Amateur bakers often wonder when to use cream of tartar and when to use baking soda. The two ingredients can even be listed in the same recipe together. Understanding how the two products are made and what chemical properties they possess can help you figure out which ingredient best suits your recipe. Using the right product will give you the ideal dough, batter or other food product.
About Baking Soda
Baking soda is made of sodium acetate. Most of the baking soda on the U.S. market is produced by the Arm & Hammer Co. from an ore called trona. Technology for isolating baking soda from seawater is still under development. When heated, baking soda breaks down into water, sodium carbonate and bubbles of carbon dioxide. However, to produce carbon dioxide quickly, baking soda must be wet and mixed with something acidic.
About Cream of Tartar
Cream of tartar is made of potassium bitartrate. It is a natural byproduct of wine-making that forms in fermentation tanks and can be purified into a bright white powder. Cream of tartar is acidic and when combined with baking soda and cornstarch, it forms baking powder.
Use in Batter and Dough
Baking soda produces carbon dioxide bubbles, which help dough to rise. However, it only does this when mixed with water and acid. Cream of tartar is acidic and therefore serves as the acid to help baking soda rise. When mixed together and moistened, the two begin to form bubbles immediately. This means you want to get your batter into the oven quickly. If the batter is already acidic, adding cream of tartar is not necessary.
Use in Other Foods
Cream of tartar is often used alone for purposes other than the production of carbon dioxide. It is found in many meringue recipes because it stabilizes egg whites and gives them volume. It also prevents sugar from forming crystals, making it useful in icing and syrups.
Evelyn Broderick has been a writer since 2004. Her work has been published by the Jewish Alliance for Women in Science. She holds a Bachelor of Science in chemistry and biology from Macaulay Honors College and is pursuing an M.D./Ph.D. in immunology at Sloan Kettering. She is also a member of the New York Academy of Sciences.