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Does Brownie Mix Go Bad? Can You Use It After It’s Expired?

Let’s talk about the shelf life and expiration of brownie mix.

Say your brownie mix is already a few months past the printed date but looks perfectly fine. That makes you think: can you use an expired brownie mix?

Or maybe you only needed half of the mix, and the second has been in storage for a couple of months. Now that you’re about to use it, you’re wondering if it’s still any good. Does brownie mix ever go bad or expire?

Sounds familiar?

If so, you’re in the right place. Read on.

Brownie mix box

Table of Contents

Does Brownie Mix Go Bad or Expire?

Brownie mix, if stored in a cool and dry place, doesn’t go bad in the usual meaning of the word. It doesn’t grow mold, start to smell off, or lose its flavor. But if it contains a leavening agent and you store the mix long enough, it will lose some or all of its potency, and your brownie won’t rise properly.

A brownie mix is, at a high level, a combination of sugar, flour, salt, cocoa powder, and a leavening agent. That last ingredient is optional, and if you look at many popular brownie recipes, the ingredients list doesn’t contain a rising agent.

For instance, check out this brownie recipe from Love and Lemons or this one from the Stay at Home Chef.

But if you look at the ingredients list of store-bought mixes, they usually include sodium bicarbonate (also known as baking soda). Here’s one such mix from Duncan Hines.

The lack or presence of the leavening agent is the difference between dense and chewy brownies, and somewhat light and airy ones. No rising agent equals no air pockets in the baked good and, subsequently, dense and fudgy brownies.

(Those qualities are okay for brownies in general. But if the mix should make light and airy brownies, you don’t want flat and chewy ones coming out of the oven.)

I’m pointing that out because the rising agent is the only ingredient that loses potency over time. Flour, sugar, cocoa powder, and salt all last a long time, while baking soda doesn’t.

Now that we have discussed the basics, let’s get to what you’re really interested in.

Brownie mix best-by date
Brownie mix best-by date printed on the label

Can You Use Expired Brownie Mix?

Yes, you can use an expired brownie mix, but you might need to add some baking powder if you want the brownie to be light and airy instead of dense and chewy. If your brownie mix contains a leavening agent, add baking powder to make up for the lost potency.

(We’ll discuss exactly how much you should add in the next section.)

Here’s the thing.

Homemade brownies are typically dense, fudgy, and gooey. Just check out the most popular recipes on Google, and see the photos.

But brownies from premade mixes are, more often than not, relatively light, airy, and slightly similar in texture to cakes. Just see the photos on the boxes.

That means most mixes contain a leavening agent. And that leavening agent will gradually lose its potency some time after the best-by date on the label.

Not sure if your mix contains a leavening agent? Check the ingredients list and look for something along the lines of “leavening agent,” “baking soda,” or “sodium bicarbonate.” Or look at the photo on the label. If the brownie seems quite light and airy, the mix contains a chemical leavener.

So if you want your brownies to resemble the fluffy and airy ones pictured on the box, you need to add some baking powder that will take care of leavening the baked good.

(In theory, you could use baking soda instead, as brownies typically have enough acidity to activate it, but things are simpler when working with baking powder.)

Now, the only question is how much baking powder to add to your mix. Let’s discuss that.

Making brownie batter

How to Revive Expired Brownie Mix

If your brownie mix doesn’t contain a leavening agent, you can use it as-is months or even years past its date. But if it does, add a teaspoon of baking powder per two cups of the mix to revive it. If the mix is “expired” for less than half a year, halve that to one teaspoon per four cups.

That’s a very rough estimate of how much baking powder you need.

In my article on expired cake mix, I discuss how I came up with a ratio of one teaspoon of baking powder per one cup of cake mix. And since brownies shouldn’t rise that high and be so airy, I suggest halving that amount.

Here’s the rationale.

The brownies you get when following the recipe from a brownie mix aren’t as light and airy as cakes tend to be. So to achieve that texture, you probably need to use about half of the amount of baking powder.

Of course, you might decide to add a bit less to get a batch of brownies that are even flatter, if that’s your thing.

Use your expired brownie mix for some low-stakes weekend baking, not when making brownies to impress someone with your baking skills. I can’t guarantee that adding the mentioned amount of baking powder will make the brownies come out exactly the way they’re supposed to.

Now, if your brownie mix has just “expired” or is a month or two past its date, I suggest you use it as is without any extra baking powder. The leavening agent should still do its thing, and the baked good should rise nice and tall. The worse that could happen is slightly less airy brownies.

But if it’s more than those two months beyond the best-by date, an eight up to a quarter teaspoon per cup should help. And if it’s more than half a year expired, add half a teaspoon per cup.

Finally, let me remind you that you should only add that extra baking powder if your brownie mix contains a leavening agent. If it doesn’t and is supposed to produce flat and fudgy brownies, use it without any extras.

Unfortunately, there’s no good way to check if the leavening agent in your brownie mix is still active. You have to bake the brownie to see for yourself. When dealing with an expired pancake mix, you can make the batter and cook a single pancake to see if it’s flat or fluffy. And if the former is the case, you add the required baking powder and continue cooking.

How Long Does Brownie Mix Last?

Brownie mix has a shelf life of about a year.

If it contains a leavening agent, which is quite common, it should retain potency for a couple of months past its date. But if it doesn’t, it’ll stay fine to use for months, if not years, beyond the printed date.

Unfortunately, there’s no good way to tell how long after the printed date the mix containing a leavener will stay potent. Because of that, if it’s more than two months past its date, I suggest adding extra baking powder to ensure you get some rise.

To learn how much you should add, read the section on reviving expired brownie mix.

Once you bake them, brownies last for about 3 to 4 days at room temperature or up to 6 days in the fridge.

How to Store Brownie Mix

Keep your brownie mix in a cool (70°F or below) and dry place, away from sunlight, and sealed tightly. If you don’t use the whole bag in one go, transfer the leftovers to an airtight container or a freezer bag. Or at least seal the original bag using a plastic clip.

That’s about all it needs.

As long as your brownie mix is well sealed, it should last a long time.

A good seal keeps your brownie mix away from moisture, ensuring it cannot absorb any and grow mold. Plus, it keeps any pantry bugs at bay.

Brownie mix sealed airtight
Airtight seal guarantees a long shelf life

You can refrigerate or freeze your brownie mix, which might be beneficial, as it’ll help cocoa powder retain quality for longer.

That said, cold temperatures aren’t as helpful as they are when storing, say, full-fat powdered milk, which lasts longer if refrigerated.

Next, let’s discuss when you should discard your brownie mix instead of trying to revive and use it.

How to Tell if Brownie Mix Is Bad?

Discard your brownie mix if:

  • There are pantry bugs inside. If your mix is infested, it’s done for. Toss the bag and examine nearby products to ensure they aren’t infested too. Pantry pests things spread like wildfire.
  • The mix is moldy or has wet clumps. Small dry clumps are normal, and you can break them up using a sieve or a fork. But if the lumps are wet or there’s mold, it’s a sign that moisture got to the powder. And if that’s the case, it’s best to discard the whole thing.
  • It’s too old. While you can surely use an expired brownie mix, at some point, enough is enough. Unfortunately, I can’t tell you how long is “enough” for you because it’s a matter of personal preference. But for me, if the mix is more than two years past its date, I discard it.
  • It smells weird. An off smell isn’t common for brownie mixes, but if yours give off a strange odor, don’t use it.

Those are the typical signs of brownie mix being spoiled. But if there’s anything else about yours that doesn’t feel right, get rid of the mix. Better safe than sorry.

Brownie Mix Shelf Life and Expiration Summary

Thanks for reading this short guide on brownie mix. Here are the key takeaways:

  • Homemade brownies are usually chewy and fudgy, while ones made from premade mixes are slightly lighter, airier, and a bit cake-like in texture. You achieve that texture by adding a leavener to the mix, the same way it’s done in cake mix.
  • Brownie mix doesn’t go bad in the traditional meaning of the word. But if it contains a leavener such as baking soda or baking powder, it won’t stay potent forever. At some point, the leavener will lose potency, and the resulting brownies will be super dense and chewy.
  • If your brownie mix doesn’t contain a leavener, you can use it as-is for months or even years past its date. But if it does and is more than two months expired, stir in a 1/4 teaspoon of baking powder per cup to revive it. If it’s more than half a year expired, double that to half a teaspoon per cup.
  • Store brownie mix in a cool and dry place, sealed tightly. Refrigeration and freezing might help a bit but aren’t necessary.