E337 - Potassium sodium tartrate

Origin

Potassium sodium tartrate, also known as Rochelle salt, is a double salt of tartaric acid first prepared (in about 1675) by an apothecary, Pierre Seignette, of La Rochelle, France. It is synthesized by reacting tartaric acid with potassium hydroxide and sodium carbonate. It occurs naturally as a byproduct of wine production, being found in the sediments of wine vats.

Usage

In food, potassium sodium tartrate is used as an acidity regulator, antioxidant, and emulsifier. It can be found in processed cheeses, jellies, and margarines. It is also used as a stabilizer and thickening agent. Furthermore, it has applications in baking powders and as a component in Fehling's solution, used in chemistry for detecting reducing sugars. It is also used medicinally as a laxative.

Side Effects

Potassium sodium tartrate is generally considered safe for consumption in normal quantities. The EFSA has not established a numerical ADI ('not specified' is allocated to substances of very low toxicity). High doses may cause gastrointestinal distress, including nausea, vomiting, and diarrhea, due to its laxative effect. Individuals with kidney problems or electrolyte imbalances should exercise caution, as the potassium and sodium content could exacerbate these conditions. Allergic reactions are rare but possible.

Regulatory Status

Potassium sodium tartrate (E337) is approved for use as a food additive in the European Union. It is also generally recognized as safe (GRAS) by the U.S. Food and Drug Administration (FDA) under specific conditions of use. Its use is regulated to ensure that it is used at levels that are safe for human consumption.