A novel reference real-time PCR assay for the relative quantification of (game) meat species in raw and heat-processed food

•Novel reference system for relative quantification of meat species in food.•Applicable to mammals and poultry species.•Applicable to raw and heat treated meat products.•Largely eliminates the bias obtained for heat treated food products.

In order to increase their profit, food producers may be tempted to replace expensive meat species by cheaper ones. Due to their selectivity and sensitivity, PCR based methods are frequently applied to identify and quantify meat species to detect food adulteration. Quantification of meat species in highly processed food products is, however, a difficult task. When we used a previously published reference system to relatively quantify the deer content in heat treated foodstuffs, we obtained recoveries that were substantially >100%. In the present study we aimed to improve the applicability of the reference system, targeting a 97 bp fragment of the myostatin gene, to heat treated products by reducing the length of the target sequence. The novel reference system, targeting a 70 bp fragment of the myostatin gene, was found to amplify the target region in 27 mammals and poultry species. Meat mixtures as well as raw and heat treated model sausages were analysed to demonstrate the applicability of the novel reference system for relatively quantifying the game meat content in processed food products. With the novel reference system, the bias introduced by heat treatment was largely eliminated.