“Citric acid is the compound 2-hydroxy-1,2,3-propanetricarboxylic acid. It is a naturally occurring constituent of plant and animal tissues,” according to the FDA.
This widely used preservative is an acid found in citrus fruits, as you may have guessed by the name. You may even be already using citric acid at home. Ever squirted lemon juice on something to keep it fresh longer?