Does the color of your beer bottle actually matter?

Whether they prefer brown, green, or clear glass, people often talk about some shades being better than others. And green, in particular, has a reputation for leading to “skunked” beer. (Some consumers even seem to prefer it for this perceived effect.) That “skunked” flavor profile is quite a bit different than some of the IPAs on the market aiming for more of a subtle, fresh hop “skunk” effect, however. And it turns out that some bottles really are better at keeping it out than others.

Anyone encountering an off-aroma of this nature is in fact experiencing a beer that has undergone a chemical reaction, or that has been lightstruck. According to beer writer Christopher Bird, certain hop components are so sensitive that when strong light hits them photo-oxidation occurs. This interaction results in one of the most potent flavors on earth: MBT (or, more specifically, methyl-butene-thiol). And this pungent odor compound mimics the notorious defense spray from that highly avoided and often trigger-happy mammal, the skunk.

Bird notes that the blue part of the visible spectrum is most responsible for creating such lightstruck flavors, and that in very strong sun the reaction is so quick that experts notice aromatic changes to a beer after less than 10 seconds of exposure. Hard to believe, I know. Artificial lighting can also have this effect, but takes much longer. As you’ve probably already guessed, or perhaps know, green or clear glass offers almost no protection from light exposure. Brown glass, on the other hand, is very good at protecting against short-term or low-intensity light.

Some companies have developed and incorporated less-light-sensitive hop extracts that are far more shelf-stable. But, an important thing to remember, according to Bird, is that there are other flavor changes that can occur as a result of light exposure, and some are completely unrelated to hops. Either way, such issues have not prevented quite a few breweries from sticking to their beloved green or clear glass bottles. And, for whatever reason — be it branding or cost — plenty of breweries continue to put their beer into such light-vulnerable glass. Apparently, the consumer has not altered their preferences enough to make the leap toward brown glass, or other options. But, for my money, you can keep the glass. I’ll take the opaque option: a can.

— This week’s recommendation: Stillwater “Shoegaze,” a Farmhouse Ale with light herbal, and lemongrass character. 6% ABV. Baltimore, MD