We all know the beer tappers. The people who — no matter whether a can was recently shaken or has been sitting sedentary in the fridge for weeks — flick the can a few times to make sure it doesn’t fizz over upon opening. But does that little nail tap actually do anything?
As we approach the 85th anniversary of the beer can, we finally have an answer. Researchers at the University of Southern Denmark tested the theory, putting “1,000 cans of lager” through randomized controlled trials, according to the MIT Technology Review, to determine whether or not tapping has any effect on beer loss from foam, fizz and other spraying.
But first, MIT Technology Review sets up the hypothesis:
“There are good theoretical reasons to think this should work. The tapping should release any bubbles that are stuck to the inside walls of the can. These should then float to the surface and dissipate, making the beer less likely to foam when it is opened.”
This experiment was particularly suited to the Danish researchers because biking is particularly popular in the country, and subsequently so is showing up to a party with a six-pack that’s been jostling around in a backpack across all manner of bumps, curves and curbs. According to the study, the team’s can-shaking method “successfully mimicked carrying beer on a bicycle for 10 minutes – a common way of transporting beer in Denmark.”
What were the results? Is it a point for the beer tappers or the devil-may-care crispy boy crackers? Here’s what the research team had to say:
“These findings suggest that tapping shaken beer cans does not prevent beer loss when the container is opened. Thus, the practice of tapping a beer prior to opening is unsupported. The only apparent remedy to avoid liquid loss is to wait for bubbles to settle before opening the can.”
That’s right. Tapping the can does absolutely nothing — nothing! Well, at least according to this one experiment. But hey, they only tapped three times in the test. Maybe you need to tap four times.
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