[Iliff Ave]

My last two pale lagers with w34/70 have had an off flavor that really bugs me and that I have posted about before. I get kind of the stinky feet isovaleric acid thing but that doesn't appear to be the problem as most equate that to old hops.

I use the accelerated lager method. By rushing these too much or pulling of the yeast to soon cause flavor problems like this? What about underpitching? In both cases the flavor starts to show up after about a week in the keg.

I will add I have never detected this flavor in any other beer I have brewed; ale or lager. It accentuates the malt character. I have tasted it multiple times in other local pale lagers and am more sensitive to it than my friends seem to be.

[majorvices]

So you are saying cheesy? Isovaleric is more cheesy than stinky feet to me. You sure it isn't the hops?

[Iliff Ave]

So you are saying cheesy? Isovaleric is more cheesy than stinky feet to me. You sure it isn't the hops?

Definitely more sweaty gym sock if that makes sense and it seems to come through in the flavor and not aroma. The last lager improved immensely after a couple of months which makes me think it is not an infection however it seems to come on like an infection. The current beer tasted fantastic as it was carbing but then I started to taste the flavor and it has gotten stronger.

I don't think it is the hops but I can't be sure. Some were from brand new sealed bags and some were not. They are different beers with different hops as well.

[tommymorris]

Could it be sulfur?

[Iliff Ave]

Could it be sulfur?

I don't believe so but maybe I am misidentifying it.

[tommymorris]

Could it be sulfur?

I don't believe so but maybe I am misidentifying it.

Since it goes away eventually and smells I thought maybe sulfur.

Sulfur is usually described as rotten eggs. That's what I smell from the fermenter when sulfur is out gassing. But in the beer, I think the taste is more complex and I am not sure I can adequately describe what I associate with sulfur. I think sulfur  comes across as similar to  skunked flavor to me.


This article has a table of descriptors which may help.

https://www.morebeer.com/articles/sulfur_compounds_in_beer

[The Beerery]

I would find it highly unlikely with that yeast and that fermenatation schedule. 

[Iliff Ave]

I would find it highly unlikely with that yeast and that fermenatation schedule.

Do you have any feedback as to what it likely is?

[hopfenundmalz]

I had a beer years back that smelled of old dirty socks. It was the only one I had like that, and attribute it to some Glacier whole hops that had not been stored properly before I got them, it was a 1 lb bag. Yep isovolaric acid.

[Iliff Ave]

Alright well I thought there might be a more common explanation possibly regarding a poor lager fermentation or rushing them. I do remember pushing these beers more than I should have.

[majorvices]

You should be able to pick it up in the hops themselves if it is isovaleric acid. However, not meaning to overlook the obvious but: when was the last time you cleaned your lines?

[beersk]

Could it be sulfur?

I don't believe so but maybe I am misidentifying it.

Since it goes away eventually and smells I thought maybe sulfur.

Sulfur is usually described as rotten eggs. That's what I smell from the fermenter when sulfur is out gassing. But in the beer, I think the taste is more complex and I am not sure I can adequately describe what I associate with sulfur. I think sulfur  comes across as similar to  skunked flavor to me.


This article has a table of descriptors which may help.

https://www.morebeer.com/articles/sulfur_compounds_in_beer

Sulfur can also present itself in a burnt match smell.

You should be able to pick it up in the hops themselves if it is isovaleric acid. However, not meaning to overlook the obvious but: when was the last time you cleaned your lines?

Yeah, this reminds me that I should probably clean mine as well. But he said it was only in this beer, I believe.
The only time I've had this type of off flavor/aroma, I've attributed it to old hops, whether stored properly or not, I think they can go stale over time from opening and resealing, etc. which is why I plan to start buying my hops by the 4oz bag.

[Iliff Ave]

You should be able to pick it up in the hops themselves if it is isovaleric acid. However, not meaning to overlook the obvious but: when was the last time you cleaned your lines?

The hops smelled fine.

That's a good thought. It's been a while. I flushed the lines with star san when swapping the full keg for the empty keg but did not officially clean them. I think that the other lager that exhibited the off flavor may have been on the same tap but I cannot recall...

[reverseapachemaster]

I've brewed several beers with 34/70 around 65F using typical ale timeframes (several days of primary fermentation and packaged 10-20 days after pitching). No off flavors. If yeast are the culprits it would be a defect in your process (e.g. severely underpitching or pulling off the yeast way too early) rather than the choice of yeast or using an accelerated schedule.

[Iliff Ave]

I've brewed several beers with 34/70 around 65F using typical ale timeframes (several days of primary fermentation and packaged 10-20 days after pitching). No off flavors. If yeast are the culprits it would be a defect in your process (e.g. severely underpitching or pulling off the yeast way too early) rather than the choice of yeast or using an accelerated schedule.

Good to know. 34/70 is the only lager yeast I have used and have had no issues. I reached FG then crashed for a few days before kegging.

I really hope that dirty lines is the culprit however I seem to remember that cleaning the lines for the older lager made no difference...