The Science Behind: Baking Powder and Baking Soda
Baking powder and baking soda are two powders that — although they appear to be identical — are slightly different. However, they both do the same thing: make baked goods fluffy.
Baking soda — or as it’s known by chemists, sodium bicarbonate — is the chemical compound that adds volume to baked goods and makes paper-mâché volcanoes explosive. To work its magic, baking soda is mixed with an acid such as vinegar, lemon juice, buttermilk, or cocoa powder. Once the baking soda reacts with the acid, the mixture begins to puff up. However, without an acid, the baking soda will never be activated, and your creation will be a disappointment.
Once the mixture is heated, more carbon dioxide gas is formed as the reaction between the baking soda and acid is accelerated. The carbon dioxide gas filters through the dough, searching for any pre-existing pockets of air. When it finds one, the carbon dioxide gas expands the pocket, causing the mixture to puff up. As the mixture stiffens and the carbon dioxide gas escapes, enlarged air pockets are left behind.
Baking soda is a base and raises a mixture’s pH when added. The environment the baking soda creates slows down protein coagulation — the stiffening of a food as it cooks or bakes— giving it more time to spread before it sets. This helps food bake more evenly.
Baking powder is one-fourth baking soda and three-fourths acid and cornstarch. Because of its composition, baking powder is only one-fourth as powerful as baking soda, but, when using baking powder, it isn’t necessary to add an acid. Instead, baking powder starts to work when any liquid is added.
The acid in baking powder is in the form of a salt, so it won’t react with the baking soda until a liquid is added. But once a liquid is added, carbon dioxide gas is produced immediately. Like with baking soda, it is important to bake the mixture right away, or else the mixture will collapse. Once the mixture with baking powder is put in the oven and exposed to heat, carbon dioxide gas is released and expands the mixture’s air pockets. When the mixture has stiffened, the enlarged pockets are left behind.
Now, with all this knowledge, it’s time to determine which should be used when. If you’re creating something where an acid is already one of the ingredients, use baking soda. However, if there are no acids in your recipe, use baking powder. Finally, if there are no acids or liquids, I would like to know what you are hoping to create.
Durand, Faith. “The Difference Between Baking Soda and Baking Powder.” Kitchn, Apartment Therapy, 29 Apr. 2010, www.thekitchn.com/pantry-basics-whats-the-differ-40514. Accessed 9 Sept. 2017.
Helmenstine, Anne Marie. “How Baking Soda Works for Baking.” ThoughtCo., 25 Aug. 2017, www.thoughtco.com/how-baking-soda-works-for-baking-607383. Accessed 9 Sept. 2017.
— -. “How Does Baking Powder Work in Cooking?” ThoughtCo., 20 Mar. 2017, www.thoughtco.com/how-baking-powder-works-607382. Accessed 9 Sept. 2017.
Moncel, Bethany. “What Is Baking Soda?” The Spruce, 27 Jan. 2017, www.thespruce.com/what-is-baking-soda-p2-1328637. Accessed 9 Sept. 2017.
Parks, Stella. “Cookie Science: How Baking Soda Works.” Serious Eats, www.seriouseats.com/2015/12/cookie-science-how-baking-soda-works.html. Accessed 9 Sept. 2017.
“What is baking powder, and how does it work?” HowStuffWorks, 14 Aug. 2008, recipes.howstuffworks.com/tools-and-techniques/baking-powder.htm. Accessed 9 Sept. 2017.
— Isabella S., Pennsylvania