Why Does Bread Turn Chewy When You Microwave It?

It has to do with bread's chemical composition

Bread
Lumina/Stocksy United

The microwave is one of the best tools for reheating foods, and it's especially useful in the summertime when you might not want to turn on your oven or stove.

But there are some things that aren't suited for microwave reheating. Bread is at the top of that list. Pizza crust, which is already on the chewy side, becomes downright brittle after only a few minutes in the microwave.

There's a reason for bread's inability to tolerate the microwave, and it has to do with sugar.

Why Bread Breaks Down in the Microwave

Flour consists of protein (called gluten) and starch. Starch is comprised of two sugar molecules. When one of those sugar molecules reaches 212 degrees Fahrenheit, it melts, which softens it.

This is why bread can actually feel soft and fluffy when it first comes out of the microwave. But then when it cools, that molecule recrystallizes and hardens, causing the bread to become chewy and hard.

Reheat Bread and Pizza in the Oven

There are things you can do with pizza that might not work for dinner rolls or that leftover meatball sub.

First, it's worth noting that the best way to reheat bread is to wrap it in foil and put it in an oven set to 350 degrees. For pizza, reheat it on a sheet pan.

But sometimes you don't want to use the oven. Maybe because it's too hot, or maybe you're already using it for something else. So you have to get creative.

Reheating Pizza in a Skillet or Toaster Oven

If you only have a slice or two of pizza, you can heat it up in a cast iron skillet. It works great and retains the crispiness of the bottom crust while melting the cheese and warming up the toppings. Flip the slice over if you want to crisp the top, depending on the toppings.

Of course, a cast-iron skillet takes a long time to heat up, and it stays hot for a long time afterward. So if the goal is to keep your kitchen as cool as possible, you might not want to use cast iron. In that case, try an electric skillet (if you have one).

A toaster oven is great as well, but you can probably only do a slice at a time.

Reheat Your Pizza in the Microwave

You actually can use your microwave to reheat pizza. You just have to be careful to keep the power low and not leave it in there too long.

Set your microwave at 30 to 40 percent power and heat it for 45 seconds. Check the pizza and repeat as necessary. Your bottom crust won't get crispy, obviously, but the cheese will melt (cheese melts at around 120 degrees), and the pizza will warm up without the crust becoming brittle.

Reheat Dinner Rolls in the Slow Cooker

What about dinner rolls? Sometimes it makes sense to bake a bunch of dinner rolls and then freeze them. Or maybe you just have some leftover rolls you want to reheat, or you baked them earlier and want to warm them up.

Wrap the rolls in foil, put them in a slow-cooker with the lid on and heat them on high for about half an hour. They'll be warm and soft when you take them out.