Baking Soda vs Baking Powder: What’s The Difference?

Baking soda and baking powder are both used to make baked goods, but they’re not the same thing! So what’s the difference between baking powder and baking soda, and why do some recipes call for both? In this post, I’ll outline the properties of both baking soda and baking powder, and touch on their similarities while explaining how they differ. 

You’ll not only learn why some recipes call for both of them, but how to substitute one for the other as well. Finally, you’ll also learn super easy ways to test them for freshness to ensure that your baked goods turn out light, airy, and perfectly browned. So let’s dive in!

The Difference Between Baking Soda And Baking Powder

The main thing to understand about these two ingredients is that baking soda is NOT the same thing as baking powder, and they can’t be used interchangeably. While the are both white powders that can help create fluffy baked goods, they work in different ways that are important to understand.

Baking Soda

Baking soda, also called bicarbonate of soda or sodium bicarbonate, is a salt with a multitude of uses around the house. Commercial baking soda is typically made from soda ash or a mineral called trona, which is found in huge quantities in Wyoming.

Before baking powder was invented, baking soda was an important leavening agent in baking, but it only worked when combined with an acidic ingredient like vinegar, cocoa powder, brown sugar, yogurt, or buttermilk. As soon as baking soda meets an acidic ingredient, it starts a chemical reaction that produces carbon dioxide, helping the dough or batter to rise as long as it is baked immediately.

Baking Powder

Baking powder is similar in that it contains baking soda, but it also has acidic cream of tartar mixed in (and sometimes other ingredients like cornstarch.) Once a liquid is introduced to single acting baking powder, it works the same way as the baking soda/acid reaction described above, meaning the mixture needs to be baked right away in order for it to rise.

Double-Acting Baking Powder

Double-acting baking powder, as the name suggests, reacts twice — first when liquid is introduced, then again when the mixture hits the high heat of your oven. This useful double reaction makes it less important to get batter or dough in the oven right away. In fact, most modern baking powders are double acting, and say so right on the packaging.

How To Substitute Baking Soda Or Baking Powder

At some point in your life, you may have wondered whether you could use baking soda instead of baking powder, or use baking powder instead of baking soda. While they are not interchangeable, you can substitute one for the other if you know the following formulas and rules of thumb!

Substituting Baking Powder For Baking Soda

Pure baking soda is about three times stronger than baking powder in terms of leavening. So if a recipe calls for baking soda, but all you have is powder, you can substitute a tablespoon of baking powder for each teaspoon of baking soda. (Recipes that rely on baking soda for leavening will also call for an acidic ingredient, so you won’t need to worry about that.)

• 1 tablespoon (3 teaspoons) baking powder = 1 teaspoon baking soda

Substituting Baking Soda For Baking Powder

When a recipe calls for baking powder and all you have is soda, you can substitute baking soda for baking powder by using 1/4 teaspoon of baking soda plus 1/2 teaspoon of cream of tartar per 1 teaspoon of baking powder in the recipe.

• 1/4 teaspoon baking soda + 1/2 teaspoon cream of tartar = 1 teaspoon baking powder

Note: This mixture will not keep! You can use baking soda and cream of tartar as a substitute for baking powder as often as you like, but don’t mix them ahead of time or the reaction won’t work properly.

If you don’t have cream of tartar in the house, you can use 1 teaspoon of vinegar or lemon juice in place of the 1/2 teaspoon of cream of tartar. This may have an effect on the taste or flavor of your recipe, so you may need to adjust the sugar content in your batter or dough.

• 1/4 teaspoon baking soda + 1 teaspoon vinegar or lemon juice = 1 teaspoon baking powder

What About Cleaning?

Can baking powder be used the same was as baking soda in cleaning? You could use it in a pinch, but you’d have to use more of it, and it would be a lot less economical. There’s also the matter of having cornstarch and cream of tartar in there, and while you can use cream of tartar to clean things, it’s not normally mixed with baking soda in such applications.

Why Do Some Recipes Call For Both?

When recipes call for both baking powder and baking soda, it’s usually for one of two reasons — to preserve the flavor of a tangy ingredient (such as buttermilk or yogurt), or to promote browning.

Too much baking soda can neutralize an acid ingredient and take away its tangy flavor, so adding a bit of baking powder in recipes can help achieve the desired lift and flavor. On the other hand, adding a bit of baking soda in a recipe can shift the pH in a such a way that it browns better in the oven.

How To Tell If Baking Powder Or Baking Soda Is Fresh

Neither baking soda nor baking powder lasts indefinitely, so it’s important to know they’re fresh enough to use. Here are a couple of simple tests you can use to make sure your baking staples are suitably fresh.

How To Test The Freshness Of Baking Soda

Pour a bit of white vinegar into a small bowl, then add a small spoonful of baking soda. If the mixture bubbles up rapidly, the baking soda is still fresh and ready to use in recipes. If the mixture doesn’t react, it’s time to toss out the old baking soda (or use it for cleaning!)

How To Test The Freshness Of Baking Powder

Pour some warm water into a small bowl, then add a small amount of baking powder to it. The powder should fizz up a bit when it hits the water, indicating that it’s still active. If it doesn’t fizz or react much, toss it out and replace it.

Did you learn anything new about baking soda or baking powder?