Allergy to annatto, a natural colour additive
Ebo et al describe the case of a fifty eight year old man who experienced four episodes, in three years, of severe anaphylaxis with urticaria, angioedema and finally loss of consciousness within a few minutes after eating a sandwich or toast with Gouda cheese.
Testing confirmed that the problem was annatto (E160b).
Annatto is used to colour a range of food products including some types of cheese, margarine, butter, chips, rice, smoked fish and salad oils. Annatto is also a main ingredient in the Mexican spice mixture recado rojo, or achiote paste.
Ebo DG, Ingelbrecht S, Bridts CH, Stevens WJ.
Allergy for cheese: evidence for an IgE-mediated reaction from the natural dye annatto.
Allergy 2009 Oct;64(10):1558-1560.