Field Notes Extra · Hold My Beer

Last week, we tested an old bit of barroom wisdom: tapping a shaken can of beer before opening it will keep the beer from ending up on the ceiling.

The beer had opinions.

So did the Internet.

Several readers and viewers pointed out that we had, apparently, been tapping our beer incorrectly. We needed to tap harder. We needed to tap closer to the opening. We needed to tap gently around the sides to “dislodge the carbonic acid.”

And, according to one particularly helpful correspondent, we needed to stop tapping it “like a pansy.”

Fair enough.

We said, Hold my beer.

We went back into the Applied Fizzics Laboratory, shook two more cans, started a stopwatch, and tried it your way.

And then, because we still weren't satisfied, we did something you can't do with an aluminum can:

We looked inside. Watch the video below.

What we found was more interesting than simply whether tapping “works.” Beer contains proteins and other compounds that help stabilize its foam, allowing bubbles to persist surprisingly long after shaking.

And then we tried the same experiment with soda.

That raised another question entirely.

More soon.

We'll be back next week with Field Notes #9, on fermentation and the origins of CO₂ in beverages.

Cheers,