Does Popcorn Ever Go Bad?

This classic movie snack might be a mainstay at theaters, but it actually doesn’t last forever.

Like all great things, this classic snack doesn't last forever.
Like all great things, this classic snack doesn't last forever. / Paul Taylor, Stone Collection, Getty Images; Justin Dodd, Mental Floss (background)

Popcorn is a pretty wild kind of treat if you think about it. It’s a snack created in an explosion of sorts, and it’s culturally tied to the movies, where you can watch other explosions on enormous screens. People have been enjoying it for at least a thousand years; popped kernels have been found in both Peru and Utah dating back that far.

But does it ever go bad? Yes, it can. So, we are going to break down all of the difference between popped and unpopped kernels.

Can You Tell When Kernels Go Bad?

Kernels that haven’t been popped are usually more robust, with that thick husk protecting the fats and oils inside from exposure to the outside world. There’s a limit to how long they can do this, though, and that limit is generally between one to two years.

Over that time, kernels tend to lose their moisture and become less likely to pop when you want them to, as their popping comes from the water in their outer layer once they’ve been heated up to the point of explosion. 

Tell-Tale Signs Your Popcorn Has Expired

You can tell when popcorn’s past its prime once you bite into it, and it feels more like eating packing material than snacking on actual food fit for human consumption. But there’s a difference between “off-puttingly soft” and genuinely spoiled. And popcorn can hit its expiration date whether it’s in unpopped or popped form.

Popcorn that has extra stuff on it—caramel, nuts, even just butter—has more opportunities to go bad. No matter the topping, it all creates additional opportunities for bacteria, mold, and other micro-hideousness to thrive, so be sure to look it over before you take a nibble.

That being said, eating microwave popcorn that has technically expired is unlikely to do you any serious harm. The odds are it just won’t pop very well; if it does, it might seem a bit dry and soft. Bad popcorn, essentially.

How Long Does Leftover Popcorn Last For?

But what about popcorn that has already been popped? Typically, that can last for up to two weeks but is only likely to do so if stored well in an airtight container. Realistically, it starts to taste a little crappy after a few days. Again, though, popcorn tends to go stale rather than properly spoil.

That said, mold and odor issues can take root anywhere food is, so if anything smells funny or has changed color, you might be better off tossing that leftover popcorn in the trash than your mouth. It’s not likely to be particularly tasty by that point, anyway.

However, if your popcorn is just soft and stale, you can always try reviving it by popping it in the oven for a few minutes. You can even repurpose those leftover bits into popcorn balls or even croutons.  

All in all, the best thing to do is stick to only buying as much popcorn as you’re ready to consume, then eat it all pretty swiftly. Ideally, while it’s still warm and dripping in butter, and as muscular dudes blow things up and make witty one-liners on as large a screen as possible. 

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