Cream of Tartar

Many bakers believe that adding cream of tartar to egg whites lowers their pH and increases their acidity. The result is a physical reaction that makes it easier for the protein to stretch and extend yet maintain its stability. When I add cream of tartar to egg whites, it takes longer to whip the whites to the consistency I want, but the consistency of the foam is softer, making folding easier and smoother. The same is true when I add a small amount of sugar.

Cream of tartar’s real value, though, is evidenced in the oven, where the whipped egg-white foam is a main contributor to a batter’s volume and structure. The cream of tartar stabilizes the air bubbles in the heat, preventing them from collapsing before they set. When I tested these types of cake with and without cream of tartar, the results were dramatic. Using cream of tartar ensured greater volume.