Tatar powder-chemical name is potassium tartrate, which is made by extracting Tatar with water and crystallizing. Colorless crystalline or white crystalline powder, soluble in water, insoluble in ethanol. A solid precipitate that precipitates when wine is made from tartar grape juice or other pulp juice. The main components are potassium hydrogen tartrate and a small amount of calcium tartrate. It can be treated with inorganic acid to produce tartaric acid.