What Happens If You Use Expired Baking Soda?

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Baking soda can be found in almost every kitchen — and this has a lot to do with the fact that it might be the most versatile household staple ever. Despite being best known as a cleaning and baking agent, there are at least a dozen unexpected uses for baking soda. However, this odorless, white crystalline powder won't last forever. It is usually good for up to 18 months from the moment it was packaged. Before you toss yours, though, know that this does not mean that expired baking soda is harmful. But let's break this down, shall we? 

Baking soda's shelf life is primarily a measure of its potency. So, technically it does not go bad after its expiration date. It's still very safe to use for an indefinite period of time afterward – so you can rest assured it won't make your homemade brownies unsafe to eat. However, whether it remains as effective as before is a different question. Expired baking soda could make your baked goods a bit flat, because baking soda loses its strength with time. When that happens, it's best to head to the store and buy yourself a fresh new box (or you can even get the Arm & Hammer multi-purpose pack on Amazon). With that in mind, proper storage is crucial to help your baking soda stay effective for as long as possible.

First things first, to properly store baking soda that has already been removed from its box, you need to place it in a sealable container and away from direct exposure to heat and sunlight. You can keep it inside the pantry or anywhere at room temperature between 59 and 77 degrees Fahrenheit. On the other hand, unopened baking soda can be stored in its original packaging, and is best kept inside the fridge or the freezer. However, before you leave the package there, check for tears or cracks. The reason for this is that fridges naturally contain moisture. Every time the refrigerator door is opened, humid air from the room enters inside. Considering that baking soda is highly sensitive to moisture, it can easily absorb it and turn clumpy. 

In case you're suspecting that your baking soda has lost some of its effectiveness, there's a quick trick that can help you find out. The easiest way to test baking soda for freshness is to combine it with an acidic substance, including lemon juice or any type of vinegar for that matter, and see whether it produces carbon dioxide gas. Noticeable fizzing and bubbling indicate that the baking soda is still effective enough to trigger an acid-base reaction. If, on the other hand, there are no visible changes, it's a good indicator that your baking soda has most probably reached the end of its useful life. This is when you might want to consider replacing it. While no longer suitable for baking, expired baking soda can still be used for cleaning.