Analytical and Bioanalytical Chemistry

, Volume 409, Issue 1, pp 307–315 | Cite as

A strategy for simultaneous determination of fatty acid composition, fatty acid position, and position-specific isotope contents in triacylglycerol matrices by 13C-NMR

  • Noelle Merchak
  • Virginie Silvestre
  • Denis Loquet
  • Toufic Rizk
  • Serge Akoka
  • Joseph BejjaniEmail author
Research Paper


Triacylglycerols, which are quasi-universal components of food matrices, consist of complex mixtures of molecules. Their site-specific 13C 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 precise 13C-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 adiabatic 13C-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 of 13C-INEPT spectra as predictors, and the data obtained by GC as response variables. This 13C-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 rapid 13C-NMR technique was developed for the quantification of individual fatty acids within triacylglycerol matrices. The conceived strategy was tested on olive oil.


INEPT Multivariate linear regression Triacylglycerol Olive oil Fatty acids Squalene 



N.M. acknowledges the financial support of the Lebanese National Council for Scientific Research and the Research Council of Saint-Joseph University. The CORSAIRE platform from Biogenouest is also acknowledged. The authors acknowledge Anne Ancelin for linguistic assistance.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Supplementary material

216_2016_5_MOESM1_ESM.pdf (268 kb)
ESM 1 (PDF 267 kb)


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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Noelle Merchak
    • 1
    • 2
  • Virginie Silvestre
    • 2
  • Denis Loquet
    • 2
  • Toufic Rizk
    • 1
  • Serge Akoka
    • 2
  • Joseph Bejjani
    • 1
    Email author
  1. 1.Research Unit: Technologies et Valorisation Agroalimentaire (TVA), Laboratory of Metrology and Isotopic Fractionation, Faculty of SciencesSaint-Joseph UniversityBeirutLebanon
  2. 2.EBSI team, Interdisciplinary Chemistry: Synthesis, Analysis, Modelling (CEISAM)University of Nantes-CNRS UMR 6230Nantes cedex 3France

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