Tartaric acid, or cream of tartar, is the natural by-product of fermented grapes, collected from the wall of the casks used to age fine wines. Naturally reddish-brown in color, it’s carefully refined until it achieves its signature white color, earning it the name “cream” of tartar. Cream of tartar is a key ingredient in baking powder and adds a fluffiness and stability to egg white dishes such as meringues.
