EN
Polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) analysis was used to identify fish species and to perform their authentication in commercial seafood products. Universal primers were used for PCR amplification of 464-bp long fragments of the mitochondrial cytochrome b gene. The PCR products were digested with restriction enzymes AluI, HinfI, HaeIII, DdeI, NlaIII, HincII, and MboII. Sixty fish samples were obtained from the local markets in the Czech Republic. In 47 samples (78.3%), the results were in agreement with declarations of the producers and 10 samples (16.7%) contained other fish species. There were not great differences between fresh fillets (chilled, frozen etc.) and heat-processed foodstuffs (tinned, smoked, etc). The correct designation was in 72.3% and 81.6% of samples, respectively. Even if in three cases the analysis was unsuccessful the method is useful for the control of the adulteration of food with fish tissue content and in this way it contributes to better consumer awareness.