Citrats

Citrats, or citrates, are salts and esters of citric acid. In chemistry, citrate refers to the tricarboxylate anion derived from citric acid; citrate salts form when one or more protons are replaced by metal cations. Common citrate salts include sodium citrate (Na3C6H5O7), potassium citrate, calcium citrate, and magnesium citrate. Citric acid is triprotic; citrate can carry three negative charges, depending on the metal.

Citrates are typically highly soluble in water and are widely used as acidity regulators, buffers, and sequestrants. In the food industry they appear as E331 and its salts, contributing sourness and helping prevent spoilage by metal ions. They also act as emulsifiers and stabilizers. In medicine, citrate salts function as anticoagulants in blood collection and transfusion, and magnesium or calcium citrate are used as dietary supplements or laxatives. In laboratory settings, sodium citrate is used as a buffering agent in biochemical assays and as an anticoagulant for plasma samples. Industrially, citrates are produced by neutralization of citric acid or by fermentation.

Biologically, citrate is an essential metabolite in the citric acid cycle, formed from acetyl-CoA and oxaloacetate. Disruptions to citrate metabolism are linked to various diseases, but citrate salts are generally considered safe when used appropriately.

Citrats, by their many forms, refer to a broad class of chemical compounds with wide applications in food, medicine, and science.