A survey of crustacean-like protein content in health foods

Abstract

Since epidemiological investigations in Japan have shown that the number of patients with a crustacean allergy, such as allergy to shrimp/prawn and crabs, has been increased, the Ministry of Health, Labor and Welfare in Japan has enforced the labeling of these crustaceans mandatory in June 2008. In this survey, the content of crustacean protein in 90 health foods was investigated using two kinds of ELISA kits for the detection of crustacean protein. Consequently, in the health foods which include the materials purified from crustacean such as chitosan and glucosamine, the crustacean protein was not detected. On the other hand, in the health foods which include insect materials such as the larvae of a bee and an ant, the protein which reacts to the ELISA kits for the detection of crustacean protein was detected with high frequency. In addition, we confirmed with the immunoblot analysis that the tropomyosin-like protein detected in the health foods which include insect materials can bind to IgE in serum of the patient with food allergy to crustacean. These findings suggest that those health foods might include crustacean tropomyosin-like protein and the protein might react to serum IgE antibody of the patient with food allergy to crustaceans.