Determination of crustacean allergen in food products by sandwich ELISA

Crustaceans are one of the most significant sources of food allergies, and tropomyosin is their major allergen. To detect crustacean allergens in food products, we have developed a sandwich ELISA using a crustacean tropomyosin-specific monoclonal antibody using black tiger prawn tropomyosin as an immunogen. Our ELISA showed 82-102% reactivity (based on reactivity to black tiger prawn tropomyosin) to tropomyosins from crustaceans including prawns, lobster, crab, hermit crab, and krill, while no substantial reactivity (0.1%) to those from mollusks, including squid, octopus, and shellfish, was observed. Furthermore, no positive ELISA results were obtained with any crustacean-free foods. Repeatability coefficients of variation (CVs) were 10%, and the detection limit based on a standard crustacean protein was 0.16 ppm, which qualified for the sensitivity requirements of the current food labeling system. The ELISA could detect crustacean tropomyosin, even heat-denatured tropomyosin, without being affected by food matrices. These results indicated that this ELISA is highly specific to crustacean tropomyosin, and will be useful as a method for detecting crustacean allergens in processed food products.