Species identification in anchovy pastes from the market by PCR-RFLP technique

Abstract

The wide variety of marketed fishery products sometimes makes the recognition of species difficult, especially in processed food. So the consumer can be exposed to several commercial and health frauds. The European law obliges to indicate the species by specific commercial names only in fresh and prepared fishery products, but not in processed ones, in which the species can be named using generic denominations. In the present study, the use of a PCR-RFLP technique for species identification in anchovy paste, a widespread product in Italy, is described. After the PCR amplification of a common 272 bp fragment of mitochondrial cytochrome b gene from different fish species used as standards (European anchovy, European pilchard, European sprat, twaite shad, round sardinella, Atlantic horse mackerel and Mediterranean horse mackerel), the amplicons were digested using four restriction enzymes (MspI, HincII, Eam1104I and Alw26I). These patterns were compared with patterns from DNA extracted from anchovy pastes purchased from the market enabling to detect the presence of species different from anchovy ( Engraulis encrasicolus) in some of them. The suitability of extending the obligation to indicate the species using specific commercial denominations even to processed fishery products is also discussed.