Beer cans, once the vessels of crap beer only, have recently been embraced by craft brewers nationwide. It's a beer can renaissance! But despite the surge in popularity, beer cans aren't perfect. Invert the can too quickly and you're going to get a very uneven pour and a mouthful of air. But this simple hack, known as the Shark Fin, vents the beer can, resulting in a smooth, consistent pour from beginning to end. You might think of it as a gentleman's shotgun.
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How To Do It
It really couldn't be easier. Just be careful you don't poke yourself with any sharp edges.
- 1. Open your beer can as usual.
- 2. Pull the tab off of the beer can. It should just take some light prying.
- 3. Bend the tab back and forth until the upper loop breaks off. You should be left with the bulk of the tab, which will have two sharp corners. You can discard the upper loop.
- 4. Force one corner of the broken tab into the upper side wall of the beer. You want to place it on the opposite side of the mouth. Make your puncture right near the very top of the beer; too low and beer will start flowing out. If you're having trouble piercing the can's wall, try scoring it a couple times, then slowly, forcing it through. You want to penetrate deeply enough so that most of that sharp corner goes in, right up to the other sharp corner. If you do it right, you should be left with what looks like a shark's fin sticking out of the water.
- 5. Drink your beer.
You should find noticeably improved air-flow in your beer. It shouldn't come bubbling and lurching forward, but gently flow forth in a placid stream of deliciousness.
How It Works
The Shark Fin draws its power from the magical worlds of fluid dynamics, gravity, and how the two interact. Gravity, of course, wants to pull the beer downward and out of the can. But if the liquid poured out of the container and nothing could replace it (i.e. it was a perfect seal and magically no air could get in) the can would collapse in on itself because the atmospheric pressure of the air outside the can would be greater than the vacuum created inside the can.
This, of course, does not happen with a can of beer, but that's what wants to happen. As the liquid pulls down, the walls of the can are pulled inward. However, the weight of the beer (12 to 22 ounces, typically) is not enough to create the force needed to collapse the can. If the beer were somehow able to form a perfect seal at the can's opening, the fluid would be held in place. Again, this doesn't happen with beer cans in real life—the opening is too big and the fluid is too thin to create the right combination of pressure and surface tension—but that's what it's trying to do.
Instead, what actually happens is that air comes in through the same hole that the fluid is pouring out of. This relieves the pressure inside the can, and allows the fluid to escape. The problem is that this creates a traffic jam, with liquid flowing one way (downward) and air flowing the other way (upward) through the same hole. Imagine a bunch of commuters at rush hour, coming from two different directions, trying to pass through the doorway. Traffic passes both ways in fits and starts. It's the same with a beer can. A burst of beer spills forth, a big bubble of air goes in, another mouthful pours out. It's chaos in your mouth.
The Shark Fin is order. It is calm. It is, in short, a vent. Essentially the Shark Fin gives air its own doorway for getting into the can and balancing that pressure. It's like taking a two-way street that was only one-lane wide and re-routing one direction of traffic so they each have their own street. Now the beer can pour out in a steady stream, and it doesn't have to fight against the opposing force of air rushing in.
Isn't That Just a Shotgun?
It's very similar, but they each have different use cases. The shotgun is for one thing and one thing only: pounding a can of beer. You jab the side of the beer (toward the bottom) with a key, carve out a mouth-sized hole, put it to your lips, and then pop the top on the beer. In this case it's the can's top which actually serves as the vent; because air is coming in from the opposite side, it allows you to completely invert the beer and air comes right in from the top, unopposed, shoving the liquid directly into your mouth with hellacious speed.
The disadvantages to the shotgun are obvious, though:
- 1. It's messy.
- 2. You could cut your lip on the opening you carve, if you're not careful.
- 3. Once you start a shotgun, you have to drink the whole beer. You can't put it down.
All of which means shotgunning is great, but it's not for casual drinkers. It's for pounding. Wonderful for bros, but even bros need a break sometimes.
The Shark Fin, on the other hand, provides the same improved flow but without the mess. If you do it right, there will be no spillage at all. It's very inconspicuous, and even if someone did see it, it actually looks kind of cool. It's sort of a conversation-starter. And perhaps most importantly, you can continue to drink your beer casually, sipping as you go, for however long you like. You can drink faster, too, if you want, just not as fast as if you were shotgunning.
We're Going to Need a Bigger Liver
Despite all its advantages, the Shark Fin isn't nearly as well-known as the shotgun. The concept is catching on to some extent, though. Last year, Miller introduced a Punch Top can that does basically the same thing, and in June of this year Molson followed suit. The Shark fFn, however, gives you the advantages of the same venting, without the disadvantages of drinking Miller or Molson (namely, you have to drink Miller or Molson).