Uh oh. Wild yeast? Infection?

[Miraculix]

Update: (Not on the OP's wild yeast infection, but on my own very first crude and deliberate attempt at open/wild fermentation, inspired by this post - see above)

I got pretty decent activity in my open bucket after 24h, with plenty of krausen building up. I let it ferment for a few more days and bottled in PET plastic 1L bottles, for safety. The wort did not give off the usual yeasty smell, but it was not unpleasant, either. Clearly there was plenty of fermentation still going on, because the bottles puffed up rock hard after a couple of days. Even after refrigerating, the bottles gushed almost uncontrollably.

The result? Nothing smelling or tasting like (normal) beer. I took a whiff and a few sips. It had what I would describe as a sanitized hospital ward smell. Something like isopropyl alcohol. Perhaps like the band aid smell folks sometimes identify in brettanomyces. I dumped the whole small batch (it was just over 4L/1G of leftover wort from my "real" brew). If I was in prison or in a desert island I could see myself drinking it. It did not have a nasty taste, but definitely not good either. Is it likely that I just got a pure brett brew? On a positive note, I'm still very alive.

On a final note, can anyone point me to a good guide to help recognize and identify the most common "off flavors" (that can also be intentional components of some beers)?

Wild brews need time. They really need a lot longer then "normal beers". The reason is, that they are going through stages and these stages do not taste pleasent. If you would have waited longer, chances are high that other yeasts/ micro organisms would have taken over and either got rid of the off flavour causing components or masked them or whatever else might have happened there. The earliest wild beer I have ever heard of was ready for botteling after 3 months. But much more common is 6 to 12 months or longer. I have a wild mead here that started to be drinkable after 1.5 years and continually gets better and better..... so next time, give it wayyy more time.

But if it REALLY tastes like vomit, crap whatever, something went wrong, dump it.

 

[Andres Falconer]

Wild brews need time. They really need a lot longer then "normal beers". The reason is, that they are going through stages and these stages do not taste pleasent. If you would have waited longer, chances are high that other yeasts/ micro organisms would have taken over and either got rid of the off flavour causing components or masked them or whatever else might have happened there. The earliest wild beer I have ever heard of was ready for botteling after 3 months. But much more common is 6 to 12 months or longer. I have a wild mead here that started to be drinkable after 1.5 years and continually gets better and better..... so next time, give it wayyy more time.

But if it REALLY tastes like vomit, crap whatever, something went wrong, dump it.

Thanks for the feedback! I am really just dipping my toes into this wild world, and I will take this into account next time. Unfortunately time is something I did not have on this occasion, since we are about to leave the location where we spent most of the pandemic, and would not be able to carry the brew, nor have anywhere appropriate to store it for the coming months. I've learned a thing or three... and will be better prepared next time!

 

[Miraculix]

Thanks for the feedback! I am really just dipping my toes into this wild world, and I will take this into account next time. Unfortunately time is something I did not have on this occasion, since we are about to leave the location where we spent most of the pandemic, and would not be able to carry the brew, nor have anywhere appropriate to store it for the coming months. I've learned a thing or three... and will be better prepared next time!

If you have a nice and tight plastic fermenter like Speidel or similar, that would be best. It leaves through micro doses of oxygen, which is good in this case, but not as much as a bucket. Once you have this brew going, you can easily put it somewhere in the back of the basement and forget about it for a year. The only thing you have to take care of, is that the airlock is not drying out, so check every month or two. So if you know that you are going to stay for longer at one place, you can start

 

[Garrett_McT]

Update: (Not on the OP's wild yeast infection, but on my own very first crude and deliberate attempt at open/wild fermentation, inspired by this post - see above)

I got pretty decent activity in my open bucket after 24h, with plenty of krausen building up. I let it ferment for a few more days and bottled in PET plastic 1L bottles, for safety. The wort did not give off the usual yeasty smell, but it was not unpleasant, either. Clearly there was plenty of fermentation still going on, because the bottles puffed up rock hard after a couple of days. Even after refrigerating, the bottles gushed almost uncontrollably.

The result? Nothing smelling or tasting like (normal) beer. I took a whiff and a few sips. It had what I would describe as a sanitized hospital ward smell. Something like isopropyl alcohol. Perhaps like the band aid smell folks sometimes identify in brettanomyces. I dumped the whole small batch (it was just over 4L/1G of leftover wort from my "real" brew). If I was in prison or in a desert island I could see myself drinking it. It did not have a nasty taste, but definitely not good either. Is it likely that I just got a pure brett brew? On a positive note, I'm still very alive.

On a final note, can anyone point me to a good guide to help recognize and identify the most common "off flavors" (that can also be intentional components of some beers)?

I would suggest the book titled Yeast: The Practical Guide to Beer Fermentation by Chris White and Jamil Zainasheff. I haven’t read the whole book, I use it more as a reference book whenever I have questions or troubleshooting. They go in depth into the science of yeast before talking about very specific applications and processes behind brewers yeast. They even have a whole section of home brew versions of lab scale quality control tests for yeast. I haven’t read these sections in depth but they do have two subsections of the book on brettanomyces and “Capturing Wild Yeast”

the book is one part of a four part series from the Brewers Association on the four main beer ingredients. I also have For the Love of Hops: The Practical Guide to Aroma, Bitterness and the Culture of Hops from the great Stan Hieronymus.

 

[Andres Falconer]

I would suggest the book titled Yeast: The Practical Guide to Beer Fermentation by Chris White and Jamil Zainasheff. I haven’t read the whole book, I use it more as a reference book whenever I have questions or troubleshooting. They go in depth into the science of yeast before talking about very specific applications and processes behind brewers yeast. They even have a whole section of home brew versions of lab scale quality control tests for yeast. I haven’t read these sections in depth but they do have two subsections of the book on brettanomyces and “Capturing Wild Yeast”

the book is one part of a four part series from the Brewers Association on the four main beer ingredients. I also have For the Love of Hops: The Practical Guide to Aroma, Bitterness and the Culture of Hops from the great Stan Hieronymus.

I have the book, though not with me at the moment. I found it fascinating, though heavy on the science and less so on the "how tos".

 

[Andres Falconer]

If you have a nice and tight plastic fermenter like Speidel or similar, that would be best. It leaves through micro doses of oxygen, which is good in this case, but not as much as a bucket. Once you have this brew going, you can easily put it somewhere in the back of the basement and forget about it for a year. The only thing you have to take care of, is that the airlock is not drying out, so check every month or two. So if you know that you are going to stay for longer at one place, you can start

I may do as you suggest, Miraculix! The cellar is in my mother-in-law's house, in a little town in Lithuania. It's not temperature controlled, but it is cool and somewhat stable. It may go down to 10C in winter and 18C in a summer heatwave. I'm thinking of starting it off in a bucket in our house, then transferring to a carboy and "lagering" it off in her cellar for a year, until we're back next summer. Will that work? I'm sure she'll be good at monitoring the airlocks (I'm already leaving several 5L carboys of different meads with her!)

I still have many questions... Is hopping important (other than for taste), or can hops get in the way, since you're actually trying to get the wort "infected"? Is a "raw" (unboiled) wort a good idea, since it can pick up yeast from the unpasteurized mash? This will be my final "Covid-brew" before returning home, with my last remaining supplies. I think all I have is a few kg of Maris Otter. It will have to do... I realize I don't have much to lose, and will have something to make me look forward to visiting the mother-in-law!

 

[Garrett_McT]

I have the book, though not with me at the moment. I found it fascinating, though heavy on the science and less so on the "how tos".

Ya you’re right it is a bit heady. But honestly if you invest the time and understand a brief general info of the science, it will go a far way. If you understand the background you will understand how the yeast will behave and be able to make judgements on your own.

in absence of how tos, I have found and come to this forum! Tremendous help!

 

[Miraculix]

I may do as you suggest, Miraculix! The cellar is in my mother-in-law's house, in a little town in Lithuania. It's not temperature controlled, but it is cool and somewhat stable. It may go down to 10C in winter and 18C in a summer heatwave. I'm thinking of starting it off in a bucket in our house, then transferring to a carboy and "lagering" it off in her cellar for a year, until we're back next summer. Will that work? I'm sure she'll be good at monitoring the airlocks (I'm already leaving several 5L carboys of different meads with her!)

I still have many questions... Is hopping important (other than for taste), or can hops get in the way, since you're actually trying to get the wort "infected"? Is a "raw" (unboiled) wort a good idea, since it can pick up yeast from the unpasteurized mash? This will be my final "Covid-brew" before returning home, with my last remaining supplies. I think all I have is a few kg of Maris Otter. It will have to do... I realize I don't have much to lose, and will have something to make me look forward to visiting the mother-in-law!

Sounds good!

Mash is naturally held at pasteurisation temperature, there is basically nothing left to culture so nothing to win from this side. Just boil as usual.

Hops are important, even if they are not. Traditional Belgian Lambics are hopped with "aged" hops. They have lost most of their antimicrobial properties, but still have a bit left so that they can be used to limit the sourness a bit. Because this is what a beer without hops becomes, it becomes sour. Either through lactic bacteria, which do not need oxygen and convert sugar into lactic acid, or by acedic acid bacteria which can turn alcohol into vinegar, but these guys need oxygen. Lactic acid bacteria cannot tolerate hops, so you can stop the souring by using enough hops in addition to limiting the oxygen contact. Smaaall doses of oxygen might be beneficial, but these doses will get into the fermenter with time anyway if made out of plastic, so no action to be taken.

So you can either not hop and get something very sour, hop a little, let´s say 3-10 ibus and hope for the best (might still turn out very sour, or not sour...) or you can hop like a "normal" beer and possibly get something not (so) sour. A certain twang based on the wild yeast might appear, or it might not, that is the beauty of it.

You might want to add a bit of wheat (flour) to the grist, at least this is what the belgian guys are doing. 20-30% flaked wheat or wheat flour is not unusual. If you already have a basemalt shortage, this should come handy for you.

Good luck!