What does UV damage in glass secondary taste like?

[AZWyatt]

So I've been getting a VERY strong off-flavor in my beer for the last five batches or so, and now I'm starting to wonder if I'm exposing them to too much UV light. The glass carboy secondaries are on the ground in my bedroom and are uncovered. There are two windows in my room that let in a good deal of indirect light. Of course, no direct sunlight ever hits them, but enough diffused light through the blinds is let in during the day that I don't really need to turn a light on.

On to the flavor: my Old Speckled Hen clone tastes quite cardboardy to me, but my girlfriend describes the flavor as almost wheatbeer or dunkelwiess-like. It's not skunky, per se, but the taste is bold and overpowering, to the point that the beer tastes nothing like Old Speckled Hen and more like something you want to spit out. The only reason I'm drinking it is because I don't want to have that $30 or so be a waste.

So I ask you, fellow brewers, has anyone ever had an off-flavor that they determined to be caused by UV exposure in a glass secondary? If so, what did it taste like? When did the flavor pop up? Mine tastes fine until a week or two after bottling. FYI, I bottle in amber bottles which are then put away in cardboard boxes.

 

[rdwj]

Ever have a Heineken in a glass bottle? Like that.

 

[Buford]

Cardboardy is oxidation damage. Skunky is UV damage.

 

[BierMuncher]

So I ask you, fellow brewers, has anyone ever had an off-flavor that they determined to be caused by UV exposure in a glass secondary? If so, what did it taste like? When did the flavor pop up? Mine tastes fine until a week or two after bottling. FYI, I bottle in amber bottles which are then put away in cardboard boxes.

I suspect it’s something other than any UV exposure.

A wort in the primary is much to dense with particulates and yeast to really allow sufficient UV rays penetrate. Also, unless the sun hits the primary directly, the indirect light wouldn’t really do anything. Also, UV exposure to beer, usually results in a skunk-like aroma that you almost taste with your sinuses…rather than your pallet.

Cardboard off-taste:

Description: Carboardy, papery flavor or aroma that is not acceptable in any beer style. Sherry-like is another way to describe an acceptable characteristic in many Barleywines, Old Ales, or Scotch Ales.

Cause: Poor wort handling.

Remedy: Do not introduce oxygen to wort after fermentation and avoid rough handling or splashing of hot wort.

 

[olllllo]

Regardless of the problem at hand, do cover your carboy with something. A plastic bag is almost free, right?

 

[Donasay]

Cardboardy or T-bagy often imply improper transfer from primary to secondary for from secondary to bottle. Oxygen is somehow getting to your beer along the line, you need to make sure you don't splash the beer in the fermenters, and that you don't shake the bottles if they have 02 in the headspace. Get the O2 absorbing caps.

 

[TexLaw]

If you kept the box your carboy came in, it's an excellent carboy cover. Just slid it over the carboy, with the flaps on one end extending parallel with the sides of the box. The open flaps give clearance for your airlock.


TL

 

[malkore]

I put t-shirts over carboys to block out the UV rays.

 

[rohanski]

I put t-shirts over carboys to block out the UV rays.

SWMBO covers her carboys with a braw.

 

[AZWyatt]

I thought I ruled out introducing air into the beer, but perhaps I shouldn't. My tubing reaches the bottom of my carboy, I've got a bottle filler and I try my damndest to minimize splashing. I thought for sure it could be UV exposure, but I guess it's not because it's not skunky. And yes, my darker beers do have a sherry-like flavor, so far as I can tell.

 

[teu1003]

... tastes nothing like Old Speckled Hen and more like something you want to spit out. The only reason I'm drinking it is because I don't want to have that $30 or so be a waste.

Let me get this straight ... you drink beer thats fit for "spitting out" so as NOT to waste $30???

Thats a hell of a penance.

 

[TexLaw]

Sherry flavors and aromas most certainly are from oxidation.


TL

 

[BierMuncher]

.. And yes, my darker beers do have a sherry-like flavor, so far as I can tell.

Sherry-like flavors are not unusual in old-ales like Old Speckled Hen. How old is the beer. What were the ingredients.

Instead of looking at the hardware/process, let’s learn a bit more about the recipe.

My OSH has a definite sherry like quality from the addition of invert sugar and dememera sugar. It gets better each week t ages though.

 

[AZWyatt]

The OSH is pretty fresh, only been in the bottle for a couple weeks. I don't have a sherry-like flavor in the OSH, it's only in the pumpkin porter I brewed.

Oh, and they both contribute to a wicked hangover with cottonmouth the likes of which I've only ever experienced the few times I smoked marijuana. But that's probably due to high fermentation temps.