Cream of Tartar, common name for Potassium Bitartrate, also known as Potassium Hydrogen Tartrate, is a fine powder manufactured from natural raw materials. It is a byproduct of the winemaking process, a natural crystalline acid deposited on the inside of the wine barrels in cellars. Potassium bitartrate is the potassium acid salt of tartaric acid, a carboxylic acid. Potassium bitartrate crystallise in wine casks during grape juice fermentation, and can also precipitate in wine bottle. Potassium bitartrate is useful for stabilizing egg whites and increase both their volume and heat tolerance. It is also helpful in preventing sugar syrup form crystallizing.