Authentication of farmed and wild european eel (Anguilla anguilla) by fatty acid profile and carbon and nitrogen isotopic analyses

We determined fatty acid profile and protein carbon and nitrogen isotopic composition in muscle of wild and farmed eels, in order to discriminate the geographical origin of fish and their dietary habits. The samples were divided into groups according to the farm origin (Italy, Denmark and Netherland), the market size (capitoni and buratelli) and the farming system (pond, RAS, lagoon and wild). Biometric measurements, proximate composition analysis (moisture, ash, lipid and protein content), fatty acids profile and carbon and nitrogen stable isotopes measurements were performed. Statistical analysis was fulfilled to investigate the homogeneity of variance and the means distribution, including Principal Component Analysis and Partial Least Squares Discriminant Analysis. The results suggested that the different farming conditions represented the main factor affecting fish muscle composition. In this scenario, fatty acid profile and δ13C and δ15N values of the defatted muscle represented useful tools to distinguish between eels reared under different feeding regimes (wild vs captive-bred). No differences were found between eels reared in different farms.