1,1,3,3-Tetramethylguanidine (TMG), methanol and carbon dioxide were investigated as switchable polarity solvents (SPS) in the simultaneous derivatization and extraction of triacylglycerols for the gas chromatographic (GC) characterization of olive oil. Three commercial olive oils were used as test samples. Results of the developed method did not differ statistically from those provided by reference derivatization procedures. The transesterification reaction was carried out under a very mild condition, one step and in situ, and no particular matrix interferences were evidenced. The method represented the first example of the use of a switchable polarity mixture for the preparation of methyl ester derivatives of fatty acids (FAME).
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We thank our students Mohamed Gasser and Paolo Motta for their collaboration. This work was supported by University of Milano-Bicocca FAR 2012.
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