Integrated compositional and stable isotope fingerprinting coupled with multivariate chemometrics for the authentication and geographical classification of Tunisian monovarietal virgin olive oils
Microchemical Journal, cilt.228, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 228
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.microc.2026.118899
- Dergi Adı: Microchemical Journal
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, Chemical Abstracts Core, Chimica, Index Islamicus, Academic Search Ultimate (EBSCO), Engineering Source (EBSCO)
- Anahtar Kelimeler: Authenticity, LDA, Olive oil, PCA, Stable isotopes, Volatile compounds
- Çukurova Üniversitesi Adresli: Evet
Özet
This study provides a comprehensive characterization of monovarietal virgin olive oils (VOOs) from six Tunisian cultivars (Chemlali, Chétoui, Oueslati, Arbequina, Arbosana, and Koroneiki) across eleven geographical regions. Volatile compounds, fatty acids, triacylglycerols, pigments, total phenols, and sensory attributes were analyzed to establish cultivar- and origin-specific chemical fingerprints. Stable carbon isotope ratios (δ13C) were determined by cavity ring-down spectroscopy (CRDS) to assess environmental influence and support authenticity evaluation. A multivariate chemometric approach combining Principal Component Analysis (PCA), Hierarchical Cluster Analysis (HCA), and Linear Discriminant Analysis (LDA) was applied to 19 variables. PCA retained four components explaining 92.09% of total variance, clearly separating cultivars, particularly Chétoui and Chemlali oils. HCA confirmed four clusters reflecting genetic and environmental effects, and LDA achieved 100% classification accuracy under leave-one-out cross-validation (κ = 1.000), further confirmed by permutation testing (p = 0.001) and an independent sample-level validation (LOSOCV: 96.7%, κ = 0.918). Significant inter- and intra-cultivar variability was observed in lipid composition, phenolic content, volatile profiles, and isotopic signatures. Chétoui oils were characterized by higher oleic acid and phenolic levels, whereas Chemlali showed greater sensitivity to environmental conditions. Stable isotope analysis confirmed a C3 origin and was consistent with climatic variability. Overall, the integrated analytical and chemometric approach demonstrates that the combined use of compositional, isotopic, and multivariate statistical tools yields a promising candidate framework for authentication and traceability of Tunisian monovarietal VOOs.