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At this very moment, serious-minded scientists are hard at work. Some are trying to cure cancer, some are detecting global warming, others are transplanting organs and pumping hearts back to life.

And then there are the guys studying popcorn.

Whether it be increasing the size of an individual piece or eliminating "Old Maids," those annoying unpopped kernels at the bottom of the bowl, researchers from Kutztown to California have focused their efforts on making popcorn just a little bit better for all Americans.

While the Americans who consume 17 billion quarts of popped popcorn a year aren't exactly clamoring for a popcorn revolution, the average man off the street might not object to having his 54 quarts of popcorn a year fluffier and fully popped.

And even if he wouldn't, scientists at Purdue University's Whistler Center for Carbohydrate Research want to know. They have been studying the practical applications of carbohydrates for years, and recently -- or should we say finally -- got around to wondering just how to reduce the number of popcorn kernels that don't pop.

"We just wanted to see whether there is anything at the structural level that can be ascribed to the popping performance," said Rengaswami Chandrasekaran, a professor of structural biochemistry at Purdue University.

The physics of why kernels pop are simple. An outer shell called the pericarp locks moisture inside of the kernel until it is heated, swelling the kernel until the pericarp ruptures. When the kernel pops, the moisture inside is released; the result is the fluffy stuff we call popcorn.

But in some breeds of popcorn, the physics don't work out quite as well. Chandrasekaran and his colleagues studied 14 genetic varieties of popcorn and found that the kernels with the strongest pericarp produce the fewest unpopped kernels.

A kernel with a stronger pericarp can hold moisture better than a kernel with a weaker one, they found. This moisture remains in the kernel as the pressure inside builds with the heat, while in kernels with weaker pericarps, the moisture can leak out, so the pressure will not build up, and the kernel will never pop.

This doesn't have too much relevance to the everyday popcorn eater -- yet. But in a food industry where more is usually better, it might not be long before it does.

"This opens up new avenues to the breeders to breed better popcorn varieties," Chandrasekaran said. "You can do that by natural selection or by genetic engineering."

Not able to genetically engineer your own popcorn? You might ask Paul Quinn if he'll lend you his special popcorn machine to make better popcorn.

Quinn was a graduate student at Lehigh University in 1999 when his adviser, Daniel Hong, started thinking about how to apply physics to everyday things. He published a paper looking at popcorn as a simple model of adiabatic expansion -- similar to the bursting of an overinflated tire.

He and Quinn, along with graduate student Joseph Both, wanted to see if they could make kernels of popcorn even bigger. Hong died of complications from a liver transplant in 2002 and Both moved on to Stanford University, but Quinn, who had already left Lehigh, decided to finish the experiment.

So he built a vacuum popper.

Quinn, now an assistant professor of physics at Kutztown University of Pennsylvania, hooked a vacuum pump into a stovetop pressure cooker, hoping that the decrease in pressure would allow the kernels to expand further than they do in a microwave or in a regular stovetop popper.

To his surprise, the popcorn was almost twice as big as regular popcorn, and had fewer unpopped kernels. He doubled the popcorn's volume.

"The theory is very simple, which is why we didn't think it was going to work," Quinn said.

Although his training is in physics and granular materials, Quinn is continuing work on his special popper, and has applied for a patent on the device. The new apparatus would let the everyday popcorn lover take advantage of the process he discovered, though he's secretive about it for now.

Discover magazine describes it as a contraption with two dog-food bowls and an off-the-shelf microwave. Quinn said results of his testing thus far are promising.

But both Quinn and Chandrasekaran say their work is not just for popcorn eaters. The Carbohydrate Center conducts all sorts of research about starches like popcorn; finding a way to slow the digestion of starches, for instance, might help reduce obesity, Chandrasekaran said.

Quinn doesn't want to have much to do with the food production; he says he just likes the pure physics of popcorn. If he makes money from his new device, then all the better, but he's not expecting much.

"Me, I just like it as a learning tool," he said. "I'll see where it takes me."