Potential use of stable isotope and fatty acid analyses for traceability of geographic origins of jumbo squid (Dosidicus gigas).

RATIONALE

Squid is an important seafood resource for Asian and European countries. With the continuous development of processed squid products, an effective traceability system has become increasingly prominent. Here, we attempt to trace the fishery products of the main target species, jumbo squid (Dosidicus gigas), by using biochemical tracers.

METHODS

Carbon and nitrogen isotope ratios (δ C and δ N values) and fatty acid profiles were identified in squid from three harvest locations in the eastern Pacific Ocean by isotope ratio mass spectrometry and gas chromatography/mass spectrometry, respectively. Comparative analysis was used to evaluate the geographic variations in tracers and to identify the suitable discriminatory variables among origins.

RESULTS

Significant spatial variations were found in isotopic values and fatty acid profiles in squid muscle tissues, possibly because of different food availability and/or oceanographic conditions that each group experiences at a given location. The stepwise discriminant analysis indicated that δ N, C16:1n7, C17:1n7, C18:2n6, C20:1 and C20:4n6 were effective variables at differentiating origin.

CONCLUSIONS

Combined use of stable isotope ratios and fatty acid analyses could trace geographic origins of jumbo squid. This study provides an alternative approach for improving authenticity evaluation of commercial squid products.