A Comparative Phytochemical Analysis of Olive Oils Derived From Two Underexplored Tunisian Cultivars: Chemchali and...

This study represents the first comprehensive investigation into the valorization of two rare olive cultivars, Chemchali and Fougi, cultivated in southern Tunisia. The main objectives were to assess the quality of their virgin olive oils (VOOs) by analyzing their chemical composition, sensory profile, quality indices, and physicochemical properties and to compare them to other VOOs from local well-known varieties. These two VOOs demonstrated prominent physicochemical characteristics, including free acidity levels below 0.3%, peroxide values under 10 meq O_₂/kg, and high oxidative stability. Gas chromatography revealed that oleic (62.52 ± 0.15 and 68.43 ± 0.20%), linoleic (14.47 ± 0.20 and 14.55 ± 0.12%), and palmitic (17.25 ± 0.12 and 11.90 ± 0.12%) acids were the dominant fatty acids in both oils. The major triacylglycerols identified included 1,2,3-trioleyl glycerol, 1-palmitoyl-2,3-dioleyl glycerol, (1-oleyl-2,3-dilinoleyl glycerol+1-linolenoyl-2,3-dipalmitoyl glycerol), and (1-stearoyl-2,3-dilinoleyl glycerol+1-palmitoyl-2-linoleyl-3-oleyl glycerol). β-Sitosterol was found to be the predominant sterol in both cultivars. Both oils presented physicochemical characteristics comparable to more common Tunisian cultivars, although with satisfactory yields. In conclusion, the studied cultivars exhibited a significant potential, producing high-quality edible oils. These findings suggest their suitability for large-scale cultivation, providing valuable alternatives or complements to conventional olive oil varieties.