May 27, 2011
Science in the Public Interest: The Beer Koozie Test
With the official kick-off of outdoor barbecue season this weekend also comes an alarming increase in beer waste. According to the Bureau of Bogus Statistics I Totally Just Made Up, as much as a third of every beer opened during the summer months goes unconsumed. The primary reason: the beer has gotten warm. When the mercury climbs, canned and bottled beverages don’t stand a chance of remaining palatably cold to the finish. With sodas or mixed drinks, it’s no big deal—just add ice. But beer doesn’t taste good with ice (even, in my opinion, when “ice” is just in the name).
Some people might say, “I don’t have that problem. I drink my beer in one long guzzle so it never has a chance to get warm.” Those people might have problems beyond warm beer.
For the rest of us, some marketing genius out there invented the koozie. The koozie, in case you are unfamiliar with the term, is a little foam insulating sleeve that fits around an aluminum can or, in more recent versions, a bottle. No one seems to know the origin of the name (or of the product itself, which became popular sometime in the 1980s), but my best guess is that it is a corruption of the word “cozy”—as in a tea cozy, meant to keep the teapot warm—with an extra “o” so it sounds like “cool.” Switching the “c” to a “k” must have been a byproduct of the era when bastardized spellings and superfluous umlauts were considered cool (see “Mötley Crüe”).
Whatever the origin, the koozie has several undeniable benefits: It keeps your hand from getting cold and covered in condensation. It’s a good way to identify one’s beer at a party, where it could easily be confused with look-alikes—the second most common cause of beer waste, according to the BBSITJMU. It can be used as camouflage: a friend of mine who was pregnant, but not ready to reveal her status to friends, covered her nonalcoholic beer in a koozie to avoid arousing suspicion. Finally, it’s a personal billboard, allowing you to proclaim your allegiance to a sports team; declare important sentiments, like that you’re “not as think as you drunk I am”; or go formal with a tuxedo koozie. You can even support independent crafters by buying felted, crocheted or cowhide koozies on Etsy.com.
But how well do they actually work at keeping your beverage cold? In the interest of preventing beer waste, I put them to the test. Recently, my husband and I conducted an experiment with three bottles of beer: I held one in a koozie, my husband held one without, and a third one, also koozieless, was set down between sips. We drank them at the same rate, alternating between the two held beers and the third beer, stopping at five-minute intervals to evaluate the temperature. The air temperature was 67 degrees Fahrenheit (not exactly sweltering, but it was early evening).
Within five minutes, there was already a subtle but noticeable difference between the beers we were holding—with koozie and without—and the unhandled one. The latter was still frosty, while the others had already started to lose their chill. The gap widened over the next ten minutes. At 15 minutes, the one without the koozie was warmer than the one with, but the unhandled beer was still coldest. Finally, at the 20-minute mark, all three were less than refreshing, but the one that had been held least remained coolest.
Our conclusion: the koozie helped, but not as much as limiting the beer’s time in hand.
Would the results have been different if we were using cans? If the air temperature had been warmer (especially if it had been warmer than human body temperature)? If we had a beer in a koozie that we set down between sips?
Hard to say. If any science-minded beer drinkers out there care to conduct their own experiments, be sure to let us know the results.
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So I guess we should all not pick it up and drink it with a straw…I’M FOR THAT!!!!
nice choice of beer! Lake Placid IPA ROCKS!
When I lived in Australia, many of my friends or their Dad’s brewed their own beer at home (beer prices are much higher in OZ), So they always had a cold one ready to offer and they could proudly say they made it themselves. It become their hobby. Many people wonder how to homebrew and a lot of people either think that if they home brew their own beer, it will either be expensive, taste Disgusting or, be Really Difficult to Do. And to be honest, that’s what we thought many moons ago before we started to homebrew our own beer. http://bars-and-bartending.com/how-to-homebrew.html has all the directions, ingredients and supplies.
I, for one, appreciate your sacrifice for the greater good…thanks for drinking beer for us!
Good to know koozies do their job, but surprised it’s not as much as expected. There are many different kinds of koozies (stainless steel koozies, neoprene koozies, etc.) and I suspect some do a better job than others. Perhaps some other time your tests could include more than just one type of koozie? Otherwise, good job and thanks for the good info!
From my own personal experience nothing beats a thermos!
I recently saw someone using a coffee mug as a can koozie, still wondering how effective that would be?
For the opposite effect I thought these were neat to heat your coffee: http://www.kickstarter.com/projects/705847536/coffee-joulies-your-coffee-just-right
Now that is a result I would not have expected! Just let the bad boy sit there and it stays cooler. I am a golfer, so have to select the slim koozies vs the original fat ones so that they fit in most golf cart holes. But, since I am golfing, I get the benefits of both not holding the beer and having a koozie around it. Secondly, I golf year round, so during the cooler months, I get the third benefit of cooler adjacent air.
It depends on the material the koozie was made out of; Specifically the liner used inside. If it was Neoprene it would hold the drink coldest for the longest period vs foam liner.