Origin of French Virgin Olive Oil Registered Designation of Origins Predicted by Chemometric Analysis of Synchronous Excitation-Emission Fluorescence Spectra NATHALIE DUPUY,* ,² YVELINE LE DRE Ä AU, ² DENIS OLLIVIER, § JACQUES ARTAUD, ‡ CHRISTIAN PINATEL, | AND JACKY KISTER ² Laboratoire GOAE, Universite ´ Paul Ce ´zanne, UMR CNRS 6171, case 561, 13397 Marseille Cedex 20, France; Laboratoire de Marseille, Direction Ge ´ne ´rale de la Concurrence, de la Consommation et de la Re ´pression des Fraudes, 146 traverse Charles-Susini, 13388 Marseille Cedex 13, France; Laboratoire de Chimie Analytique de l’Environnement, Universite ´ Paul Ce ´zanne, UMR CNRS 6171, IFR PMSE 112, B.P. 80, Aix-Marseille III, France; and Association Franc ¸ aise Interprofessionnelle de l’Olive, (AFIDOL), Maison des Agriculteurs, 22 avenue Henri-Pontier, 13626 Aix-en-Provence Cedex, France The authentication of virgin olive oil samples requires usually the use of sophisticated and very expensive analytical techniques, so there is a need for fast and inexpensive analytical techniques for use in a quality control methodology. Virgin olive oils present an intense fluorescence spectra. Synchronous excitation-emission fluorescence spectroscopy (SEEFS) was assessed for origin determination of virgin olive oil samples from five French registered designation of origins (RDOs) (Nyons, Valle ´ e des Baux, Aix-en-Provence, Haute-Provence, and Nice). The spectra present bands between 600 and 700 nm in emission due to chlorophylls a and b and pheophytins a and b. The bands between 275 and 400 nm in emission were attributed to R-, -, and γ-tocopherols and to phenolic compounds, which characterize the virgin olive oils compared to other edible oils. The chemometric treatment (PLS1) of synchronous excitation-emission fluorescence spectra allows one to determine the origin of the oils from five French RDOs (Baux, Aix, Haute-Provence, Nice, and Nyons). Results were quite satisfactory, despite the similarity between two denominations of origin (Baux and Aix) that are composed by some common cultivars (Aglandau and Salonenque). The interpretation of the regression coefficients shows that RDOs are correlated to chlorophylls, pheophytins, tocopherols, and phenols compounds, which are different for each origin. SEEFS is part of a global analytic methodology that associates spectroscopic and chromatographic techniques. This approach can be used for traceability and vindicates the RDOs. KEYWORDS: Virgin olive oil; synchronous excitation-emission fluorescence; PLS; quality control; origin determination; traceability INTRODUCTION The Mediterranean basin is the most important olive oil producing area in the world. Oils come from very many olive varieties, which are generally related to a soil that confers specific sensory and chemical properties. These characteristics are developed by attribution by national or European organiza- tions of mark of quality as the registered designation of origin (RDO) in France or the protected designation of origin (PDO) in Europe. In France, seven RDOs were recently created from two. The RDOs are regulated by specific articles and conditions that rule all of the official channels from growth to fabrication. Because of their high cost, notably with the RDO label, virgin olive oils could be the subject of fraudulent practices, which consist of mixing with various amounts of seed oils, low-cost olive oils, or olive pomace oils. Nowadays, one of the major problems in the agricultural-food industry is to set objective tools to determine the origin of primary materials as well as finished products so that we can follow the products from the producer to the consumer. The search for the origin and the authenticity of olive oils has been the object of numerous studies in the past few years using the extremely varied physical-chemical determinations that are associated with a chemometric treatment. The studies could be classified in two main categories. In the first one, the samples are chemically treated to determine the composition in different constituents: fatty acids, triacylglycerols (1, 2), sterols (3), aroma (4), etc. The second one is based on spec- troscopic studies on samples without preliminary treatment: 1 H * Corresponding author (e-mail nathalie.dupuy@univ.u-3mrs.fr). ² Laboratoire GOAE. § Laboratoire de Marseille, Direction Ge ´ne ´rale de la Concurrence, de la Consommation et de la Re ´pression des Fraudes. ‡ Laboratoire de Chimie Analytique de l’Environnement. | Association Franc ¸ aise Interprofessionnelle de l’Olive (AFIDOL). J. Agric. Food Chem. 2005, 53, 9361-9368 9361 10.1021/jf051716m CCC: $30.25 © 2005 American Chemical Society Published on Web 10/29/2005