Those of us drinking-age adults who choose to partake do so in different ways. Whether you’re a drinker who prefers the symphonic flavor depth of wine, a no-nonsense type who likes the two-fisted fire of straight spirits, or an enormous craft beer dork who writes for The Takeout dot com, we all have different stories.
Except for one. There’s one story that seemingly everyone has heard, internalized, and repeated. And it’s entirely fictional. I’ve heard dozens of slight variations, but they all come down to this: Don’t let cold beer get warm and then re-chill it. It skunks the beer.
Your cool RAs, fun uncles, and party roommates were all wrong. And yet, the myth persists. I hear it repeated, basically the same way, very frequently from customers at the brewery where I work. This is the closest thing to ancestral pagan beliefs we have in the beer industry. Let’s take a look at what’s going on.
If we’re going to accept the idea that the cold-to-warm-to-cold transition “skunks” beer (more on the scare quotes soon), then you have to wipe out all beer stored at shelf temperature in groceries, liquor stores, and bottle shops. Beer is packaged cold, in large part because carbon dioxide stays in solution much better in cold liquid than warm. So even the warm beer you insist on buying over the stuff in the cooler, so as not to skunk it, was cold once already.
But let’s get someone with a degree that didn’t involve writing papers about The Canterbury Tales in here. Allison Lange is the R+D Molecular Bioloigst at the well-respected Omega Yeast Labs in Chicago. And while she’s not sure where this cold beer myth got started (no one is, though there are some fun anecdotes in a Twitter thread about this), she can definitively declare it bunk.
“Buying cold beer, letting it come to room temperature for a few days, then re-refrigerating your beer will have no significant ill effects on the flavor or life span of your beer,” Lange said.
There you have it, from an actual beer scientist.
We’re also running into a language issue here. Most people consider “skunky” to mean “there’s something wrong with this beer” and/or “I don’t like it.” I know I used it that way for years. But there’s a reason we call it specifically “skunky.” A skunk reason!
“‘Skunked’ beer is caused by exposure of beer to light and has nothing to do with storage temperature,” Lange said. “The characteristic sulfury, skunky aroma appears after bitterness molecules in beer called iso-alpha acids get hit with UV light and break down almost instantly into several compounds including 3-methyl-2-butene-1-thiol (MBT), which is chemically similar to the compounds that skunks make that give them their distinctive smell.”
This means that your canned and kegged beers will literally never come to you skunky. Green bottles offer some UV protection, and brown bottles offer much better protection than green. Clear bottles offer none, so minus some macro-produced beers that use hop extracts modified to prevent the UV reaction (hello, High Life! I love you!), clear bottles will display the flavors and aromas that accurately describe “skunked.” Heck, even draft beer on a nice sunny day will start to display skunky aromas and flavors if they’re sitting in direct light for too long. Perhaps you’d like a lime wedge?
If we look past the part of the beer fan market that hoards high-ABV beers in various pantries, garage fridges, and linen closets, beer is first and foremost an incredibly perishable product. This isn’t like wine, designed for storage and aging with the grace of Horace Grant. Beer is as good as it gets coming off the canning/bottling/kegging line and begins to die from there.
“Beer is a perishable product filled with aroma and flavor compounds from hops, malt, yeast, and maybe additions like fruit that all combine to form a certain tasting experience,” Lange said. “These compounds can change and degrade over time, which alters the flavor, aroma, and appearance of a beer.”
The biggest factor in accelerating the degradation is oxidation, a self-sustaining and unavoidable reaction that draws every beer toward a black hole of cardboard flavor.
“Oxidized beer has a characteristic cardboard or sherry-like stale flavor, is darker, has less hop character, and can display out-of-place caramel notes,” Lange said.
The wet-cardboard event horizon of oxidation is sped up by warmer temperatures. Storing beer cold will keep it fresh for much longer. Forgetting it in your car, Lange said, can have a devastating effect very quickly.
“Hot storage is especially devastating to beer—a beer that still tastes fresh after 90 days of room temperature storage will start to taste stale after only a day or two at 100F,” Lange said.
So it’s not the change in temperature (especially between a 38-degree fridge and a 70-degree shelf) that spoils beer, but the time spent at higher temperatures. Like many repeatedly disproven myths, this one does have a lining of truth to it if you kind of squint and turn your head.
Which, of course, is the most annoying kind of persistent misconception.
“I dislike this myth!” Allagash brewmaster Jason Perkins told me over email. “The message should be simply, ‘reduce the amount of time the beer is stored warm.’”
As it happens, the team at Allagash also felt strongly enough about this topic to write about it a few years back. There are DOZENS of us. And we will not be silent.
Ultimately, this myth persists because it seems plausible, and there’s a small gleam of scientific truth to it. But hey, now you know. So don’t be afraid to buy from the cooler, even if you don’t have the fridge space for it right when you get home. It’s totally okay. A beer scientist promised you!