Crab Allergy Test
Latin name: Chionocetes spp.
Source material: Boiled crab meat
Crab is a food which may result in allergy symptoms in sensitised individuals.
NB: Some species with similar names including hermit crabs, king crabs, porcelain crabs, horseshoe crabs, and crab lice are not true crabs.
Crab Allergy Test: Allergen Exposure
Crabs are crustaceans found throughout the world’s oceans as well as in freshwater and, in the case of some species, on land. They are covered with a thick exoskeleton, and have ten legs and a single pair of pincers.
Crabs are one of the most popular species of crustacean consumed by humans, making up one fifth of all marine crustaceans caught, farmed, and consumed worldwide. Total global consumption is in the region of 1.5 million tons per year.
The meat of the crab is prized for its soft, delicate and sweet taste. A distinction is made between white crab meat, which comes from the claws and legs of the crab, and brown crab meat, which comes from the body. The white meat is lower in fat, but the brown meat has a higher proportion of omega-3 fatty acids. The orange or yellow roe of the female crab can also be eaten, in a similar way to caviar.
The preparation of crabs for eating differs from region to region. Some species are eaten whole, while with others, only specific parts such as the legs or claws are used (this is particularly true for larger species). In the case of soft shell crabs, even the shell itself is eaten.
In Britain, dressed crab is a dish in which the meat of the crab is extracted, seasoned and then placed back in the shell for serving. In America, the meat is combined with egg white, cracker meal, mayonnaise or mustard to produce crab cakes. In France, a smooth, creamy, highly seasoned soup called bisque can be made from crab or lobster.
In Southeast Asia and the Indosphere, heavily spiced dishes such as masala crab and chilli crab are widely available.
Imitation crab, also called surimi, is made from minced fish meat that is crafted and colored to resemble crab meat, but does not usually contain true crab meat.
Exposure to crab allergens may also occur in occupational settings, such as via dust and waste water in factories producing seafood products.
Crab Allergy Test: Allergen Description
No specific allergens present in crab have been characterised, although a number of proteins have been identified.
Crab Allergy Test: Potential Cross-Reactivity
Common major allergens have been identified in crab, crayfish, shrimp and lobster.
Crab Allergy Test: Clinical Experience
Crab is a potent allergen, sometimes causing dramatic manifestations. It may also be considered an occupational allergen for workers in the food industry.
Fatal anaphylaxis after ingestion of crab has been reported.
A survey of food allergy in France showed crab to be responsible for 34% of the recorded reactions.
Shellfish is one of the more common food allergies, and usually persists throughout the patient’s lifetime. The majority of people (around 60%) of shellfish-allergic people experience their first allergic reaction as adults.
Symptoms can be severe and potentially life-threatening, including anaphylaxis. Even very small amounts of shellfish can provoke a reaction.
Exposure to the steam from cooking shellfish has been reported to cause an allergic reaction in some cases, due to the presence of allergenic proteins in the steam.
Seafood may contain high levels of histamine.