Application of multiplex PCR for the identification of grouper meals in the restaurant industry

Detection of fish species adulteration in the restaurant industry is important for consumer protection and confidence, and for an accurate implementation of the traceability for successful regulatory food controls. In this study, 37 purported grouper (Epinephelus marginatus) meals (20 from school and university lunch rooms and 17 from restaurants) from Madrid have been analysed by using multiplex PCR technology. Species-specific primers of the 5S rDNA gene (designed previously in another work) were used obtaining specific DNA fragments that could authenticate grouper meals; only 9 out of 37 samples were confirmed as authentic grouper. This genetic marker could be very useful for the accurate authentication of grouper meals in the restaurant industry.