MillerCoors, last year, introduced punch-top Miller Lite beer cans that require the drinker to pull the tab, then punch a second hole it the can's top, resulting in smoother pours. Ingenious, right? But punching a second hole into beer can lids is hardly revolutionary.
From 1935 until the pull-tab beer can was invented in 1962, beer came in flat-top or cone-top cans. Flat tops required a can opener to open. When doing so, many opted to punch one large hole for pouring, and a second to allow air to get in.
TV ads for “Silver Bullet” cans this year boast “double-vented wide-mouth” technology, featuring scientists in lab coats who explain how it works, as if we needed to know.
To learn more about why extra beer can holes make a difference, University at Buffalo professor and physics department chair
Huong Luo - a scientist by trade –talked about the space in a hole unoccupied by liquid as it pours from a hole. Air is sucked into that space.
“There’s a counter flow; as liquid comes out and air goes in,” Luo said. “The air is also responsible for the noise you hear, like a gurgling, when a liquid is poured.”
The extra hole, he said, prevents the counter flow and makes for a smooth pour.
“It’s a continuous, smooth flow,” Luo said.
This is also why on gasoline cans, there’s a small vent which, when open, lets air in. It helps control the pour and results in less gas splashing around.
Although Luo didn’t conduct his own beer-pouring experiment, he said a second beer can hole should result in a smoother pour. It also may mean less foam and a smaller head on the beer, which puzzles him.
“You may have less foam, but I thought that’s what people enjoy having,” he said. Now there’s a thought: Do people want heads on their beer or not?
Give it time.
Instructions from MillerCoors are probably on their way any minute now.