This term, so loosely thrown around by pseudo beer connoisseurs everywhere deserves some attention. Let me set the scene for you…
You are at a gathering at a friend’s house. For the most part, the bud light is flowing. In walks captain cliche with a pair of Sketchers, an iPhone, and a highly sophisticated case of Heineken he just purchased at Walmart. As he esoterically asks for a bottle-opener, another, even more sophisticated attendee sipping on his Killian’s says, “whoa…keep that skunky beer away from me!” Another guy with a sweet man-purse says, “Yeah, those Dutch guys need to invest in some brown bottles!”
All three of these guys are idiots.
It never occurred to guy one that Heineken isn’t as cool as the commercials make it out to be. (Although I am impressed with Heineken‘s ingenuity–the time spent on their pressurized mini-kegs was genius marketing).
It never occurred to guy #2 he should have kept his mouth shut. I don’t believe that Heineken (or other so called skunky beers; i.e. Stella Artois, Grolsch, St. Pauli Girl…) are actually skunked beer. Beer is a science. The skunky smell and unique flavor of said beers is quite intentional. That sulfur-ish smell and flavor may result from a delicate and precise combination of grains and yeast, interacting in and changing each other in the turbulent fermentation process.
Guy #3 (who most definitelty likes the sound of his own voice) may be on to something, but is overwhelmingly wrong. Green bottles may affect the quality of beer, but most likely only marginally.
The fact is, skunked beer is not desirable. It is a flaw, not intended by the brewer. Last Friday, Mike noted that his Sierra Nevada Pale Ale had that skunked quality. The Sierra Nevada beer I drank, miles away, most likely having being born of a different batch than Mike’s was not skunky. Obviously, the brewer is going for uniformity in his beer, so something went wrong.
Beer becomes ‘skunked’ when it is unintentionally exposed to light; more specifically, UV radiation. That is why it is imperative for beer to be kept out of sunlight and fluorescent lighting, which emits far more UV radiation than an incandescent light bulb (fluorescent light bulbs don’t use a burning filament, rather excited ions resulting in plasma, the fourth state of matter, unique only to the sun and nuclear reactions…which makes me wonder…should the EPA be pushing so hard for these creepy bulbs?)
Anyway, when UV light streams through a bottle of beer, the hop compound (an acid used not just for flavor (bitter) but also for preservation), as well as sulfur compounds in the beer are chemically altered from the energy. As I said above, beer is a science. The energy transforms the acids into 3-methyl-2-butene-1-thiol (thiol indicates sulfur). As we all know, sulfur is known for having a pungent, offensive odor. Stink bombs, well water, and skunks all utilize this element to drive people away.
The myth is busted. Skunk beer is not a desirable trait, although many folks tend to think so and thus many brewers go after this effect naturally. However, they are not brewing a bunch of beer in green bottles and letting them sit out in open sunlit fields. You can avoid skunked beer by drinking your beer in the underground leaded fallout shelter in your basement like I do.