[klickitat jim]

Did an actual skunk pay a visit when you had your back turned?

[majorvices]

"Sunlight .... on my IPA .... makes me unhappy"

John Denver

[Jimmy K]

A little story about how fast a well hopped beer can skunk:

I was hanging out with some friends getting ready to grill some food on a beautiful sunny day.  I poured myself an IPA and walked outside to fire up the grill. I set my glass on the deck railing (in direct sunlight), lit the grill, turned around and grabbed my beer, put it to my nose and it was skunked  It was maybe 20 seconds!

Sorry but I am a little skeptical. Drinking beer in the sun is not uncommon. If this were true, beer gardens, beer festivals, tailgate parties, and more would serve horrible beer.

[Stevie]

Basic brewing did a video regarding skunky beer.

http://youtu.be/oZuHmglowJA

[majorvices]

A little story about how fast a well hopped beer can skunk:

I was hanging out with some friends getting ready to grill some food on a beautiful sunny day.  I poured myself an IPA and walked outside to fire up the grill. I set my glass on the deck railing (in direct sunlight), lit the grill, turned around and grabbed my beer, put it to my nose and it was skunked  It was maybe 20 seconds!

Sorry but I am a little skeptical. Drinking beer in the sun is not uncommon. If this were true, beer gardens, beer festivals, tailgate parties, and more would serve horrible beer.

Don't be too skeptical, it's happened to me on a number of occasions. I've left a glass of IPA in sunlight for a few minutes and could pick up skunky notes. Not saying the beer was ruined. But the notes were there.

I can remember a story from Matt Brendleson on BN where he said he had hop residue on his hands and clothes and walked into sunlight and he smelled like skunky weed.

[pinnah]

"Sunlight .... on my IPA .... makes me unhappy"

John Denver

 , glad I am not the only one.

"Sunshine..on your I pee A...will make you cry"

[Jimmy K]

Don't be too skeptical, it's happened to me on a number of occasions. I've left a glass of IPA in sunlight for a few minutes and could pick up skunky notes. Not saying the beer was ruined. But the notes were there.

OK, I will be less skeptical.

I can remember a story from Matt Brendleson on BN where he said he had hop residue on his hands and clothes and walked into sunlight and he smelled like skunky weed.

Wait, doesn't the reaction need ethanol? Or is it something else not present before fermentation? This is why we can boil in the sunlight, but not ferment.

[HoosierBrew]

Gotta love a good John Denver reference.  Nothing cheesy about those tunes.         

[dkfick]

Yeah I think they say the reaction takes about 15 seconds to cause your beer to become lightstruck in direct sunlight.  Lighter beers get hit faster than darker beers.  Hoppier beers before less hoppy beers. I've had it happen to me far more often than I would like....

[denny]

A little story about how fast a well hopped beer can skunk:

I was hanging out with some friends getting ready to grill some food on a beautiful sunny day.  I poured myself an IPA and walked outside to fire up the grill. I set my glass on the deck railing (in direct sunlight), lit the grill, turned around and grabbed my beer, put it to my nose and it was skunked  It was maybe 20 seconds!

Sorry but I am a little skeptical. Drinking beer in the sun is not uncommon. If this were true, beer gardens, beer festivals, tailgate parties, and more would serve horrible beer.

I can attest that it really can happen that fast.

[morticaixavier]

Don't be too skeptical, it's happened to me on a number of occasions. I've left a glass of IPA in sunlight for a few minutes and could pick up skunky notes. Not saying the beer was ruined. But the notes were there.

OK, I will be less skeptical.

I can remember a story from Matt Brendleson on BN where he said he had hop residue on his hands and clothes and walked into sunlight and he smelled like skunky weed.

Wait, doesn't the reaction need ethanol? Or is it something else not present before fermentation? This is why we can boil in the sunlight, but not ferment.

There was some info a while back that seemed to indicate it required yeast byproducts, not ethanol in particular but the reactions between the hop compounds that get skunky and the yeast are related to the skunking reaction. However, more recently there was some research that seemed to indicate that it can still happen pre fermentation but not as much or as quickly. However, if you've got hops hash all over your fingers and clothes I bet it can happen pretty quick.

[jeffy]

Ray Daniels wrote up something on this in an old Zymurgy if someone has the time to search it out.  There must be riboflavin present (I think) which is a byproduct of fermentation.  The beer must be light penetrable, if that's a word, so the lighter the beer the quicker it is light struck.  Also the hoppier the beer the more it will stink.
I remember going out into the beer garden of a brewpub once and asked for a paper bag for my pint.  I hate skunky beers that much.  My wife thinks I'm overly geeky, but at least my IPA will smell good.

[bluesman]

A little story about how fast a well hopped beer can skunk:

I was hanging out with some friends getting ready to grill some food on a beautiful sunny day.  I poured myself an IPA and walked outside to fire up the grill. I set my glass on the deck railing (in direct sunlight), lit the grill, turned around and grabbed my beer, put it to my nose and it was skunked  It was maybe 20 seconds!

Sorry but I am a little skeptical. Drinking beer in the sun is not uncommon. If this were true, beer gardens, beer festivals, tailgate parties, and more would serve horrible beer.

I can attest that it really can happen that fast.

+1

I inadvertantly tested this a couple of summers ago, when I left a fresh (unskunked) glass of Pilsner to sit on my deck railing in full sun for about 10 minutes. The beer was moderately skunky in aroma and had a distinct skunky flavor upon tasting. Leaves no doubt that this reaction will occur if given the opportunity.

[ynotbrusum]

So is it the UV rays, predominately, or can this happen from an incandescent light bulb?  What about opaque fermenters (buckets or similar) in a fermentation chest with a regular light bulb as the heat source?

[denny]

UV is the issue.  AFAIK, no problem with incandescent.