Ascorbic acid is a white, crystalline vitamin, C₆H₈O₆, found in citrus fruits, tomatoes, potatoes, and leafy green vegetables and used to prevent scurvy. The L-enantiomer of ascorbic acid it also called vitamin C. Ascorbic acid is a sugar acid with antioxidant properties. vitamin C it is water-soluble.

Ascorbic acid chemistry formula:

(R)-3,4-dihydroxy-5-((S)- 1,2-dihydroxyethyl)furan-2(5H)-one

Ascorbic acid is easily oxidized & so is used as a reductant in photographic developer solutions (among others) and as a preservative. Exposure to oxygen, metals, light, & heat destroys ascorbic acid, so it must be stored in a dark, cold, and non-metallic container. The name “ascorbic” comes from its property of preventing and curing scurvy. Primates, including humans, and a few other species in all divisions of the animal kingdom, notably the guinea pig, have lost the ability to synthesize ascorbic acid, & must obtain it in their food. Ascorbic acid and its sodium, potassium, & calcium salts are commonly used as antioxidant food additives. These compounds are water-soluble and thus cannot protect fats from oxidation: For this purpose, the fat-soluble esters of ascorbic acid with long-chain fatty acids (ascorbyl palmitate or ascorbyl stearate) can be used as food antioxidants.