When the carrot allergen (called Dau c 1) is heated, it becomes safe for people with an allergy. But as soon as the temperature falls, it returns to its natural structure.
When the carrots are heated, only part of the proteins that cause allergic reactions is destroyed, says Birgitta Wöhrl, professor of biochemistry at the University of Bayreuth. This is why she generally advises people who are allergic to carrots to avoid carrots completely.
Both freshly cooked carrots and tinned carrots have the potential to trigger an allergy. “Foods containing carrot extract also pose an allergy risk”, explains Thessa Jacob, a biochemist in Bayreuth.
About the study
The carrot allergen Dau c 1 is a mixture of several proteins that are very similar in structure. The researchers heated these proteins up to a maximum of 95 degrees Celsius. They then investigated how the protein structures change as temperatures rise and fall. It was revealed that the mixture and nearly all the individual proteins can cause allergies again after they cool down to 25 degrees Celsius.