GC-RIS EVALUATION OF PHENOLIC-COMPOUNDS IN VIRGIN OLIVE OIL

A new gas chromatographic method for detection of phenolic compounds in virgin olive oils was developed. Identification of chromatographic peaks was made by mass selective detection. The presence of a main peak at m/z 192 or at m/z 280, related only to tyrosol and hydroxytyrosol, evident in the mass spectra of linked phenols, was very profitable for assigning the phenolic nature to minor polar compounds extracted by methanal from virgin olive oil. Twelve structures are possible, and some of them are deemed more likely on the basis of the chemical behavior of the compounds studied. The presence of a ligstrosid aglycon containing no carbomethoxy group and of oleuropein aglycon derivatives was evidenced.