The results were in agreement within 99% of confidence (t-test) with
those obtained by inductively coupled plasma optical emission spectrometry. The same grape, Cabernet
sauvignon, was used in all experiments, and the wines from each region were prepared especially for this
investigation in order to avoid any confusion due to grapes from other regions, which are often used in
commercial wines. The elements K, Mn, Rb and Sr were found to be the best indicators for the origin of
the wines, based on a Principal Component Analysis