FINS methodology to identification of sardines and related species in canned products and detection of mixture by means of SNP analysis systems

The sardines are a resource of great importance in the artisanal and industrial fisheries worldwide. Such sardines and sardine-type products are included many species of small pelagic species, all belonging to the Clupeidae family. Within this family, highlights the European sardine (Sardina pilchardus), which by its organoleptic characteristics this species has gained an extraordinary commercial significance. In this work, an amplification of a fragment of mitochondrial cytochrome b marker and subsequent phylogenetic analysis (FINS: Forensically Informative Nucleotide Sequencing) were carried out to assure the correct labeling of sardine and sardine-type products. On the other hand, a single nucleotide polymorphism (SNP) analysis that allows detection of mixture of S. pilchardus and S. aurita in canned products was developed. After the application of this methodology to more than 80 available commercial samples can conclude that in more of 15% of the products analyzed, the name of the species displayed in the label was not in agreement with the identified species, also a one of these included in mixture of species. The main novelty of this work lies in the fact that have been included a long number of different species of sardines, many of which were not included in similar works up to date. Furthermore, this methodology allows identifying over 20 species of sardines and can be applied to all kinds of processed products, including those who have been subjected to intensive processing treatments, such as canned foods. Therefore, this molecular tool can be applied in questions related to correct labeling, traceability, fishery regulations, and commercial trade control of sardines and sardine-type products.