Light yellow light porous solid, odorless, insoluble in cold water, hygroscopic, and acidic in aqueous solution. It can form soluble complexes with potassium and calcium ions, which are easily decomposed into tartaric acid when heated too much.
Metatartaric acid is obtained by baking D-tartaric acid at 168～172℃ for 3.5h, or heating to 180～190℃, and then cooling naturally.
