Homemade baking powder

If you look at the label on your commercial baking powder, you'll most likely see that it's double-acting. This means that it becomes active at two points during baking, once when exposed to liquids and again when exposed to a heat source.

Homemade baking powder is single-acting. It activates upon exposure to liquids. Any products that you bake with single-acting baking powder will need to move from mixing to cooking/baking right away. This effect is more pronounced with something like a cake, than a batch of pancakes. (My last pancake in a batch comes out just as fluffy as the first.)

That said, there are some good reasons to mix up your own baking powder.

• you may have run out of baking powder and don't have time to rush out to buy more
• your baking powder may be past expiry and you don't want to "risk it" (to test, stir 1 teaspoon of baking powder into 1/3 cup of hot water; you should see very active bubbling right away)
• if you buy your ingredients smartly (in bulk, not those tiny little jars), you may save money by making your own baking powder
• you can avoid ingredients that you wish to minimize in your diet (aluminum and corn products, for example)
• the flavor in baked goods is better (some commercial baking powders leave a slight bitter after-taste)

The basic recipe for baking powder is:

1 part baking soda
1 part starch *
2 parts cream of tartar

* the starch can be corn starch, potato starch, tapioca starch or arrowroot. Make sure you are using "starch" and not "flour", for this part of the recipe.

I use arrowroot or tapioca starch, whichever I happen to have in my cupboard at the time. The addition of starch allows you to store your homemade baking powder for several months. Starch absorbs moisture, preventing activation of your baking powder while in the cupboard.

You can also make a substitute without the starch, one recipe at a time ( 1/4 teaspoon baking soda + 1/2 teaspoon cream of tartar = 1 teaspoon baking powder).


To have homemade, aluminum-free /corn-free baking powder on hand, I make about 1/2 cup at a time, following these measures:

1/8 cup baking soda
1/8 cup tapioca starch or arrowroot (potato or corn starch also works well)
1/4 cup cream of tartar

In a small bowl, I add the baking soda. I mash the lumps out of the baking soda with the back of a spoon. Then I whisk in the starch and cream of tartar.

For a uniform product, I then pass all of this through a sifter (a sieve or mesh strainer will also work). Use this measure per measure in recipes.

Store in an airtight jar. Homemade baking powder maintains it's maximum effectiveness for about 6 months. 

I occasionally find soft lumps in the baking powder. But these smash out with the back of the measuring spoon, as I'm scooping out what I need for a recipe.