Author Topic: Light Struck  (Read 2469 times)

Offline coolman26

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Light Struck
« on: April 18, 2017, 06:57:38 PM »
Comments from NHC judges regarding my Kolsch. Both stated it to have a light struck aroma that dissipated as it warmed. Is this yeast related?  I know I've been having oxidation issues. I believe I have this issue figured out. I wondered because it didn't see any type of light. Pitched plenty of healthy Giga021 yeast.  Controlled the temps, and all aspects I thought. Scored 37.5, 36 and 39. Just wondering.....


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Offline stpug

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Re: Light Struck
« Reply #1 on: April 18, 2017, 07:00:10 PM »
What is the aroma you get from "light struck" beer?  I always thought it was what folks called "skunked", but I didn't think that character dissipated as it's warmed.

Offline Phil_M

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Re: Light Struck
« Reply #2 on: April 18, 2017, 07:01:57 PM »
In my experience, beer is either skunked (light struck) or not. Pure binary, no going back.

Maybe there was a sulfurous quality that dissipated? I could possibly see that being mistaken for a skunk stink.
Corn is a fine adjunct in beer.

And don't buy stale beer.

Offline denny

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Re: Light Struck
« Reply #3 on: April 18, 2017, 07:15:10 PM »
In my experience, beer is either skunked (light struck) or not. Pure binary, no going back.

Maybe there was a sulfurous quality that dissipated? I could possibly see that being mistaken for a skunk stink.

Yeah, I have never had skunk dissipate as the beer warmed.
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Offline dmtaylor

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Re: Light Struck
« Reply #4 on: April 18, 2017, 09:11:09 PM »
Much like sulfur, I find minor skunking can dissipate.  I've made a farty beer before (many years ago) where I recall telling my friends "pour it into your glass, then walk away for 5 minutes, then come back and enjoy".  Mercaptan compounds are of course volatile so it makes sense to me that in some cases you could do the same thing to a slightly skunked beer -- pour, walk away, come back and enjoy.  Or, just embrace the skunk.
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Offline Phil_M

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Re: Light Struck
« Reply #5 on: April 18, 2017, 09:19:12 PM »
I'm a huge fan of Heineken, but only from a can/draft.

Skunked beer is awful.
Corn is a fine adjunct in beer.

And don't buy stale beer.

Offline Jkrehbielp

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Re: Light Struck
« Reply #6 on: April 18, 2017, 09:20:14 PM »
The mercaptans that are responsible for skunking are highly volatile. Perhaps a small amount could dissipate.
On a similar note, I've never worried about light exposure during the brewing process. And mercaptans generated should blow off during fermentation

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Offline Phil_M

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Re: Light Struck
« Reply #7 on: April 18, 2017, 09:29:32 PM »
The mercaptans that are responsible for skunking are highly volatile. Perhaps a small amount could dissipate.
On a similar note, I've never worried about light exposure during the brewing process. And mercaptans generated should blow off during fermentation

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I seem to remember that mercaptans can only be produced after fermentation...though perhaps it was boiling?

I've never worried about it during the boil, and my wort is often in direct sunlight. No skunk.
Corn is a fine adjunct in beer.

And don't buy stale beer.

Offline dmtaylor

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Re: Light Struck
« Reply #8 on: April 18, 2017, 10:21:30 PM »
I seem to remember that mercaptans can only be produced after fermentation...though perhaps it was boiling?

I've never worried about it during the boil, and my wort is often in direct sunlight. No skunk.

The boil would drive it off.  I'm sure if you left a glass carboy fermenting in broad daylight, you could pick up some skunk.  However, the action of CO2 production would likely scrub most of it out until towards the end of fermentation.  In similar fashion, I think CO2 from fizz can drive things out when poured into a glass or pitcher.  But if that same glass or pitcher is left in the sunlight, skunk city.
Dave

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Offline hopfenundmalz

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Re: Light Struck
« Reply #9 on: April 19, 2017, 12:07:52 AM »
Riboflavin is involved in the skunking mechanism. It is a product of fermentation.

Hey, a few years back I bottled in the garage, and some sun was shining in through the window in the pedestrian door. Not a lot of time or sun. The sheets said light struck. The control bottle confirmed it.
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Offline Phil_M

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Re: Light Struck
« Reply #10 on: April 19, 2017, 12:42:03 AM »
My primary racking/bottling space has direct sunlight for most of the day...I rack/bottle after dark.
Corn is a fine adjunct in beer.

And don't buy stale beer.

Offline hopfenundmalz

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Re: Light Struck
« Reply #11 on: April 19, 2017, 12:50:56 AM »
My primary racking/bottling space has direct sunlight for most of the day...I rack/bottle after dark.

I now cover the door's window if bottling during the day.
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Offline denny

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Re: Light Struck
« Reply #12 on: April 19, 2017, 01:02:28 AM »
Riboflavin is involved in the skunking mechanism. It is a product of fermentation.

Hey, a few years back I bottled in the garage, and some sun was shining in through the window in the pedestrian door. Not a lot of time or sun. The sheets said light struck. The control bottle confirmed it.

THIS^^^^^^^
Life begins at 60.....1.060, that is!

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"The whole problem with the world is that fools and fanatics are always so certain of themselves, and wiser people so full of doubts." - Bertrand Russell

Offline coolman26

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Re: Light Struck
« Reply #13 on: April 19, 2017, 08:42:00 PM »
Riboflavin is involved in the skunking mechanism. It is a product of fermentation.

Hey, a few years back I bottled in the garage, and some sun was shining in through the window in the pedestrian door. Not a lot of time or sun. The sheets said light struck. The control bottle confirmed it.

THIS^^^^^^^
I'll have to look that up. I know it didn't see light. I figured it was yeast related. How, I'll look that up, thanks. Jeff actually judged it in Indy.



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Offline hopfenundmalz

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Re: Light Struck
« Reply #14 on: April 19, 2017, 10:41:40 PM »
Riboflavin is involved in the skunking mechanism. It is a product of fermentation.

Hey, a few years back I bottled in the garage, and some sun was shining in through the window in the pedestrian door. Not a lot of time or sun. The sheets said light struck. The control bottle confirmed it.

THIS^^^^^^^
I'll have to look that up. I know it didn't see light. I figured it was yeast related. How, I'll look that up, thanks. Jeff actually judged it in Indy.



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I remebered getting one there. Sorry it was yours, seemed good othwise from what I recall.
Jeff Rankert
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AHA Governing Committee
BJCP National
Home-brewing, not just a hobby, it is a lifestyle!