What Happens When You Ignore the 'This Side Up' on Microwave Popcorn Bags

If you're like me and prefer to stick to the instructions, seeing the 'This Side Up' warning on a microwave popcorn bag feels like a serious reminder: mess this up, and there will be consequences.

I always figured the 'This Side Up' instruction was there to prevent disaster—like burnt popcorn, unpopped kernels, or even a potential microwave meltdown. But I've just accepted the mystery and trusted the process.

But, since it's my job to tackle the kitchen questions that others avoid, I decided to try popping a bag with the 'This Side Down' and survive to tell the tale. Here’s what happens when you break the popcorn rules.

Honestly, not much at all.

Here’s why: Microwave popcorn bags have a designated side to be placed up because one side contains a susceptor. This special material absorbs microwave energy, converting it into heat, which accelerates the popping process and ensures the kernels expand into fluffy popcorn.

Popcorn can pop without a susceptor. You could toss some kernels into a plain paper bag, and they’ll still turn into a tasty treat in a few minutes. However, a susceptor helps ensure more kernels pop fully, and fewer unpopped ones remain, giving you better value for your money.

When I popped the bag with the susceptor on top (the wrong side), it took a few extra seconds for the kernels to start popping. The bag was less full when finished compared to the one with the susceptor on the bottom. Plus, the upside-down bag didn’t reach the usual steady popping rhythm; it sounded a bit more chaotic, though it still popped enough kernels for a snack.

You’ve likely seen a susceptor in other microwave products like pizzas or Hot Pockets. These 'crisping sleeves' focus microwave energy to heat thicker parts of the food more quickly.

In the 1990s, scientists began questioning the safety of these heating devices. The FDA raised concerns that the energy-absorbing capabilities of the susceptor might create harmful chemicals from other packaging materials, such as adhesives or paper.

In the end, food safety regulators issued a set of guidelines to address concerns about the use of susceptors, making it safer for their intended purposes. As a result, susceptors are still found in products ranging from microwave popcorn to frozen fish sticks.

If you realize halfway through that your popcorn bag is upside down, don't worry! Your snack is still on track. You can either stop and flip the bag, or just let it be. There might be fewer fully popped kernels, but the difference is minor, and you'll still get plenty to eat.

Keep Popping!

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