DNA barcoding reveals fraudulent substitutions in shark seafood products: The Italian case of “palombo” (Mustelus spp.)

In food safety and traceability, consumers are more and more demanding about composition and provenance of processed seafood products. In the trade of many species, manufacturing alterations usually bring to the loss of any morphological diagnostic features of the species, enhancing the possibility of fraudulent substitutions and incorrect product labeling. In this study, we used a DNA barcoding approach to identify species substitutions cases in shark slices sold in Italy under the vernacular name of “palombo” (that is referred to the triakiids Mustelus mustelus and Mustelus asterias for the Italian regulation). We produced the coxI barcode sequence (550 bp long) for all the analysed specimens, and we compared them with reference sequences from different databases (GenBank and BOLD), using two bioinformatic identification methods, one of them developed in our laboratory. Results showed a high amount of commercial frauds rising the 80% of analysed “palombo” slices and highlighting a relevant economical impact for consumers.