TRACEABILITY OF CITRUS FRUIT USING ISOTOPIC AND CHEMICAL MARKERS

The Italian citrus industry is currently involved in a marked crisis mainly related to the lack of a commercial strategy and to the expansion of the production of citrus fruits in other countries of the Mediterranean area, thus resulting in lower prices of the products in the market. This crisis can be overcome by focusing on typical citrus productions, which have been PGI (Protected Geographical Indication) recognized by the European Union. Therefore, it is necessary to implement a traceability system to verify the authenticity of these productions. The aim of this research was to classify, by a physicochemical and chemometric approach, two typical Italian citrus productions grown in Sicily (PGI ‘Arancia Rossa di Sicilia’ and PGI ‘Limone di Siracusa’) whose geographical origin was authenticated by samplings made in PGI and non-PGI areas. The combined use of physicochemical (quality parameter), spectral (NIR spectral patterns), multielemental (Fe, Zn, Mn, Cu, Li, Sr) and isotopic (¹³C/¹²C, ¹⁸O/¹⁶O) markers joined with multivariate statistical analysis such as PCA (Principal Component Analysis) and LDA (Linear Discriminant Analysis) was used as a tool to discriminate between PGI and non-PGI typical Italian citrus fruits. The results have revealed that a representative database of each geographical area can be used for the development of a traceability system of such typical productions.