A new real-time PCR quantitative approach for the detection of shrimp crustaceans as potential allergens

Allergy to crustaceans is an increasingly important food safety issue. To protect people from experiencing adverse allergic reactions, reliable methodologies are necessary to verify the labelling of processed seafood. In the present work, two new DNA-based approaches targeting the 16S rRNA mitochondrial gene are proposed to detect crustaceans in foods using a qualitative PCR assay specific for crustaceans (shrimps, lobsters and crabs) and a quantitative real-time PCR assay specific for shrimp crustaceans. The real-time PCR system allowed the detection and quantification down to 0.1 pg and 0.0001% (w/w) of shrimp DNA and shrimp in model mixtures, respectively. The method exhibited high performance for quantitative analysis in the range of 0.0001% to 50% as inferred by the calibration curve parameters being effectively validated with blind mixtures. The qualitative PCR assay can provide a simple, fast and high throughput tool for screening the presence of crustaceans in processed foods, while the proposed real-time PCR method proved to be a useful tool for the accurate detection and quantification of shrimp in foods at trace levels.