CircRNA Profiling Enables Rapid Authentication of Duck Meat Adulteration in Mutton

To address meat adulteration, this study pioneers the use of ultrastable circular RNAs (circRNAs) as species-specific biomarkers for detecting duck meat adulteration in mutton. Three highly abundant duck-specific circRNAs with low cross-species homology were identified via high-throughput sequencing and bioinformatics analysis. Leveraging their unique BSJ, we developed a fluorescence-based dual-recognition platform combining BSJ-targeted reverse transcription rolling circle amplification (RT-RCA) with sequence-specific hairpin probes (HP). This RCA-HP system enables combinatorial hybridization and cascade amplification, achieving a detection limit of 0.1% duck meat in mutton. Notably, the target circRNAs demonstrated remarkable stability under harsh processing (180 °C frying and 121 °C autoclaving) and extended storage. Validation with 60 commercial samples showed 98.89% specificity and 99.26% sensitivity. The modular design allows easy adaptation to other meat species, establishing circRNAs as next-generation biomarkers and providing a robust framework for food authentication resistant to industrial processing.