Citric acid industrial production

In the last two decades, the citric acid industry has seen some major changes in ownership and expansions. The worldwide production stands at about 1 million ton a year. The major producers include the Swiss-based Jungbunzlauer, La Citique Beige/ Roche in Belgium, Bharat Starch Industries in India, and ADM, Cargill, and Tate Lyle in the United States. 

Citric acid is manufactured in over 20 countries with 1990 worldwide production estimated at approximately 550,000 t, distributed as shown in Figure 5. Most of this production is used for foods and beverages however, industrial appHcations, eg, detergents, metal cleaning, of citric acid are becoming more important on a worldwide basis. 

Citric acid is utilized in a large variety of food and industrial appHcations because of its unique combination of properties. It is used as an acid to adjust pH, a buffer to control or maintain pH, a chelator to form stable complexes with multivalent metal ions, and a dispersing agent to stabilize emulsions and other multiphase systems (see Dispersants). In addition, it has a pleasant, clean, tart taste making it useful in food and beverage products. 

Citric acid, which prior to 1922 was made entirely from citrus fruits and mainly in Italy, is now produced almost exclusively by the fermentation of sucrose by means of a mold, Aspergillus niger. At first pure sucrose was used for this process but more recently molasses has been used instead. Practically the whole of the world production of citric acid is used as such in medicinal preparations, in making soft drinks and in certain foods. The textile industries use small amounts, and it is also... 

Calcium carbide is used to produce acetylene. Some of the other chemicals made with lime include calcium hypochlorite, citric acid, and sodium alkalis. Lime is used to produce precipitated calcium carbonate (PCC), which is a fine-grained form of calcium carbonate. To produce PCC, lime is hydrated to produce slaked lime and the slaked lime is combined with water to produce limewater. Carbon dioxide is added to the limewater, causing calcium carbonate to precipitate as PCC. PCC is used widely in plastics production, papermaking, pharmaceuticals, and the petrochemical industry. 

Industrial citric acid production began in 1860 and for the next 60 years was dominated by Italian producers. The original production method was based on extraction from the juice of citrus fruits by adding calcium oxide (CaO) to form calcium citrate, Ca3(C6H507)2, as an insoluble precipitate that can then be collected by filtration. Citric acid can be recovered from... 

Citric acid and its citrate compounds are widely used in hundreds of applications. Global production of citric acid in 2005 was 1.6 million tons, with China producing approximately 40% of the world supply. In the United States, approximately 65% of citric acid use is in the food and beverage industry. Citric acid is used as an acidulant to impart tartness, to control pH, as a preservative and antioxidant, as a metal chelator, and to stabilize color and taste. Citrate salts can be used as mineral and metal dietary supplement for example, calcium citrate... 

Controlled Oxidative Fermentations—by which a number of industrial chemicals are produced. Citromyces. for example, can be used fur the production of citric acid from sugar. Aspergillus niger will yield oxalic acid by partial oxidative fermentation, but if the mold is permitted to remain in contact with the acid, il will convert it to carbon dioxide. 

Occurreace. IR-R. R (-Tartaric acid occurs in the juice of the grape and in a few other fruits and plants. It is not as widely distributed as citric acid or St- (-malic acid. The only commercial source is Ihe residues from the wine industry. The racemic acid is nut a primary product of plant processes but is formed readily from the dextrorotatory acid by heating alone or with strong alkali or strong acid. triewi-Tanaric acid is not found in nauire It is obtained from the other isomers hy prolonged boiling with caustic alkali. 

Fermentation industry. Primary metabolites of importance in ihe fermentation field include amino acids, purine nucleotides, vitamins, and organic acids. Specific products include citric acid, riboflavin (vilamin B>). and cubalamin (vilamin B12). Check alphabetical index pertaining lo specific vitamins. Of the secondary metabolites, antibiotics are Ihe mosl... 

The activity of chlorine as a bactericide is decreased by the presence of large quantities of algal slimes and certain process leaks (for example, hydrogen sulfide from petrochemical industries, ammonium compounds from fertilizer production, or citrates from the bioengineering manufacture of citric acid, but not hydrocarbon oil leaks from an oil refinery). 

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