White wine / dry sherry flavour

[Brewer #422640]

Hello,

I've now done about 14 all-grain batches, but the last 3 brews have all had a similar flavour I don't like: white wine or very dry sherry.
The first of the 3 beers that had this was hopped with Nelson Sauvin so I thought maybe I had overdone that hop, but now it's happened with other beers where I haven't used Nelson. The last brew was actually part of a late-addition hop experiment I did, and the 'base' beer was a very simple pale malt grist with Magnum boiled for 30 mins. Even this basic beer has a strong wine/sherry flavour. In that case the flavour was there already before bottling. And I feel the flavour does not seem to be improving with age in the bottles either, if anything I'd say it's becoming stronger, but it's hard to be sure.

My first thought is fermentation temperature. I usually use US-05, and normally get nice results fermenting in my workshop which is really stable around 18-20degC (64-68degF). I also always leave it 2 weeks in the primary and I don't bother opening it to measure gravity.
But the last beers have all been during summer and possibly just happened to be fermenting during quite warm periods here in Sweden. Then the temperature in my workshop climbs to 22-24degC (72-75degF). Then I've read about the actual beer temp being even higher than the ambient, but I'm not sure about this. Is fermentation exothermic?
But could fermenting warm be causing such white wine / dry sherry flavours?
Anyway, the next equipment on my wish list is a fermentation refrigerator so I hopefully will be able to control temp better soon.

Then my second thought is oxidation. My reasoning is because the flavour is similar to if you leave an bit of beer in a glass overnight and take a sip the next day. Dry, back-of-the-mouth wine/sherry for me. I hope my problem isn't oxidation because (I think!) I am careful about this, and I haven't changed my brewing method or equipment recently. But I ferment in a plastic bucket so it is possible I guess that the lid hasn't been sealing well.

Third thought is an acetobacter infection. But I'm quite sure it is not this because I've had this once before and over time it made the beers very carbonated and fizzy in the bottles. It was also much more sour. This is (so far!) not the case for the 3 beers I'm referring to in this post.

Any other thoughts/musings? Thanks in advance!

 

[Zambi]

I've had it happening with one batch in which the temperature was out of control. But seriously out of control.
So it could be that, but your temps don't sound too bad to me.
Fermentis says 18-26 oC, but sometimes yeast does its own thing.

There are much more knowledgable people on here, I'm sure they will chime in

 

[Craigerrr]

Regarding fermentation temperature, yeast are living organisms which produce alcohol, Co2, and heat when consuming sugar, so the actual beer temperature will be higher during fermentation.
Possibly an infection is causing your off flavor, if it is finishing dry a wild yeast may be consuming sugars that US-05 may not.
Try replacing your fermenting bucket.

 

[Megary]

Sherry makes me think oxidation, but “dry” makes me think infection. What are your final gravities? Are your beers finishing lower than what is normal for US-05? In other words, are they finishing dry?

And I get obvious white wine notes from Nelson Sauvin, something I love. But the fact that you keep getting white wine despite not using Nelson is a bit puzzling.

I’m not questioning your cleaning/sanitizing methods because an infection can happen to the most religious cleaners of us all, but if the same off-flavors keep popping up beer after beer then that might be a good place to start.

Good luck. Keep us posted. This is how we all learn.

 

[Dave Y]

Everyone who’s already answered has already pointed you in the right direction. Personally, I’m leaning towards infection due to your comments indicating if anything the off aroma is getting worse.

Last time out I made use of my shiny new 7gpm riptide pump and a clean in place ball right after clearing the fermenter. It wasn’t enough to see shiny stainless, so I rubbed the fermenter down with water, then cleaner, then sanitizer and left the drain open. On a bet, purely by happenstance before putting away I decided to open it up. Good thing I did, I was greeted with a strong odor of hops.

So I got to clean it all over again, this time I let it completely dry and it smelled like.. Victory...

If we can rule that out, one thing I haven’t seen mentioned yet is astringency & tannins. Anything unusual about your mash?

 

[The Brew Mentor]

Sounds like some nasties hiding somewhere

 

[HighVoltageMan!]

Sherry makes me think oxidation, but “dry” makes me think infection. What are your final gravities? Are your beers finishing lower than what is normal for US-05? In other words, are they finishing dry?

And I get obvious white wine notes from Nelson Sauvin, something I love. But the fact that you keep getting white wine despite not using Nelson is a bit puzzling.

I’m not questioning your cleaning/sanitizing methods because an infection can happen to the most religious cleaners of us all, but if the same off-flavors keep popping up beer after beer then that might be a good place to start.

Good luck. Keep us posted. This is how we all learn.

I second oxidation. Sherry flavors are a classic descriptor for oxidation. The white could come from the hops or fermentation. I think you have two separate causes for white wine and sherry.

I just got done working a homebrew competition this weekend. The most common flaw in homebrew are varying levels of oxidation.

 

[Brewer #422640]

Thanks for all the replies so far!

I am now quite sure I have an infection (at least as the main problem).

This afternoon I opened a bottle from the first of these latest 'off brews'. It's been in the bottle for 4 months. I was quite happy with it at the beginning, and although it has been quite 'raw' and dry, I've happily drunk a fair amount of it.
Today I opened it at room temp and it gushed out. It's gone sour and fizzy, and close to undrinkable now. It's a similar flavour to the brew I did last year that definitely got infected - that one was undrinkable even before bottling.

I also opened another from a younger brew (the Nelson Sauvin brew) - it's had 2 months in the bottle. This was dry and winey from the beginning (in part due to the hops), but it's now getting more sour and has similar profile to the one above. It's also already too fizzy even though I generally underprime because I bottle and drink them quite slowly.
Actually it's the fizziness that really gets me. I can accept some unintentional sourness/bacterial nastiness, but if it explodes in fizz when it hits the tongue it's really not pleasant to drink.

It also adds up that it has flared up in the last few weeks as the ambient temp has been higher where I store my beer. I guess a bacterial infection will be happy about that.

I'd be the first to admit my sanitation is pretty relaxed so I will tighten up for the next brew. I can already list a load of things I could have cleaned sanitised better

 

[Dave Y]

Thanks for all the replies so far!

I am now quite sure I have an infection (at least as the main problem).

This afternoon I opened a bottle from the first of these latest 'off brews'. It's been in the bottle for 4 months. I was quite happy with it at the beginning, and although it has been quite 'raw' and dry, I've happily drunk a fair amount of it.
Today I opened it at room temp and it gushed out. It's gone sour and fizzy, and close to undrinkable now. It's a similar flavour to the brew I did last year that definitely got infected - that one was undrinkable even before bottling.

I also opened another from a younger brew (the Nelson Sauvin brew) - it's had 2 months in the bottle. This was dry and winey from the beginning (in part due to the hops), but it's now getting more sour and has similar profile to the one above. It's also already too fizzy even though I generally underprime because I bottle and drink them quite slowly.
Actually it's the fizziness that really gets me. I can accept some unintentional sourness/bacterial nastiness, but if it explodes in fizz when it hits the tongue it's really not pleasant to drink.

It also adds up that it has flared up in the last few weeks as the ambient temp has been higher where I store my beer. I guess a bacterial infection will be happy about that.

I'd be the first to admit my sanitation is pretty relaxed so I will tighten up for the next brew. I can already list a load of things I could have cleaned sanitised better

I had a feeling. I lost about 2.5 gallons of porter to an infection about 3 years back. It crept up on me because the beer had bit of bitterness in it already. I went about 10 or more days and came back to it ( I have 9 taps on hand ) and it was as you describe. A sourness had crept in. I was in denial at first, let it sit overnight and tried again the next day and bleh.

I feel for you.

 

[Craigerrr]

Here is a post I made several years ago, my first failure. I have had a few others as well.
Brew, learn, repeat!

https://www.brewersfriend.com/forum/threads/sour-stout.9009/

 

[Sandy Feet]

I like to keep Starsan in my fermenter for a few days before I brew. When I bottled, the bottles went in the dishwasher, rinsed, and then in Starsan. My keg sits in Starsan for a few days. All my brewing utensils sit in Starsan. You get the picture. In the summers inland here it is in the 90sF, and it feels like 105 or 110 with the humidity. I was in my garage today for about 20 minutes this afternoon, and I looked like I did when I was in the ocean earlier today. We have to have a refrigerator and very ridged sanitation.
Being wet from the ocean is much better than sweating your ass off, and there wasn't a huge tarpon swimming by me in the garage. LOL.

 

[Dave Y]

I keg, so when I have enough I pop them, clean with a hose and brush with water. Then repeat with pbw. Once dry, I repeat with starsan, seal them and that’s it for them. The brew kettles and fermenters take a bit more work by way of scrubbing but, basically the same process.

It took me about 45 minutes to harvest yeast today start to finish and I was drenched in sweat 15 minutes in. I spent the morning cleaning up felled tree debris from the 30 -- yes, thirty, downed trees; dead and dying that I had whacked a few weeks back. Way too much to burn, so I have to haul off most to the dump. I won’t be able to make a full pass with the mower again this year.

 

[Limey]

I keg, so when I have enough I pop them, clean with a hose and brush with water. Then repeat with pbw. Once dry, I repeat with starsan, seal them and that’s it for them. The brew kettles and fermenters take a bit more work by way of scrubbing but, basically the same process...

I also keg and follow a similar procedure except that I clean the kegs with OxyClean, flush and let them dry. I fill them with StarSan (and foam!) just prior to re-filling with beer.

Brew kettle (Anvil Foundry) I just clean the crud off after use - Boiling takes care of sanitation there!

Fermenter - same as the kegs. Clean with OxyClean then sanitize with StarSan just prior to use.

So far (touch wood) I haven't had any infections - StarSan is a contact cleaner (even the foam works) and IMHO is the best for safe brewing!

 

[Craigerrr]

One thing I do to mitigate oxygen is:
Once keg is properly cleaned, I fill it to overflowing with starsan, then push it back out with Co2. I have a spare keg that I use to store starsan, it lasts indefinitely if stored properly.