Stouts going sour

No. Your specific examples may help fuel discussion.

I know some big ba beer brewers have started pasteurizing to combat this issue.

(but yeah I can’t stomach sour stouts).

 

I've only had two instances of this and in both, the seal had been compromised. It wasn't readily apparent because there was wax on it and when I removed the wax there was some rust formation on the cap. There could be bacterial infection beforehand, in which case, the brewery should be informed because that would detrimental to the whole batch.

 

I believe in the past we would refer these beers as being infected.
Could this be it, or something different?

 

If you're sure that the sour taste isn't just bitterness coming from some highly-roasted malt, then an infection from wild yeast or some other critter is the next likely cause. Poor sanitation during the packaging process is the likely reason for this happening. If the beers that you're seeing this sourness are all coming from the same brewery, heaven help them.

 

I had a bad bottle of BCBS in 16. It tasted like cherry pie filling. I've also had some soy sauce bombs but that's a matter of oxidation. In the case of my BCBS it was a bacterial infection from a bacteria that was formerly considered a non soiling bacteria. I've read several instances of big bad baptist variants being infected. I blame the flavorings.

 

I drink a lot of stouts and have aged some over the last decade. In my experience, a sharp, sour flavor is the result of infection, either a single compromised bottle, as suggested here, or a batch that had infection problems from the start (very often reported BA). I am guilty of overaging stouts in the past and can say that under normal conditions, they will get oxidation issues and/or a general decline in flavor depth, but rarely sour notes even over long periods. I'm not a fan of sour flavors in stouts, so I've paid attention.

 

I don’t drink may Stouts, but I dabble. If it’s infected what I’ve had has a tart cherry hit to it, I hit some when Duck Rabbit. Had their problems. I’ve had some overaged stouts too, like a 2007 BCBS, I’m guessing it was about 7 years old, it tasted like stale cardboard, so I’m supposing it was oxidation. I’ve never has a sour stout, but I’d guess that would be an infection as well, tart cherry, sour cherry might just depend on the level of infection. Out there somewhere is a Cicerone who should give you the exact explanation.

 

I have not noticed this. The regular stouts have the normal shelf life for me and the imperial stouts can go years.

 

I'd contact the breweries and let them know the batch number if possible.
Some people on this site would probably have been excited to drink a sour stout seeinz as sour beers are all the rage right now.
Even though most are horrible compared to their Belgian counterparts.

 

Sourness is definitely not an attractive characteristic in a stout. I've had a couple that were (allegedly) intentionally soured and it is just not a combination that makes my taste buds merry. I'd suspect an infection of some sort as others have stated already and would suggest contacting the brewery with the pertinent information.

 

The brewers of Guinness would disagree:

--- David Hughes (ex-Guinness Brewmaster), A Bottle of Guinness, Please.

What does this mean? And how would brewing a stout with adjuncts (corn, rice, wheat, oats) cause an infection?

 

Alcohol content plays a big factor for stouts longevity,along with the fact there is little to no hop presence that will fade. Heat and light are beer killers in general. Even if there are adjuncts such as coffee, as long as it is about 10% ethyl or higher it should not go "sour"

 

Well, maybe I should have worded that differently. The few intentionally "sour" stouts I have had were unpleasant to me - like the flavors just don't agree. I'll admit, I was excited about the idea because somehow it made sense in my head, but I was severely disappointed in the taste. I'm open-minded about it - maybe the ones I have had were victims of the "if some is good, more must be better" approach. Or - what I suspect - is that they actually were infected batches that the brwery tried to "save" through creative marketing.

What you describe here seems much more subtle and more along the lines of what I though made sense to begin with.

Cheers!

 

Then these beers were some that were aged by you?

One post above mentioned 10% abv as the threshold to use above which you can consider cellaring beers, but I've also seen 8% as a threshold too. You mentioned above that maybe adjuncts were to blame (I assume you mean flavoring adjuncts) but anything that enters the brewing process before or during the boil should not be a cause because little buggers get killed in that hot liquid. It's after the boil where there is concern, such as during aging in a barrel and during the beer transfer process for bottling/canning, or the container itself. If a beer's label says barrel-aged or the beer spent time in a secondary fermenter on fruit, etc. for flavoring, you're at risk if you choose to age those beers.

 

Gotta agree with the brewers at Guinness that sour can be excellent in a stout. Tart of Darkness is the best example springs to mind, but even the bottles of infected Abyss back in the day tasted pretty good in the beginning stage.