Potassium bitartrate

Chemical salt used in cooking as cream of tartar

Potassium bitartrate, also known as potassium hydrogen tartrate, with formula KC4H5O6, is the potassium acid salt of tartaric acid (a carboxylic acid)—specifically, l-( +)-tartaric acid. Especially in cooking, it is also known as cream of tartar. Tartaric acid and potassium naturally occur in grapes; its crude precipitate form tartar or wine stone are byproducts of winemaking found deposited on top of must barrels which can be purified.

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