Life Hacks

The Surefire Way to Test Whether Baking Powder Is Still Good

March 19, 2018

You know that can of baking powder whiling away in your pantry? It says hi! It’s reliable and multipurpose and helps out with a teaspoon here, a tablespoon there. But, really, how long do you think you’ve had it? The leavening agent may have a long shelf life, but it’s definitely not immortal.

If you, like me, are a lackadaisical baker, you can probably stretch a can of baking powder anywhere from a year to...three (I’ve moved the same can across three different apartments). As expected, baking powder does go bad. Or rather, it loses its luster. The chemical compound—often a combination of baking soda, cream of tartar, and cornstarch—is only supposed to last somewhere from six months to a year. It’s sensitive to moisture, so any unexpected humidity could ruin your can. But don’t go running to the trash bin just yet!

Instead, try this test. It’s uber easy—you need only water—and will put to bed any fears that your baking powder has got to go. Also, it will keep you from whipping together muffins that refuse to rise. So what is it, you ask? Like I said, it’s simple. To check whether baking powder is still active, spoon a bit into a bowl (1/2 teaspoon will do) and pour in boiling water (1/4 cup will do). If the mixture bubbles, your powder’s good to go! If it doesn’t, your powder’s good to the trash. It won’t give your baked goods the rise they so desire. Opt instead for a new tin. Keep it stored with a tight lid in a cool, dry place, like a pantry.

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So there you have it: the baking powder test that will save you from yourself. Or at least from soggy cakes.

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See what other Food52 readers are saying.

  • BigSmiler
  • Cathy Whorf
    Cathy Whorf
  • Alice Baudoin
    Alice Baudoin
  • susan
  • Victoria Weinrich
    Victoria Weinrich
Valerio is a freelance food writer, editor, researcher and cook. He grew up in his parent's Italian restaurants covered in pizza flour and drinking a Shirley Temple a day. Since, he's worked as a cheesemonger in New York City and a paella instructor in Barcelona. He now lives in Berlin, Germany where he's most likely to be found eating shawarma.


BigSmiler April 5, 2022
All my comments are gone.
BigSmiler April 5, 2022
Extreme Flaw in all this is What About Half-Dead Baking Powder? It too will give bubbles. Not as many as fresh baking powder but how do we know that unless we also have a fresh can so we can do a side-by-side test. But in that case, why not just use the fresh stuff. There is a point when old baking powder will work if we Double the amount called for, but a test of "bubbles versus no bubbles" is not going to tell us that.
Cathy W. March 25, 2018
Use the out dated baking powder for cleaning drains or stick the box in the fridge or sprinkle it on rugs and furniture and vacuum up later. Don't waste it by throwing it away. It is also handy to sprinkle at your doorways to deter crawling bugs from entering your home. It is diatomaceous earth and it does wonders in the garden as well killing off those beetles that go after your lilies!
Victoria W. March 25, 2018
How can a mixture of baking soda,cream of tartar and corn starch be diatomaceous earth? DE is "FOSSIL FLOUR" which is powdered fossil shells.
BigSmiler April 5, 2022
Baking Powder is NOT diatomaceous earth.
Andrea W. January 1, 2023
You're confusing baking powder with baking soda.
Alice B. March 20, 2018
Instead of throwing away an old box of baking *soda*, I keep it next to my stove in case of grease fire. That way I have it right there if something goes wrong.
BigSmiler April 5, 2022
Alice B: I strongly suggest you try a test of this. Do a grease fire outside in a controlled environment and put old BAKING POWDER on it. This Article is Not about SODA and I don't want you misleading someone into thinking they are safer with the wrong stuff.
susan March 19, 2018
You did mean baking powder, right? You ended the piece saying it was a baking SODA test. Thanks.
Valerio F. March 20, 2018
good catch!