The Olive Oil Marketing Regulation requires that olive oils of mixed origin have to be designated as either EU and/or non-EU origin. In this study 2H/1H, 13C/12C and 18O/16O ratios were analysed in bulk olive oils using isotope ratio mass spectrometry (IRMS) as well as 13C/12C and 2H/1H in the four main fatty acids (linoleic, oleic, palmitic and stearic acids) using IRMS coupled with GC (gas chromatography). The isotopic composition of olive oils was successfully used to distinguish samples originating in the two areas. When bulk data were combined with fatty acid isotopic data the differentiation power of the method was improved. The improvement is due to the specific isotopic fingerprint of the individual countries making up the EU and non-EU samples.
Read the abstract