People often say baking is a science — and that’s the truth. Once you put your batter into a baking dish and into the oven, chemistry takes over. In most baking scenarios, it’s a reaction caused by chemical leavening agents (baking soda and baking powder) that makes your dough and baked goods rise. But what’s the difference between the two nearly indistinguishable powders? Let’s break it down.
First of all, what’s a leavening agent? Leavening agents are broken down into three categories: chemical, organic, and steam. Yeast is an example of an organic leavening agent — think baked yeast bread. Steam also makes dough rise — think puff pastry or pâte à choux. But since we are talking about baking soda and baking powder here, we are concentrating on chemical leavening agents. These work by causing a chemical reaction by releasing carbon dioxide gas, forming bubbles within the dough and causing it to rise.
Baking soda (sodium bicarbonate) is an alkaline and reacts with acids, like vinegar and more specifically buttermilk, sour cream, lemon juice, and yogurt in baking. These ingredients activate baking soda and if they're absent in your batter, the baking soda won’t react, meaning there will be no release of gas and the dough won’t rise. Baking soda is four times as powerful as baking powder.
Baking powder is basically baking soda with an acidic component already included. Most baking powders are double-acting, meaning that they only release a small amount of gas during the mixing process when moistened, but release the majority of gas in the oven as the temperature of the dough increases. Because of these two stages, baked goods with baking powder can stand for a while before being baked.
So, for baking, what do you need to know? Which ingredient you use depends on the other ingredients in the recipe. Baking soda will yield a bitter taste unless combined with an acidic ingredient. So, for example, don’t substitute baking powder for baking soda in buttermilk biscuits if you are swapping out the buttermilk for regular milk. And since baking powder has an acid and a base component, it works better in recipes that call for other neutral ingredients like milk.
Hopefully now you have a better understanding of the difference between baking soda and baking powder — and know when to use each one. Although baking is a science, you don’t have to be a scientist to understand the chemical reactions caused by each ingredient. Baking is fun, and the more you know, the better baker you will be!
Emily Jacobs is the Recipe editor at The Daily Meal. Follow her on Twitter @EmilyRecipes.