ENHANCED PROFILE CHARACTERIZATION OF VIRGIN OLIVE OIL MINOR POLAR COMPOUND EXTRACTS BY COMPREHENSIVE TWO-DIMENSIONAL GAS CHROMATOGRAPHY WITH TIME-OF-FLIGHT MASS SPECTROMETRIC DETECTION

The Minor Polar Compounds (MPC) (free fatty acids, acylglycerols, aliphatic alcohols, sterols, triterpenic acids and phenolic compounds) of virgin olive oil (VOO) play not only an important role for health and sensory properties (strong antioxidants and radical scavengers) but have also been used as natural chemical markers to characterize the quality of VOO. The complexity of the MPC fraction has precluded its detailed characterization for better elucidation of potential key trace compounds (regardless the chemical class) that can be useful in assessing the authenticity or other quality claims in a ,foodomic’ approach. Reversed-phase HPLC with UV-Vis diode array detection (DAD) is challenged in the determination of the entire MPC profile because it is limited to compounds that absorb at selected wavelengths and is thus not suitable for free fatty acids, mono and diacylglycerols, and triterpenic acids. The use of a two-dimensional gas chromatograph/time-of-flight mass spectrometry (GC×GC/TOF-MS) approach was investigated in this work, in which the number of compounds (as TMS derivatives) were identified through the MS library. The GC×GC/TOF MS approach yielded a greater number of analytes to be profiled than the other instrumental methods used in this work. A novel approach to obtain a reliable screening of MPCs by GC×GC is also discussed.