'Stein of science' keeps beer cold for days

SAN FRANCISCO — Ask Phil Broughton if he's ever dismantled a nuclear bomb, and he'll pause, clasp his hands around his thick red beard and give a couched answer.

"Not that I can talk too much about," said Broughton, a radiation safety specialist at the University of California, Berkeley.

What he does want to discuss is beer: specifically, a stein crafted from lab equipment normally used to keep liquid nitrogen so cold it doesn't boil off into vapor. Beer will stay perfectly frosty for days if left alone in the vessel, he says. That discovery has turned into a business for the 34-year-old, who began selling high-tech mugs for as much as $375 last year.

"The primary buyers have been coming out of academic and research institutions, but by no means are limited to that," Broughton said. "I've had bankers, lawyers, architects, IT folks and, in one case, a Coast Guard lieutenant."

He first realized he had something valuable while celebrating Oktoberfest at a bar in Ben Lomond, Calif. He poured a pitcher of beer into one of his steins, keeping it cold for hours. The bar owner told him he could get hundreds of dollars for his invention, showing him a hand-carved German stein that cost $3,000.

He decided to fashion his first "stein of science" in September, during one of his furlough days.

The steins are made from a piece of lab equipment known as a Dewar flask. It was invented more than a century ago by James Dewar, a Scottish chemist and physicist who was the first person to produce hydrogen in liquid form. Dewar didn't patent his invention and lost out on a commercial opportunity when a German company called Thermos started manufacturing a similar product in 1904.

Broughton's steins are made with more precision than a typical thermos. That means liquid, whether beer, coffee or tea, will retain its temperature much longer. Empty, they weigh between half a pound and 5 pounds.

Langford, 33, likes to show off the stein's effectiveness by pouring piping hot coffee in it in the morning, then removing the cap six hours later to see steam rise out of the cup.