Labelling compliance assessment and molecular authentication of Grilled Fish Products Sold on Chinese e-commerce: Traceability issues related to the use of umbrella trade names

The present study aimed to verify the labelling compliance, the accuracy of the trade names, and to molecularly identify 74 pre-packaged grilled fish products purchased online on Taobao, the largest e-commerce platform in China. The labelling compliance was assessed in the light of the Chinese standard GB7718-2011 for pre-packaged foods. Products identification was performed by DNA barcoding targeting two mitochondrial genes (COI and cytb) while, the accuracy of the trade name, was assessed by analysing the results obtained using the 'common name search tool' available on the FAO FishBase portal. The trade name reported on the label was considered: 1) species-specific when only a species resulted from the search; 2) genus specific when more than one species belonging to the same genus resulted from the search; 3) umbrella term when more than one species belonging to different genera and/or families and orders resulted from the search. These results were compared to the molecular results, and the products were declared not-matching if the molecular results did not match the scientific names obtained by querying the trade name to FishBase portal. All products were fully compliant to the national labelling standard. Species identification was achieved for 97.3% of the tissue samples tested belonging to 72 products by using the two targets (COI and cytb). All products were sold using 12 different trade names consisting of two generic not informative terms (marine fish, fish), seven umbrella terms (eel, anglerfish, sardine, Navodon, snapper, leatherjacket, lionfish) which framed the products in a taxonomic family/order or several taxonomic orders, two genus specific terms (Bombay duck, Yellow croaker) and one species specific term (Tanaka's snailfish). A final mismatching rate of 48.6% was highlighted. The lack of accuracy in the trade names utilization highlighted in this study may favor substitution phenomena with economic and potential environmental impact.