Scientists Discover How Popcorns 'Pop'

Feb 18, 2015 By Radhika
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The act of watching movies has become inextricably linked with the act of eating popcorn!

Whenever I’m in the mood to watch a movie, I throw a bag of popcorn into the microwave for a minute or two. I wait for the popping to cease, open the bag, feel the wave of hot air rush towards my face, and savor the light, crunchy puffs.

But a lot goes into the transformation of the hard kernel in to the fluffy snack.

Two scientists from France analyzed the most striking characteristics of popcorn: the jumping that comes with each explosion and the sound of the popping.

The Process Of A Kernel Popping

The Scientists, Emmanuel Virot and Alexandre Ponomarenko, used high-speed cameras to capture and analyze the steps involved as a kernel pops. They used an oven to heat popcorn, raising the temperature in 10 degrees intervals and recording the kernels as they grew hotter and eventually began popping.

They found that at 100°C, the water in the kernel turns to vapor and splits the hull of the kernel. This release of vapor—and not the action of the kernel jumping into the air—is what causes the sound of the pop.

Gymnastics At Work

The second step happens as the temperature gets higher. The scientists found out that the optimal temperature for popping corn is 180°C, when 96% of kernels burst.

At this temperature, part of the inside emerges from the hull. This piece, called a “leg,” propels the kernel into the air while the rest of the fluffy popcorn continues to grow. This “leg” works just like a leg muscle in a human and allows the kernels to jump.

After all this analysis, the scientists were able to come up with a series of equations—complex ones that involved force, temperature, and pressure—that described the way the kernels jumped as they popped.

While these equations may not be used to solve the more pressing world problems, they could be used to make physics class just a little more interesting.

Courtesy: BBC, NYTimes, others