The long and short of it is this: Yes, you can substitute baking soda for baking powder in most recipes. No, you cannot substitute baking powder for baking soda in most recipes.
What is baking soda?
Baking soda is a compound that can be naturally mined from the ground, but is most often created through a process using the mined product (Arm and Hammer). It’s used as a leavening agent in baking – that is, it reacts with acidic liquid to form gas bubbles, which then are baked into your product to make it lighter and fluffier.
The Best Baking Book on the Planet!
What is baking powder?
Baking powder is a mixture of baking soda, as well as cream of tartar and usually some starch. With baking powder, there’s no need to provide acid to the product to start a gas bubble reaction – the cream of tartar does that for you.
Baking powder comes in single-action and double-action. Double is the most common. Single action means that all the bubbles are going to form as soon as the product gets damp, so you have to work fast to preserve that lightness. Double action has a secondary reaction, so you have more to work with the product. Once it’s in the oven, the heat creates another bubble reaction.
You can make your own baking powder.
Just mix 1 teaspoon of baking powder, 1/2 teaspoon cream of tartar, 1/4 teaspoon of baking soda and 1/4 teaspoon cornstarch. This will give you single-acting baking powder. That means that once you add the powder, the bubbles will start to form, so GET THAT CAKE IN THE OVEN.
If you choose to make your own, make as small a batch as possible and store it in an airtight container in a cool, dark place – but not the refrigerator! Baking powder just doesn’t retain its “oompf” for very long, so you’ll be throwing it away quite often. To test if it’s still good, heat up some water and add a teaspoon of your powder to it. If it fizzes vigorously, it’s probably still good. If it just sits there – throw it out.
Another idea is to substituting baking soda for baking powder.
Natural versus “Unnatural” Soda
Natural soda versus the typical Arm & Hammer soda is just this: natural soda is mined directly from the ground from special sources; man-made soda is made through a chemical process out of similar ore that is mined from the ground. You can buy natural soda in most organic markets these days, and I recommend it. It’s like the Evian of the baking soda world!
Using soda in place of baking powder requires adjustments – the baking soda needs an acid to react with in order to form the little bubbles that cause your cake to rise. Baking powder already has that built-in. So if you substitute baking soda, use these items:
1 teaspoon of baking powder = 1/2 teaspoon of baking soda PLUS 1 1/2 tsp. lemon juice
You can also sub vinegar for the acid, or swap out 1/2 cup of the milk called for with 1/2 cup of buttermilk. All these will provide the acid you need to get the baking powder to “do it’s thing.” In any case, you need to get the product in the oven quickly, as bubbles will begin to form immediately upon adding the soda.
Baking in a kitchen is just like experimenting in a laboratory, so you need to keep notes on how something worked.