Allergy
Some people experience an anaphylactoid reaction to the consumption of strawberries. The most common form of this reaction is oral allergy syndrome, but symptoms may also mimic hay fever or include dermatitis or hives, and, in severe cases, may cause breathing problems. Some research suggests that the allergen may be tied to a protein involved in the ripening of fruits, which was named Fra a1 (Fragaria allergen1). Homologous proteins are found in birch and apple, which suggests that people may develop cross-reactivity to all three species.
White-fruited strawberry cultivars, lacking Fra a1, may be an option for strawberry allergy sufferers. Since they lack a protein necessary for normal ripening, they do not produce the flavonoids that turn the mature berries of other cultivars red. They ripen but remain white, pale yellow or "golden", appearing like immature berries; this also has the advantage of making them less attractive to birds. A virtually allergen-free cultivar named 'Sofar' is available.
Read more about this topic: Garden Strawberry