Cream of Tartar speeds up the creation of foam and helps stabilize the structure of air bubbles. Read more
The most famous use for cream of tartar is to stabilize and increase the volume of egg whites when making meringues or soufflés. The cream of tartar also allows them to maintain their texture when whipped into stiff peaks, but it also increases their tolerance to heat. It also prevents sugar from crystallizing, so you can add it to your syrups, candies, caramels, frostings, gelatin desserts or baking products to give them a creamier texture. However, there are other food uses for cream of tartar, including stabilizing whipped cream and preventing discoloration of vegetables which have been boiled.