Ultrafast PCR assay for identification of three king crabs—Chionoecetes japonicus, Chionoecetes opilio, and Paralithodes camtschaticus

Identifying the species of king crab in processed products is crucial to prevent food fraud and harm to consumers. A rapid real-time PCR method was developed to identify three crab species (Chionoecetes japonicus, Chionoecetes opilio, and Paralithodes camtschaticus) in crab products within 30 min. The method involved direct DNA extraction and utilized species-specific primer sets targeting mitochondrial cytochrome C oxidase subunit I (COI) and internal transcribed spacer (ITS1) for the three crab species. Specificity and sensitivity tests demonstrated consistent melting temperatures and cycle threshold values and a detection limit of 0.001 ng DNA. The ultrafast PCR successfully distinguished the three crab species in 24 commercial products, indicating its rapid, specific, and sensitive potential for on-site identification of crab species in commercial food products.