Investigation of pork meat in chicken- and beef-based commercial products by ELISA and real-time PCR sold at retail in Kosovo

Food adulteration and fraudulent practices are widely observed in the food industry worldwide and are of great concern for Balkan countries. This study aims at investigating the level of undeclared pork meat in commercial beef and chicken meat products sold in Kosovo by implying one commercial enzyme-linked immunosorbent assay (ELISA) and two confirmatory real-time polymerase chain reaction (PCR) approaches [ready-to-use real-time PCR and real-time PCR with primers specific for pork mitochondrial deoxyribonucleic acid (DNA)]. In supermarkets in the capital city, Prishtina, 62 meat products were randomly sampled, and the three methods were applied. Additionally, these three approaches were evaluated for their practicability, reproducibility, and cost. The results showed that pork was present in 32% of beef- and 8% chicken-based products. ELISA and real-time PCR with pork specific primers showed 100% of reproducibility for beef- and chicken-based products. In contrast, the ready-to-use real-time PCR kit showed 100% reproducibility in chicken-, but only 75% in beef-based samples. ELISA was more rapid than both real-time PCR approaches, but it was more challenging when large numbers of samples were processed. The real-time PCR approach with pork specific primers was the cheapest, while the ready-to-use real-time PCR was the most practical method. Commercial ELISA, in combination with real-time PCR with pork specific primers, provides a reliable and affordable testing methodology that can be implemented for rapid detection and monitoring of pork adulteration in diverse commercial foods.