Is Your Baking Powder Still Good? Here's How to Tell
There's an easier (and more effective) way than simply reading the date on the label.
Baking powder is on the short list of essential kitchen pantry ingredients, especially for avid home bakers. If that description fits you and your culinary habits, chances are you use baking powder so frequently that you have to replace it long before the expiration date on the package matches the date on your calendar. If you only bake occasionally, you may be discouraged when your cake falls flat. You might even blame your lack of skills for the failure to rise, rather than a fairly common kitchen mishap. It could be that your baking powder (or baking soda, but that's another story) has lost its leavening power, and you had no idea of knowing because you use it so rarely. Don't be so hard on yourself! Check the baking powder to see if the fault lies therein.
How Can You Tell If Baking Powder Has Lost Its Power?
Regardless of what the package lists as the expiration date, a simple test should help you determine whether it's still good enough to give your cakes, cookies, pancakes, and muffins a lift. The powder is activated when it's exposed to moisture in a batter, and again once the batter hits the heat of the oven (this explains the term "double-acting" on the label).
To see if your powder is still good, drop about a teaspoon or so (no need to measure precisely here) into a small bowl of hot water. You should see a healthy amount of bubbles right away. If not, the baking powder has expired, and you should toss it and replace it with a new can.
What's the Best Way to Store It?
For best results, store your can of baking powder in an airtight container in a cool, dark spot, like a pantry or cupboard. Keep it away from heat or moisture, which will cause it to start activating before you even get to use it (this helps explain why some powders lose their activation powers before the date on the can). You may also wish to make your own baking powder if you can't run out and buy a new can—or if, like Chef Scott Peacock, you dislike the metallic taste that store-bought commercial baking powder can impart.
Whatever you do, don't try to use baking soda in place of powder. Each leavening agent is different and performs its own distinct functions in a recipe.