Citric acid is a natural component and common metabolite of plants and animals. It is the most versatile and widely used organic acid in foods, beverages, and pharmaceuticals. Because of its functionality and environmental acceptability, citric acid and its salts (primarily sodium and potassium) are used in many industrial applications for chelation, buffering, pH adjustment, and derivitization. These uses include laundry detergents, shampoos and cosmetics, enhanced oil recovery, and metal cleaning. This article details its occurrence in nature, the physical and chemical properties of citric acid, and commercial manufacturing, processing, shipping, and storage information. Descriptions are given of the two common methods to recover citric acid from its fermentation broth: lime‐sulfuric acid recovery and also liquid extraction. Commercial considerations including worldwide production and U.S. distribution end use are reviewed. Various national compendial specifications for citric acid and common analytical test methods are discussed. Health and safety factors including environmental concerns are addressed.

Citric acid is a natural component and common metabolite of plants and minerals. It is the most widely used organic acid in foods, beverages, and pharmaceuticals. Because of its functionality and environmental acceptability, citric acid and its salts are used in many industrial applications for chelation, buffering, pH adjustment, and derivitization. These uses include laundry detergents, shampoos and cosmetics, enhanced oil recovery, and metal cleaning. This article gives details on the occurrence of citric acid in nature and its physical and chemical properties. Description of the two common methods to recover citric acid from its fermentation broth, lime‐sulfuric acid recovery and liquid extraction are given. Shipment and storage of citric acid are discussed. Various national compendial specifications for citric acid and common analytical methods are discussed. Citric acid as well as its common sodium and potassium salts forms, are considered Generally Recognized as Safe (GRAS). It is biodegraded by many organisms under aerobic and anaerobic waste water treatment conditions and in the natural environment.