Determination of trace elements in extra virgin olive oils: A pilot study on the geographical characterisation.

Abstract

Multi-element analysis of extra virgin olive oils from two Protected Designation of Origin each one belonging to two different Spanish province, Granada and Jaén, was carried out by ETA-AAS previous sample dilution with methyl-isobutylketone. Analytical conditions were optimised and reliability of the method was checked. Cu, Cr, Fe, Mn and Ni are the trace elements observed with corresponding values 14.28 ± 11.16, 27.31 ± 20.91, 91.70 ± 64.48, 34.60 ± 15.08 and 19.49 ± 10.08 μg/kg. Their statistical description shows their important variability even being under the international standards. Moreover, there were found significant differences between Cu, Cr, Fe and Ni content according to the geographical origin of the oils but not for Mn content. A multivariate discriminant analysis was performed so 95.55% of the samples were correctly classified. Then, the dependency of the trace element content of extra virgin olive oils on their geographical origin can be used for their local characterisation.