The Great Bake 
There’s nothing like that gut-wrenching feeling when you’re halfway through a recipe and realize you’re missing an ingredient.
So, if you don’t have time to run out to the store to get a new can of baking powder, it might get you wondering—can I use cornstarch instead of baking powder?
No, you shouldn’t use cornstarch instead of baking powder because they serve two different roles in baking. Whereas baking powder helps dough rise, cornstarch is a thickener.
But before you despair, there are many excellent substitutes you likely already have in your home.
Why Cornstarch Is a Bad Substitute for Baking Powder
Baking powder and cornstarch may look the same, but they’re chemically different.
Cornstarch comes from the endosperm of corn kernels. That’s the location of corn’s energy and is what makes cornstarch two times more potent than flour for thickening foods.
The issue with using cornstarch as a substitute for baking powder is that baking powder’s purpose is leavening, not thickening.
In fact, by putting baking powder in your baked goods, the goal is to make the batter airy and less dense. Baking powder achieves this thanks to it being composed of a base, acid, and buffer.
In fact, it’s the reaction of a base with an acid that may cause you to see bubbles when you add baking powder to a recipe. Your baked goods would come out of the oven dense and flat without it.
Is It Okay to Skip Baking Powder?
Rather than finding a substitute for baking powder, you might be wondering if it’s just better to skip it. After all, you can forgo certain ingredients, like spices in pumpkin bread, without destroying its taste.
Unfortunately, leaving out baking powder without substituting it for anything is a terrible idea.
Baking powder’s chemical bubble reaction is what gives baked goods their height. So, while your baked good will taste the same without baking powder, it will look and feel differently.
You don’t want to eat something that calls for baking powder without this ingredient, and it would be an embarrassment to serve such a dish if you’re planning on making it for guests.
Making Baking Powder at Home
If you run out of baking powder, leave your cornstarch in the cupboard and check if you have the following ingredients:
- Cream of tartar
- Baking soda
- Cornstarch
That’s right—cornstarch can aid in making a makeshift baking powder even though you should never use it in a 1:1 replacement ratio.
Instead, mix two parts cream of tartar to one part each of baking soda and cornstarch. The primary role of cornstarch in this mixture is to soak up moisture so that your homemade baking powder lasts longer.
Note that this is the best choice if you want to have a stash of baking powder in your house.
Other Baking Powder Replacements
Now that you know the answer to “Can I use cornstarch instead of baking powder?” is “no,” below are the many other ingredients you can use as a replacement.
Self-Raising Flour
Self-raising flour is one of the easiest substitutes if your recipe calls for flour. That’s because this flour already contains leavening agents.
In fact, most self-rising flour has baking powder mixed into it.
So, simply replace the standard all-purpose flour with the same amount of self-rising flour.
Baking Soda
Under normal conditions, baking soda is a bad substitute for baking powder. If your recipe doesn’t contain an acid, such as milk or lemon, it’ll create an off-putting metallic flavor.
However, if you’re in a bind, it’s okay to use one teaspoon of baking soda for every tablespoon of baking powder your recipe calls for. Yes, that likely means you’ll need to do some calculations, keeping in mind that there are three teaspoons in one tablespoon.
Additionally, you’ll need to add one teaspoon of an acidic ingredient like lemon juice or vinegar for every half teaspoon of baking soda you mix into the batter.
Should your recipe call for a smaller amount of baking powder, you can instead use a combination of ½ teaspoon of lemon juice and ¼ teaspoon of baking soda per teaspoon of baking powder.
As you’ll soon see, you can mix baking soda with several other ingredients to create a baking powder replacement too.
Molasses and Baking Soda
If your recipe already calls for molasses, you’re in luck—mixing ¼ teaspoon of baking soda with ¼ cup of molasses is equivalent to one teaspoon of baking powder.
That’s because this mixture reacts to encourage baked goods to rise in the oven.
However, you need to take care when adding molasses to your recipe. Because of how sweet this ingredient is, you should reduce the amount of sugar your recipe requires.
Yogurt and Baking Soda
If you have a tub of plain yogurt in your fridge, this is an excellent option. For each teaspoon of baking powder that your recipe calls for, you’ll need to mix ½ cup of yogurt and ¼ teaspoon of baking soda.
The reason this yogurt and baking soda combination works is because of yogurt’s acidic properties. When it mixes with baking soda, it creates bubbles that will keep your baked goods fluffy.
That said, adding yogurt and baking soda to a recipe takes practice, as you should reduce the number of other liquids you add to avoid your batter becoming soupy.
Cream of Tartar and Baking Soda
Cream of tartar is an acid, thanks to it being a byproduct of wine. When wine undergoes fermentation, it creates white sediment called tartaric acid. Manufacturers then collect, grind, and seal it with a cream of tartar label.
If you decide to use cream of tartar as a substitute, the best ratio is ½ teaspoon of cream of tartar and ¼ teaspoon of baking soda for each teaspoon of baking powder your recipe calls for.
Buttermilk and Baking Soda
Buttermilk’s sour nature makes it an excellent option for a baking powder replacement. It’s best to use buttermilk in recipes that call for a lot of liquids, given that you should reduce the number of fluids that go into the batter to combat a runny texture.
To use a buttermilk replacement, mix ½ cup of buttermilk and ¼ teaspoon of baking soda for every one teaspoon of baking powder.
How to Tell if Baking Powder Is Expired
One of the reasons you may contemplate a baking powder replacement is if you suspect that yours is too old. So, if you can’t find the expiration date or want to test if the powder is still good despite being expired, follow the steps below:
- Fill a cup with water.
- Add about ½ teaspoon of baking powder.
- Watch for a fizz.
If the baking powder fizzes, you can feel confident knowing it’ll work. Otherwise, if it doesn’t react with the water, it’s time for your can of baking powder to make a trip to the garbage can so that you can use one of the replacements listed above.
The Bottom Line
The next time someone asks you, “Can I use cornstarch instead of baking powder?” you’ll know how to answer them.
Although there are many homemade replacements for baking powder, the reality is that if you don’t have baking soda in your house, you’ll likely need to make a trip to the store either way.
