Tips & Techniques

Will it Fizz? How to Make Sure Baking Powder & Soda Are Fresh

March  9, 2015

Every week, baking expert Alice Medrich will be going rogue on Food52 -- with shortcuts, hacks, and game-changing recipes.

Today: Alice gets fresh -- with baking powder and baking soda, that is. 

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Frequent bakers keep baking powder and soda in the cupboard and use them, as a matter of course, well before their “Use By” dates. If you are a new or very occasional baker, here’s what you need to know. 

Baking Powder:
Once opened, baking powder should be stored airtight using the handy snap-on cover provided. Do glance at the (generally conservative) “Use By” date from time to time. If you doubt your powder or wonder if you can get by using it after the “Use By” date, you can test it as follows: 

Spoon or pinch a little powder into a tiny dish and pour a bit of warm or hot water over it. The mixture should bubble in a lively manner and you should hear the fizz. If there is no bubbling or it doesn’t seem lively -- or you are just nervous -- get a new tin rather than waste time and ingredients baking with pooped-out powder. 

Above: Baking soda on the left, baking powder on the right.

Baking Soda:
Received wisdom, and every baking site on the internet, will tell you that baking soda has a shelf life and will lose its potency similarly to baking powder. Some sources say it should be used within 18 months and that humidity can shorten its life. 

I’m not so sure about that...  

While I am very careful with my baking powder because I know it can go dead, I’m quite cavalier with my soda! All of these years I’ve been leaving the open package unsealed in the cupboard and I’ve never had a problem with performance. Ever. But then I began to wonder: Could the internet be wrong?

So I found an ancient box of soda open in the back of my fridge with a 2009 “Use By” date. It was a little clumpy due to the humidity (and heaven knows what else it was exposed to in my fridge). I put a giant pinch of it in a tiny dish next to another tiny dish with a giant pinch of the soda from my baking cupboard, which is fresher but opened and unsealed. (I may be devil-may-care with my soda, but even I don’t use the stuff that’s deodorizing my fridge for baking.) Since soda activates with acid rather than water, I spooned a little vinegar into each dish. Both samples bubbled and fizzed happily.  

Bottom line: Be vigilant with your baking powder; don’t worry too much about the soda.  

P.S. I can’t wait to hear what the seasoned bakers among you will have to say on this subject! 

Above: Baking soda and vinegar on the left, baking powder and warm water on the right. 

Photos by James Ransom

See what other Food52 readers are saying.

  • Danielle
  • Penny Hammack
    Penny Hammack
  • Nancy Herring
    Nancy Herring
  • Beehive Alchemy
    Beehive Alchemy
  • Jaye Bee
    Jaye Bee
My career was sparked by a single bite of a chocolate truffle, made by my Paris landlady in 1972. I returned home to open this country’s first chocolate bakery and dessert shop, Cocolat, and I am often “blamed” for introducing chocolate truffles to America. Today I am the James Beard Foundation and IACP award-winning author of ten cookbooks, teach a chocolate dessert class on, and work with some of the world’s best chocolate companies. In 2018, I won the IACP Award for Best Food-Focused Column (this one!).


Danielle April 20, 2020
My baking soda passed the fizz test, but my dough still didn’t rise enough! It is only 6 months past expiration date, and looks fine. It did rise some, but I couldn’t get it to rise enough. Double checked recipe and everything. Any idea?!
Penny H. July 1, 2018
I don't bake much anymore but the kids do love my scratch biscuits and dumplings. I resent having to purchase new cans of baking soda every time I cook (usually several times a year). The last time I tried to use six month old baking powder my biscuits came out flat, even though I was well within the use-by date. They need to sell smaller quantities for a lower price or figure out how to preserve the product.
Jaye B. April 23, 2019
Yes, smaller containers for things that go bad very quickly!
Nancy H. December 16, 2015
I don't bake all that often and I don't particularly care for the aluminum in baking powder so I make my own with cream of tartar and baking soda. 1tsp baking powder=1/2t cream of tartar +1/4 each baking soda and corn starch. Compose only when you are beginning to bake your recipe. It has no shelf life.
Jaye B. April 23, 2019
Thanks for this great info!
Beehive A. March 9, 2015
Oh my gosh! I have to admit that I had a moment of panic when I first started reading this article.... Baking soda can lose its fizz???? but then I read on and am relieved to learn that I can continue to handle my baking soda in a similarly cavalier way without too much loss in effectiveness. Thanks!!!