Zitrat

Zitrat is the term used in German-language chemistry for citrate ion or citrate salts derived from citric acid, the triprotic weak organic acid found in citrus fruits. The citrate ion, C6H5O7^3−, is the fully deprotonated form and forms salts with metal cations such as sodium, potassium, calcium, and ammonium.

Common Zitrat salts include trisodium citrate, disodium citrate, potassium citrate, calcium citrate, and ammonium citrate. They are widely used as buffering and sequestering agents, as well as food additives. Zitrat salts also serve as anticoagulants in clinical blood collection tubes, where they bind calcium to prevent clotting.

Production and occurrence: Citric acid is produced industrially by microbial fermentation, typically with Aspergillus niger. Zitrat salts are formed by neutralizing citric acid with appropriate bases or by reacting citrate-containing solutions. In nature, citrate occurs in many fruits, especially citrus.

Applications: In food and beverages, Zitrat functions as an acidity regulator and stabilizer. In medicine and laboratories, citrate salts are used as anticoagulants, buffering agents, and complexing agents. Biologically, citrate is an intermediate in the citric acid cycle and can be transported to the cytosol for lipid synthesis.

Safety and regulation: Zitrat salts are generally recognized as safe for use in food and pharmaceuticals within regulated limits. High intake can cause gastrointestinal discomfort or metabolic disturbances; individuals with certain medical conditions or on specific medications should follow medical guidance.

See also: Citric acid; Citrate; Trisodium citrate.