Evaluation of volatile metabolites as markers in Lycopersicon esculentum L. cultivars discrimination by multivariate analysis of headspace solid phase microextraction and mass spectrometry data

• Published in: Food chemistry 2014-02, Vol.145, p.653-663
• Main Authors: Figueira, José, Câmara, Hugo, Pereira, Jorge, Câmara, José S.
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Discriminant Analysis; Food Technology - methods; Food toxicology; Gas Chromatography-Mass Spectrometry; Gas-chromatography–single quadrupole mass spectrometry (GC–qMS); Headspace solid phase microextraction (HS-SPME); Lycopersicon esculentum; Lycopersicon esculentum - chemistry; Lycopersicon esculentum - metabolism; Lycopersicon esculentum L. cultivars; Medical sciences; Metabolomics; Multivariate Analysis; Principal Component Analysis; Prunus; Solid Phase Microextraction; Tomato; Toxicology; Vitaceae; Volatile metabolites; Volatile Organic Compounds - analysis; Volatile Organic Compounds - isolation & purification; Volatile Organic Compounds - metabolism
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2013.08.061

•Volatile markers of tomatoes from different cultivars Plum, Campari, Grape, Cherry and Regional.•Establishment of the volatile metabolomic expression by HS-SPME/GC–qMS.•Seventy-seven volatile metabolites, belonging to distinct chemical groups were positively identified.•Five of the 77 identified volatile metabolites are reported for the first time.•Differentiation between the fruits from Lycopersicon esculentum L. cultivars. To gain insights on the effects of cultivar on the volatile metabolomic expression of different tomato (Lycopersicon esculentum L.) cultivars – Plum, Campari, Grape, Cherry and Regional, cultivated under similar edafoclimatic conditions, and to identify the most discriminate volatile marker metabolites related to the cultivar, the chromatographic profiles resulting from headspace solid phase microextraction (HS-SPME) and gas chromatography–mass spectrometry (GC–qMS) analysis, combined with multivariate analysis were investigated. The data set composed by the 77 volatile metabolites identified in the target tomato cultivars, 5 of which (2,2,6-trimethylcyclohexanone, 2-methyl-6-methyleneoctan-2-ol, 4-octadecyl-morpholine, (Z)-methyl-3-hexenoate and 3-octanone) are reported for the first time in tomato volatile metabolomic composition, was evaluated by chemometrics. Firstly, principal component analysis was carried out in order to visualise data trends and clusters, and then, linear discriminant analysis in order to detect the set of volatile metabolites able to differentiate groups according to tomato cultivars. The results obtained revealed a perfect discrimination between the different Lycopersicon esculentum L. cultivars considered. The assignment success rate was 100% in classification and 80% in prediction ability by using “leave-one-out” cross-validation procedure. The volatile profile was able to differentiate all five cultivars and revealed complex interactions between them including the participation in the same biosynthetic pathway. The volatile metabolomic platform for tomato samples obtained by HS-SPME/GC–qMS here described, and the interrelationship detected among the volatile metabolites can be used as a roadmap for biotechnological applications, namely to improve tomato aroma and their acceptance in the final consumer, and for traceability studies.