Few
beer tasting terms are more descriptive or straightforward than
"skunky." Quite simply, a skunky beer emits an aroma it didn't have
when it left the brewery.
The
smell is the product of the chemical reaction that takes place in the bottle
when bright light strikes the hops, creating what's technically known as
"light struck" beer. The reaction is stronger with paler and hoppier
beers. The resulting chemical is identical to that in a skunk's defense system,
and light-struck beer puts off one of the most powerful aromas around.
Clear
and green bottles do very little to protect a beer from skunking, and while
dark brown bottles are much better they are far from perfect. Many of the imports
come in clear or green bottles, and are more expensive beer (consumers have
come to associate a skunky aroma with imported). The brewers did not intended
them to taste that way.
The
brighter the light and the longer bottles sit in that light the stronger the
skunky smell will be. Even dark brown bottles won't guard a beer from the bright
fluorescent lights in grocery stores and other beer retailers.
In
some stores you'll see six-packs sitting on tops of cases. Don't grab that one,
but get your beer from inside the case. If you want beer from the cooler don't
be shy about asking if there are unopened cases in the cooler and buying a
six-pack from one of those.
Buying
beer that has been kept out of the light gives you a better chance of getting a
"skunk free" beer. It's up to you to keep it that way -- mostly by
continuing to keep it out of direct light -- until you drink it.