A Rapid Detection Method for Salmonella Based on Real-Time Recombinase Polymerase Amplification in Food

This study developed a rapid detection method for Salmonella based on real-time recombinase polymerase amplification (real-time RPA). The method exhibited excellent specificity and could amplify target genes within 20 min at 39°C. It achieved a Limit of Detection (LOD50) of 47 CFU/mL. To evaluate detection performance, artificially contaminated food samples—including egg products, chocolate products, meat products, grain-based products, and soy products—were tested. Prior to real-time RPA detection, the samples underwent an enrichment step by shaking incubation at 36°C for 6 h. The real-time RPA method demonstrated consistent and robust performance across diverse food matrices, with relative LOD (RLOD) values below 2.5, satisfying the validation criteria outlined in GUOBIAO 4789.45 (GB 4789.45). A chi-square test conducted on bulk pork samples further confirmed no significant difference between the real-time RPA method and the GB 4789.4 standard method (p > 0.05). These findings highlight the potential of real-time RPA as a reliable and efficient alternative to GB 4789.4 for detecting Salmonella, enhancing food safety monitoring practices.