Multiplex-PCR Assay for Simultaneous Identification of Lamb, Beef and Duck in Raw and Heat-Treated Meat Mixtures

A multiplex PCR technique was applied for the simultaneous identification of duck, beef and lamb meats in meat mixtures. To simulate food adulteration, lamb and duck meat (10-0.5% each) were mixed into beef (80-99%) and beef and duck meat (10-0.5% each) were mixed into lamb (80-99%). Species-specific primer sets were designed from the cytochrome b gene of mitochondrial DNA. A universal 18S rRNA primer set was also applied as a positive control in the PCR reaction. The sizes of the PCR products for eukaryotes, lamb, beef and duck were 99, 133, 166 and 204 bp, respectively. All primer sets showed specificity in the PCR reactions using template DNAs from 16 animal species. The sensitivity for both single and multiplex PCR was 0.005 ng. The detection limit for target species in raw and heat-treated (100, 121 and 200C for 20 min) meat mixtures was 1%. This multiplex PCR method successfully discriminated raw and cooked lamb, beef and duck meat samples. Practical ApplicationsIn most food fraud incidents related to lamb and beef, duck meat was used as a contaminant. Validation of the stability of PCR detection after the heat-treatment of meat samples is important when the method is applied to analyze processed meat products or to monitor meat products in the market. The multiplex PCR assay developed in this study is a rapid and sensitive detection method for the simultaneous identification of lamb, beef and duck meats in both raw and heat-treated meat mixtures.