Citric acid as a food additive is typically grown on a mold medium. Citric acid in fruits is natural. Someone can be allergic to the food additive due to mold allergies and not be allergic to fruits with citric acid.

Citric acid comes from citrus fruits. Lemons, limes, cumquats, tango fruit, naartjies, oranges, blood oranges, grape fruits and everything citrus. That's where it gets derived from. All other fruits should be safe to eat.

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