title: A strategy for simultaneous determination of fatty acid composition, fatty acid position, and position-specific isotope contents in triacylglycerol matrices by13C-NMR.
abstract: Triacylglycerols, which are quasi-universal components of food matrices, consist of complex mixtures of molecules. Their site-specific13C content, their fatty acid profile, and their position on the glycerol moiety may significantly vary with the geographical, botanical, or animal origin of the sample. Such variables are valuable tracers for food authentication issues. The main objective of this work was to develop a new method based on a rapid and precise13C-NMR spectroscopy (using a polarization transfer technique) coupled with multivariate linear regression analyses in order to quantify the whole set of individual fatty acids within triacylglycerols. In this respect, olive oil samples were analyzed by means of both adiabatic13C-INEPT sequence and gas chromatography (GC). For each fatty acid within the studied matrix and for squalene as well, a multivariate prediction model was constructed using the deconvoluted peak areas of13C-INEPT spectra as predictors, and the data obtained by GC as response variables. This13C-NMR-based strategy, tested on olive oil, could serve as an alternative to the gas chromatographic quantification of individual fatty acids in other matrices, while providing additional compositional and isotopic information. Graphical abstract A strategy based on the multivariate linear regression of variables obtained by a rapid13C-NMR technique was developed for the quantification of individual fatty acids within triacylglycerol matrices. The conceived strategy was tested on olive oil.
authors.affiliation: Research Unit: Technologies et Valorisation Agroalimentaire (TVA), Laboratory of Metrology and Isotopic Fractionation, Faculty of Sciences, Saint-Joseph University, P.O. Box 11-514, Riad el Solh, Beirut, 1107 2050, Lebanon.|EBSI team, Interdisciplinary Chemistry: Synthesis, Analysis, Modelling (CEISAM), University of Nantes-CNRS UMR 6230, 2 Rue de la Houssinière, BP 92208, 44322, Nantes cedex 3, France.
authors.forename: Noelle
authors.initials: N
authors.lastname: Merchak
authors.affiliation: EBSI team, Interdisciplinary Chemistry: Synthesis, Analysis, Modelling (CEISAM), University of Nantes-CNRS UMR 6230, 2 Rue de la Houssinière, BP 92208, 44322, Nantes cedex 3, France.
authors.forename: Virginie
authors.initials: V
authors.lastname: Silvestre
authors.affiliation: EBSI team, Interdisciplinary Chemistry: Synthesis, Analysis, Modelling (CEISAM), University of Nantes-CNRS UMR 6230, 2 Rue de la Houssinière, BP 92208, 44322, Nantes cedex 3, France.
authors.forename: Denis
authors.initials: D
authors.lastname: Loquet
authors.affiliation: Research Unit: Technologies et Valorisation Agroalimentaire (TVA), Laboratory of Metrology and Isotopic Fractionation, Faculty of Sciences, Saint-Joseph University, P.O. Box 11-514, Riad el Solh, Beirut, 1107 2050, Lebanon.
authors.forename: Toufic
authors.initials: T
authors.lastname: Rizk
authors.affiliation: EBSI team, Interdisciplinary Chemistry: Synthesis, Analysis, Modelling (CEISAM), University of Nantes-CNRS UMR 6230, 2 Rue de la Houssinière, BP 92208, 44322, Nantes cedex 3, France.
authors.forename: Serge
authors.initials: S
authors.lastname: Akoka
authors.affiliation: Research Unit: Technologies et Valorisation Agroalimentaire (TVA), Laboratory of Metrology and Isotopic Fractionation, Faculty of Sciences, Saint-Joseph University, P.O. Box 11-514, Riad el Solh, Beirut, 1107 2050, Lebanon. joseph.bejjani@usj.edu.lb.
authors.forename: Joseph
authors.initials: J
authors.lastname: Bejjani
mesh_terms: D066241:Carbon-13 Magnetic Resonance Spectroscopy / Q000379:methods*; D002849:Chromatography, Gas; D005227:Fatty Acids / Q000032:analysis*; D015999:Multivariate Analysis; D000069463:Olive Oil / Q000737:chemistry*; D014280:Triglycerides / Q000737:chemistry*
chemical_list: D005227:Fatty Acids; D000069463:Olive Oil; D014280:Triglycerides
keywords: Fatty acids; INEPT; Multivariate linear regression; Olive oil; Squalene; Triacylglycerol