Commercial baking soda and baking powder will last for quite a long time on your cupboard shelf, but they will eventually lose their potency and expire. If you're wondering if yours is still good, it's best find out with a quick test before baking rather when your muffins emerge from the oven dense and flat. Here's how!
For baking powder, all you have to do is stir about 1/4 teaspoon of powder into 1/2 cup or so of very hot water. Tap water is fine, and the proportions aren't fussy. The soda will immediately start to bubble if it's still good.
Baking soda needs an acid to get a reaction, so use the same method as for baking powder but add 1/4 teaspoon of vinegar to the water before water before adding the soda. As before, if it bubbles up, your soda is fine to use.
If you don't see bubbles, then sadly, you'll need to take a trip to the store and buy a fresh box! If there isn't much fizzing, your ingredients are likely on their way out. You can probably still use them to get some lift, but your baked goods will be more dense that usual. Don't be tempted to double the amount of baking soda or powder - that would make your food taste seriously strange!
Related: Fighting Odors: Do You Keep Baking Soda in Your Fridge?
(Image: Flickr member Mel B. licensed under Creative Commons)
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Ack, I could have used this post last week.... I didn't even think about trying to test my baking powder. It was over 2 years old and I was starting to suspect it was losing it's potency. O well, it didn't hurt to just go ahead and get a new one....
How long is "quite a long time"? I've had my baking soda for.. I don't even know how long, it's been so long! I'll do the test when I get home either way - I assume any vinegar will work? I don't think I have white vinegar, but I do have cider..
I never understand what is the difference between baking powder and
Baking soda..!
how does baking soda get old? I never have any hang around my house for longer than a couple of weeks! If I'm not baking with it, I'm using it to clean with, or brushing my teeth with it.. or drinking a tsp of it in a glass of water to cure heartburn..
@ AlisonCJ - Baking powder has a shelf-life of 9-12 months. We were taught in culinary school that baking soda is shelf-stable if it's kept at room temperature (and doesn't expire), but the box has an expiration date that's usually about 3-4 years from the date of purchase. I tend to think it's a good idea to switch the soda out around then!
@Patyy - check out these posts:
What's the Difference between Bakign Powder and Soda
Baking Powder and Soda: Why Use Both?
According to Arm and Hammer they tell you to pitch your baking soda after 3 months of opening but yea right. Just as EmmaC said, it's pretty much got an indefinite shelf life but if its getting up in the years, spring for a new box.
Thanks for the informational post on the diff. between soda and powder!!!!!
Even if you discover your baking soda has gotten too old to bake with, you can still keep it around for cleaning purposes!
I think baking soda pretty much never goes bad, but it can absorb off odors if it's been sitting around for a long time. If it does, I don't think I would bake with it but I would still use it for cleaning.
Yeah. Basic high school chem FTW.
In answer to your question, I do keep baking soda in my fridge and freezer. I also keep a box in the bathroom to help absorb odors there. Another spot where I have a container of baking soda is right by the stove, in case of grease fire.
While you're at it, you can pour your vinegar/baking soda down the plughole. I find this really good for freshening things up down there!
I was unaware that baking soda could even expire, this is news to me. That is an easy test to see if it's still good, as some of us have baking soda lying around for long periods of time.
America's Test Kitchen did a test on this, and took two baking powders, one fresh, and one older than 6 months, and both passed the hot water test, but the older one didn't have the same lift when making biscuits, so they're conclusion - toss it after 6 months
It's among the cheapest ingredients in any recipe you are likely to make and with the potential to ruin more expensive ingredients-- why not replace it every six months?!
Good to know! Thanks for posting!
Making biscuits tomorrow and was wondering about my baking powder, thinking it must be two years old. After reading this - I did the test and it bubbled and fizzled just fine. Then I read the expiration date...August 2000 - Rumford - 12 years and still going strong! Goes to my theory that expiration dates are merely suggestions.
Never throw away baking soda. Throw a cup or so in your washer to soften the water and make the laundry detergent work more efficiently. I buy the huge box of baking soda for just that purpose and keep a smaller amount in an air tight storage container in my pantry.