What Is The Difference Between Baking Powder And Baking Soda?

When you're baking, do you wonder why some of our recipes call for baking soda, others for baking powder and some both (or none!)? Both ingredients are used as leavening agents in your baked goods; they enlarge the air bubbles that are created from whisking or beating to help your batter/dough rise during baking. This gives your finished product that light, crumbly and fluffy texture. But, since they both react a little differently they should not be used interchangeably. Here's why:

Baking Soda

Baking soda is the household name for sodium bicarbonate, an alkaline chemical compound that reacts with acidic liquids. In recipes, acids can include: lemon juice, sour cream, yogurt, buttermilk, vinegar and molasses. When baking soda reacts with acid, it releases carbon dioxide that help leaven the dough (think back to your eighth-grade volcano science project!). This is why recipes that have acidic ingredients call for baking soda rather than baking powder. Be careful though: too much baking soda in your recipe can actually leave a soapy taste.

Did you know?

Baking soda can help as an antacid to neutralize your stomach acid if you have acid reflux. Stir 1 tsp of baking soda in a glass of room-temperature water and sip. Baking soda can also help your food brown faster in a cooking chemical reaction called the "maillard reaction." It is the scientific term for what we sometimes call "browning" or "caramelizing". Adding a pinch of baking soda when sautéing sliced onions will help them brown faster!

Baking Powder

Baking powder is a combination of baking soda, an acidic salt (commonly cream of tartar), and cornstarch. It's typically used in recipes where there are little to no acidic ingredients. Instead, the baking soda and acid salt in the baking powder react with each other when wet. Because the powder needs a liquid in order to react, the cornstarch acts to absorb any moisture in the air before baking powder is added to your batter. Most baking powder in stores today is double-acting. This means the powder goes through two reactions: the first when it comes into contact with liquid, and the second when it comes into contact with heat. Single-acting baking sodas only require moisture to react.

Did you know?

To see if your baking powder is still active, mix 1 tsp with 1/2 cup hot water. The mixture should bubble immediately. Make your own baking powder by stirring 2 tsp cream of tartar with 1 tsp each baking soda and corn starch. Store it in an airtight container.

Tips:
1. Because both baking soda and baking powder start to react as soon as they hit moisture, it is best to mix your batter right before baking. This is why most recipes call for dry and wet ingredients to be separate. If you let your batter stand too long, it may cause your bubbles to deflate and flatten your final product.

2. Baking soda and powder should be stored in a cool, dry place to avoid any humidity.

Read more:
Plain yogurt vs. Greek yogurt
Cornmeal vs. polenta
Quick oats vs. large-flake oats

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