The aim of this research is to find if there is direct evidence relating the fatty acid composition of olive oils to specific cultivars grown within a well-limited geographical region. To group olive oils according to their own cultivars,(13)C high-field nuclear magnetic resonance (NMR) and gas chromatography (GC) were used to analyze 60 extra virgin olive oils from the same Italian region (southwestern Sicily) obtained from four monovarietal cultivars. The (13)C NMR spectrum provides information about glycerol triesters of olive oils, i.e., about the acyl composition of major components and about the fatty acids' positional distribution on the glycerol moiety. GC gives the complete fatty acid profile of olive oil samples. Selection of NMR and GC peaks on the basis of their sensitivity to the different cultivars was performed by using multivariate analysis of variance (MANOVA). Principal component analysis, tree clustering analysis, multidimensional scaling (MDS), and linear discriminant analysis (LDA) were then performed on the MANOVA-selected peaks. Results obtained from (13)C NMR and GC techniques combined with the multivariate statistical procedure are in good agreement and prove the usefulness of fatty acids analysis to group the monovarietal olive oils belonging to the same cultivars. Grouping of olive oils according to their cultivars occurs for particular (13)C resonances all belonging to fatty chains in the sn 1,3 position of the glycerol moiety.

RESUMEN Aceites de oliva de Italia y Argentina: Estudios de RMN y cromatografía gaseosa.La espectroscopía de Resonancia Magnética Nuclear de alta resolución (RMN) y Cromatografía Gaseosa (CG) fueron utilizadas para analizar 16 monovariedades de aceites de oliva, obtenid a s d e a l g u n o s o l i v a r e s M e d i t e r r á n e o s c u l t i v a d o s contemporáneamente en campos experimentales localizados en Italia y en la región de Catamarca en Argentina.Estas muestras permiten estudiar diferentes condiciones pedoclimáticas en la composición de los aceite de oliva.La CG proporciona el perfil en ácidos grasos de los aceites de oliva y las técnicas RMN 1 H y RMN 13C suministran diferentes informaciones: el espectro RMN 1 H permite medir los componentes menores del aceite de oliva tales como β-sitoesterol, hexanol, trans -2 hexanol, formaldehido, escualeno, cicloartenol y ácido linolénico y el espectro RMN 13 C da información referente a los triésteres de glicerol de los aceites de oliva, por ejemplo, la composición y distribución de la posición acílica en el glicerol.Los datos de CG y RMN han sido sometidos a un análisis discriminante lineal (LDA) y a un análisis cluster en árbol (TCA).Un minucioso análisis de estos resultados ha permitido seleccionar olivares que han sido menos afectados por las condiciones climáticas presentes en la región de Catamarca. Los olivares seleccionados producen aceites de oliva que pueden mantener sus características Mediterráneas y pueden ser propuestos como plantas colonizantes en esta región silvestre de Argentina. PALABRAS-CLAVE: Aceite de oliva -Análisis estadístico -Cromatografía gaseosa -NMR. SUMMARYItalian and Argentine olive oils: A NMR and gas chromatographic study.

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Starch enzymatic degradation caused by endogenous hydrolases is studied by in situ NMR spectroscopy on a set of hard and soft wheat flours. The results obtained by two different techniques (HR-MAS and (1)H NMR in solution) are analyzed in terms of a Michaelis-Menten kinetic phenomenological model taking into account the presence of endogenous enzymes and their eventual inactivation. The parameters resulting from the best fit of all experimental data to the kinetic model equations are submitted to a multivariate statistical analysis to assess the role of the oligosaccharides release in distinguishing between hard and soft wheats.