Study of oils from the protected denomination of origin “Siurana” using excitation-emission fluorescence spectroscopy and three-way methods of analysis

The production area of the Protected Denomination of Origin (P.D.O.) “Siurana” olive oils can be divided into two regions: “Montsant” and “Camp de Tarragona”, with different orography, soil characteristics and climatic conditions. As a result of these differences, the oils have variable stability. Here we show that excitation-emission fluorescence can detect these variations. Oils from the “Montsant” region (more stable) show more fluorescence intensity above 500 nm (due to vitamin E) and less below 500 nm (due to oxidation products) than those from the “Camp de Tarragona” region. Discrimination between oils from the two P.D.O. “Siurana” regions was achieved by means of discriminant unfold partial least squares regression, giving a percentage of correct classification of 94 % for “Siurana-Camp” and 100 % for “Siurana-Montsant” oils.