Sevim, DidarKadiroglu, PinarKoseoglu, OyaUyanik, Elif B.Telli Karaman, HanifeYaman, SenayIrmak, SahnurSusamci, ErkanOzturk Gungor, FeristeYildirim, AysenGurbuz Veral, MelekKaya, HulyaHakan, MehmetAsker, OzlemAltunoglu, Yesim2026-02-272026-02-2720260003-021X1558-933110.1002/aocs.70043http://dx.doi.org/10.1002/aocs.70043https://hdl.handle.net/20.500.14669/4648This study comprehensively evaluated the fruit and oil characteristics of 26 olive genotypes from 2016/17-2019/20. The research focused on physicochemical quality parameters and purity criteria to classify the oils as extra virgin olive oil (EVOO) and explore their genetic and biochemical diversity. All analyzed oils met EVOO standards for free acidity (<= 0.8% oleic acid), peroxide value, and UV absorbance (K232, K270), except one sample (Ters Yaprak). Phenolic content ranged widely (160.40-738.94 mg CAE/kg oil), correlating with oxidative stability (6.00-20.80 h). Oleic acid (65.29%-76.88%) and linoleic acid (5.63%-15.10%) were the dominant fatty acids, with variations linked to cultivar and climate. Total beta-sitosterol (93.59%-96.55%) and Delta 7-stigmastenol (0.18%-0.72%) were key markers for authenticity, though two samples exceeded Delta 7-stigmastenol limits. alpha-Tocopherol (159.91-423.48 mg/kg) was the primary antioxidant, with Memecik, Ayval & imath;k cultivars showing high levels. Phenolic content strongly influenced these attributes. Principal Component Analysis (PCA) revealed that phenolic content, oxidative stability, and fatty acid composition were the primary discriminators among cultivars. PCA results showed that variation in fatty acid, TAG, sterol compositions across 26 olive genotypes from 2016/17-2019/20 was primarily driven by genotype and harvest year, with no strong geographical clustering but distinct profiles for certain varieties such as Domat, Uslu, and E & scedil;ek Zeytini. Olive Varieties of the Aegean Region demonstrated exceptional quality, meeting EVOO standards with high phenolic and tocopherol content. Notable varieties such as Memecik, Ayval & imath;k exhibited superior oxidative stability underscoring their commercial and nutritional value. This study provides critical data for conserving genetic resources and promoting regional olive oils in competitive markets.eninfo:eu-repo/semantics/closedAccessAegean olive oilEVOOoxidative stabilityPCAphenolic compoundsArticle; Early AccessWOS:001667429700001