Potassium tartrate

Potassium tartrate, dipotassium tartrate or argol has formula K2C4H4O6. It is the potassium salt of tartaric acid.

To a small extent, potassium tartrate reacts with water to form potassium hydroxide and tartaric acid.

It is often confused with potassium bitartrate.

Potassium tartrate is the main compound of Weinstein, the sandy residue that form at the bottom of red wine bottles. It is usually only found in red wines of higher quality that have been made from grapes high in minerals and that have not been chemically stabilized.

As a food additive, its E number is E336.