What primarily differentiates a general intolerance to citron from a true citrus allergy?

Intolerance is often related to high acidity, whereas allergy involves specific immune protein reactions

It is essential to distinguish between a true immunological allergy and a general intolerance when adverse reactions occur after eating citron. A true allergy involves the immune system reacting inappropriately to specific proteins naturally present within the fruit, leading to symptoms that can include hives or severe swelling. In contrast, an intolerance or sensitivity is typically a non-immune reaction where the physical properties of the food are the issue; specifically concerning citron and related fruits, this often means experiencing heartburn or mouth soreness solely due to the presence of high levels of citric acid irritating sensitive tissues.