Why Rice Krispies Go Snap, Crackle, Pop!

Why Rice Krispies Go Snap, Crackle, Pop!

There’s a bumper sticker out there that reads, “I do whatever my Rice Krispies tell me to.” Before taking orders, you might want to consider that no one really knows how the crispy cereal gets its commanding voice.

In fact, we may never understand the full story behind the snap, crackle, and pop, because finding money for experiments on cereal noises isn’t easy.

”I have not seen anyone fund this,” said food scientist Ted Labuza of the University of Minnesota. “It’s not rocket science.”

However, over the years Labuza and other cereal scientists have come up with some pretty good suggestions to explain where the noises come from.

Shattered glass

A Rice Krispie behaves like a piece of glass. If you hit it hard, it’ll break into a puzzle of a million pieces that, if you had the patience, you could put back together again.

The high temperature at which the cereal’s cooked creates extremely strong bonds that hold the rice’s starch molecules together. The strong bonds make the rice act like glass.

During the cooking process, each piece of rice expands and a network of air-filled caves and tunnels form inside.

Under pressure

When you pour milk into your breakfast bowl, the cereal absorbs the milk. As milk flows into the crispy kernel, the liquid puts pressure on the air inside and pushes it around.

The air shoves against each pocket’s walls until they shatter, forcing out a snap, or a crackle, or, as you, know, sometimes a pop.

You can also see tiny air bubbles escaping to the surface.

The race is now on. Because once the rice is wet enough, all the air pockets have burst, the sounds stop, and you're left in peace and quiet to eat soggy cereal.

Corey Binns lives in Northern California and writes about science, health, parenting, and social change. In addition to writing for Live Science, she's contributed to publications including Popular Science, TODAY.com, Scholastic, and the Stanford Social Innovation Review as well as others. She's also produced stories for NPR’s Science Friday and Sundance Channel. She studied biology at Brown University and earned a Master's degree in science journalism from NYU. The Association of Health Care Journalists named her a Centers for Disease Control and Prevention Health Journalism Fellow in 2009. She has chased tornadoes and lived to tell the tale.