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CINEMA audiences could be in for an extra-special treat—giant popcorn.
Physicists in Pennsylvania have cooked up a mathematical recipe for a fatter and
fluffier snack, which could also save manufacturers and consumers money.

Daniel Hong at Lehigh University in Bethlehem, Pennsylvania, devised the
recipe after hearing a speech by Young Hwa Kim, head of a company that applies
physics to industrial problems. Kim mentioned one challenge that a food company
had raised: how can you double or triple the size of popcorn?

To find out, Hong and his graduate student Joseph Both tailored some standard
equations of thermodynamics to describe how popcorn pops. When corn is heated in
a pan or cooker, water inside the corn’s hard shell turns into steam. Eventually
the steam pressure becomes high enough to rupture the shell: the fluffy inside
then bursts out to equalise the pressure.

Hong’s maths showed that there is a simple way to make a bigger snack: to
give popcorn x times as much volume, simply reduce the pressure in the
cooker by a factor x1.3. “So if I want to make it 10 times larger, I
need to reduce the pressure about 20 times,” he says.

Such pressure drops would be easy for industry to achieve. Hong has submitted
his work to the journal Physical Review E, and plans to experiment with
corn in a vacuum chamber to see how big he can make popcorn in practice.

“If industry is interested, I’d be willing to work with them,” he says. “Big
popcorn would be more fluffy, and perhaps easier to eat,” he speculates, adding
that it could save industry and consumers money. “If the popcorn is 10 times
larger, then you’re selling just a tenth of the amount.”