Potassium Hydrogen Tartrate

Potassium hydrogen tartrate has been known for centuries. The ancient Greeks and Romans, who found it as a deposit from fermented grape juice, called it tartar. Today, cream of tartar is manufactured from the waste products of the wine industry. Waste products include press cakes from unfermented or partially fermented grape juice, dried slimy sediments from wine vats, and crystalline crusts from the wine vats used in second fermentations. The crystalline material is scraped off the sides of the vats and then purified to at least 99.5%.