Citric acid is the acid mostly commonly found naturally in citrus fruit such as oranges, lemons and limes. The most commonly available form is the anhydrous form and it is typically as a powder or as a fine granular crystal.
Citric acid is very soluble in water and has a strong acid tart flavour. It is commonly used in fruit drinks and carbonated beverages at 0.25 to 0.4% (based on a ready-to-drink basis)
For fruit and jam applications it is often best to add citric acid as a 50% solution (50% citric acid, 50% water, heated to dissolve), instead of directly adding the powder.
It can also be used in combination with antioxidants in the processing of fresh frozen fruits to prevent discolouration.