A new research published in the Journal of the Royal Society Interface on Tuesday reveals the baffling mystery revolving around popcorn popping, offering the perfect solution to a perfect state of the all so popular snack. The thermodynamic analysis along with high-speed imaging techniques were used by French engineers Alexandre Ponomarenko and Emmanuel Virot in order to find out the ideal temperature for maximum popping and the mechanics behind the popcorn’s jumping, as well as the origin of the well known sound popcorn makes whenever a piece is ready for consumption.
They used a high-speed camera and took 2,900 pictures every second of this unexplored physical phenomena. Prior to this discovery, they had trained their shooting technique using it on plants.
“So far, there have only been commercial studies on popcorn, so we were eager to look at the phenomenon scientifically,”
Emmanuel Virot of the Ècole Polytechnique in Paris, said.
It appears that the sound that make is caused by a sudden escape of water that is evaporating when the cooking temperature reaches 356 degrees Fahrenheit. That’ s why whenever they are cooked at less than 356 degrees, 60% of the kernels remain un-popped.
The 2 engineers linked the popping sound to the exact moment at which the water vapor inside the corn kernel is so hot that it forces open the surrounding shell.
Because a starch leg is forming at the bottom of every emerging popcorn in order to make that jump possible, by doing one-and-a-half somersaults, the kernel is thus transformed into the shape of popcorn as we know it. Virot and Ponomarenko proved the jump resembles the somersault of a running gymnast. Using their high-speed camera, they analysed both the fracture as well as the expansion of one piece of popcorn resting on a hot plate. As the hull is breaking open and the starch flake is expanding, it forms a what they called a single “leg.”
Next, Virot and Ponomarenko put microphones to the hot-plate so as to identify the source of the popping sound and found that it didn’t correspond neither with the cracking of the hull nor with the flake’s falling back against the plate. Instead, the sound is made by the pressure drop inside the kernel, thus turning the flake into an “acoustic resonator.” The same thing happens to a champagne bottle as it pops whenever it is opened.