Methods to determine the geographic origin of EVOO are a useful tool to prevent fraud for this high value oil. Portuguese researchers have applied SIRA of carbon, oxygen and hydrogen (δ13C, δ2H and δ18O) with chemometrics to verify whether the geographical origin of VOOs obtained from three Mediterranean countries can be determined. One hundred and thirty eight authentic VOO samples were collected from Portugal, France and Turkey from two different harvest years (2016 and 2017). The samples were analysed for the isotopic ratios using an elemental analyser coupled to an isotope ratio mass spectrometer (EA-IRMS). Using meteorological and geographical parameters, a meteoric water line for olive oil from Portugal, France and Turkey, in two harvest years, were created to assess the impact of climate change on their δ2H and δ18O values. After principal component analysis, the VOOs from Portugal and France were well separated, Turkey slightly less so, but also the 2016 and 2017 harvest years of each country were also discriminated.
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