A few months ago I brewed a saison (recipe to follow later) with some bottle cultured yeast from Fouret, which is an organic saison by Dupont. I over sparged and ended up with some extra runnings. I boiled them down to a nice 1.030 to use for future starters, as I often do. I find it makes sense to run off a little extra wort after reaching boil volume and then boiling it down to 1.030 and freezing it to make the starter for my next batch. It’s very little work and it basically means I don’t need to buy DME. Although DME isn’t incredibly expensive, it’s a lot more expensive than a little water and about ten minutes of boiling. As I’ve said before, I look for those opportunities to reasonably reduce costs.
This time I set out to culture wild yeast. I had tried this in the past but I didn’t seem to capture any yeast; just some bacteria that ultimately became part of an interesting, but tasty, beer. In the past I tried to capture yeast off of wild vegetation with wort with nothing added. I did some more research and discovered that adding hops would help deter the growth of a lot of bacteria. So this time I added a little hops, to get to about 8 IBUs, boiled it up, cooled it and added it to a jar. I dipped a peach in and then added the peach skin a few hours later.
For the first few days it stunk like peach-fecal-wort. I suspect this was the arrival of enteric bacteria. A few days later it started to bubble and krausen formed. Sure enough, a few days after this started a thin coat of a white, solid substance begin to form on the bottom and the wort now smelled like, well beer. When fermentation seemed to end, I decanted, added more wort and fermentation started back up. I repeated this process a few more times until I had a solid amount of yeast. While fermenting, the wild yeast had a pineapple smell, something that seems very common among people who catch wild yeast all over the country. I then decanted the liquid, added the yeast to a mason jar and topped it off with water.
I’m sure there is a variety of yeasts in the culture; I’m not a scientist so I’m not equipped to try to separate different species to reduce it down to individual strains. I’m ok with that. I named my wild yeast “Hot Carl”. Hot Carl is a sex reference that I find really entertaining. I’m not into it, it’s just funny! It seemed to fit in my head and that’s all that counts.
I decided to brew a one gallon batch to see what kind of beer Hot Carl makes. In order to figure out what flavor Hot Carl produces I needed to use a clean, neutral recipe that would accentuate the yeast contributions. So here is my generic recipe. (I accidentally bought too much grain and milled it before I realized my mistake, so it ended up being a higher alcohol recipe than expected.)
Estimated OG: 1.069
Estimated FG: 1.016
Estimated ABV: 6.92%
1.5 lb Pale Malt
1 lb Wheat Malt
8 oz Vienna Malt
Boil Volume 2 gallons
.25 oz Fuggles @ 60 min.
.13 oz Fuggles @ 20 min.
I did this brew BIAB-style because of the small volume. I aerated the cooled wort and pitched Hot Carl. Here’s the mash:
The upside of BIAB brewing is it is really, really easy. The downside is that you can’t vorluf so you end up getting a lot of crap from the grain in the fermenter. As you can see here, the wort is very thick. That’s because I just aerated and all the stuff is floating around. It will eventually settle to the bottom. On larger batches I strain before it goes into the fermenter. The larger hop particles get caught and creates a filter to keep the smaller grain pieces out. I don’t have a strainer that works well with the funnel so I don’t really have a choice at this point. The good news is that I hit OG dead on at 1.070 but we’ll see how dry this beer gets.
I left for a while and came back to find fermentation in full swing. This is about fourteen hours after pitching. You can see there is a very thick white layer above the beer. It’s not the thick krausen one normally sees with yeast. It is foamy, kind of like when you aerate beer or you add beer or wort to a container with a lot of starsan. It actually reminds me of how the saison yeasts I cultured from Fournet ferments. Very foamy at first and then settles into a thicker krausen towards the end of fermentation. I don’t know that the pictures well represent what I’m describing but I promise that’s what it looks like. You can kinda tell…
This is about twenty hours after pitching. It is bubbling at a rate of around one bubble every couple of seconds. You can see a little better in these pictures that the krausen is very foamy. You can also see some brown stuff forming at the top of the krausen. (Look where my crappy MS Paint arrow is pointing.) That’s a good sign fermentation is chugging along. That brown stuff is the start of what normally clings to the sides of the fermenter. It sometimes has hops particles but it is mostly very bitter byproducts of fermentation. You WANT that stuff to stick to the side and stay out of the final product.
Just four hours later (34 hours in) fermentation is really taking off. It is about noon and it’s approaching 80 outside and this beer sits in my utility closet, which gets warmer than anywhere else in my apartment because there’s no air flow from the air conditioning, it has vents to the outside for the dryer and it sits up against my neighbor’s utility closet and sometimes he runs his washer and dryer, which makes it much warmer. Needless to say, the fermenter got a little warmer than I wanted it to be. As a result, you can see fermentation is pretty violent. You can see the foam is getting much darker and thicker as it is turning more krausen-like. Looking at the pictures of the airlock where I have the blow off tube connected you can see blow off coming out. So far I’ve lost just a little beer to blow off but with this being wild yeast it’s hard to know how long fermentation will run. Blow off tubes are really important when you’re fermenting in a container with so little headspace. It’s good insurance against having a ceiling full of beer. And yes, it has happened to me. Twice. Lesson learned.
This is about 45 hours after pitching, so about two days later. You can see the top part of the fermenter, where there is headspace, is opaque. The fermentation pushed a very thick layer of gunk on the walls of the carboy. Behind that layer is an inch thick layer of white foam on top of the beer. I removed the bung for a brief smell. It has a saison-like smell to it. It smells a little barnyard-y. That’s a lot of what the culture smelled like when I was capturing Hot Carl its first few days so maybe there will be some changes and more citrus notes will come out as fermentation proceeds. It took about a week to two weeks for that smell to appear, so we will see how this beer proceeds. There is likely some bacteria at play in the fermenter but between the acidity from the hops and the couple of days of fermentation they shouldn’t last for long.
This is 56 hours after pitching, which is about 2.5 days into fermentation. I’ve harassed the fermenter to show what the beer looks like underneath the layer of crap on the sides of the fermenter. Most of the foam has retracted back into the beer although there is still plenty of bubbling through the airlock. Although it is not a great picture, the awesome MS Paint arrows do point you to several pea sized clumps floating on the beer. This is yeast. I’ve been told by other people who have used peaches as a source for wild yeast that it has a tendency to be very clumpy yeast. That should result in a very clear beer if the yeast all clump up because it can be cold conditioned and those clumps should drop very fast. So far a thick yeasty krausen hasn’t formed, but as I remember from the culture it didn’t appear until several days in. There may not be a different krausen forming in coming days. We shall see.
I just noticed by scanning through the pictures you can see, even at this point, at the beer is getting lighter and lighter at each interval. That probably has a lot to do with the crap caking the walls of the fermenter, but regardless it is a good sign.
It’s been about three and a half days and fermentation seems to have stopped. It’s still about the same color but all the chunks and foam have disappeared from the top of the beer. I don’t want to disturb it too much so I didn’t want to tilt it to get a picture. I want to let it sit for at least a couple of weeks to see if it clears up some. At this point I am contemplating bottling it after a couple of weeks, but I may want to let it ride for a while. A big component of that decision will be whether any changes occur. If it gets ropy (indicating Pedio has arrived) or develops another krausen then I’ll pretty much have to leave it in place.
A few hours later I flipped out the blow off tube for an airlock. Although I thought it had stopped bubbling, it appears to be slowly bubbling again in the airlock. It could just be off-gasing, rather than ongoing fermentation.
Here it is 12.5 days after pitching. As you can see from the pictures, there is a thick layer of yeast at the bottom that I will wash and save for future Hot Carl batches. As you can also see, it has cleared up a bit (sorry for the bad reflection off the glass). What you probably can’t see if that there are still some floating balls from the yeast. I’ll need to cold crash this beer before bottling to try to avoid getting any of those things in the bottle. I doubt they are harmful, I just doubt they are aesthetically pleasing to somebody popping open a bottle. There’s no sign of any other pellicle forming, so it doesn’t look like I’ll have any other playmates. I’m sure there is brett in the bottle and it will be interesting to see if any refermentation occurs over time in the bottle. I’ll try to drink these slowly in order to try to see how it changes over time. Honestly, I’ll probably drink a few and then open them to “show off” to other people all the crazy things we do as brewers. Unless it tastes bad, then I’ll let them sit around for a while and see if the flavor changes for the better over time.
I finally bottled this batch after letting it ferment for two weeks, on 11/7. Usually I am more patient with my beers, letting them rest in the fermenter for as much as two months (depending on ABV) before bottling. However, I was really impatient with this one!! I cold crashed in the fridge for a couple of days, which really seemed to help clear out the yeasts. I let the beer warm back up before bottling, which maybe was a mistake because I ended up with a lot of trub in the bottling bucket. Normally I like to take a little taste from the small amount of beer left in the bottling bucket, but there was so much trub I didn’t want to ruin my first impression by tasting trub. I did get some good smells out of it. It smells…wild. I’m not really sure what to equate it to, other than to say it had a lot of funky smell to it.
As I was bottling I started to worry about bottle bombs. Wild cultures will almost undoubtedly contain brett and other slow moving critters that will continue to ferment the beer over time, so if those bottles superattenuate, they will definitely blow. For that reason, I have them stored in a Rubbermaid containers and in sixpack containers, so if they blow up they should just collapse in the sixpack container, or at worst be contained by the plastic container. If that starts to happen, I’ll permanently keep them in the fridge to prevent additional fermentation.
Nine days into bottle conditioning (11/16) the bottles seem to have cleared pretty quickly. There is a lot of sediment in the bottom of the bottles. Far, far more than I have ever seen in any other beers. The average bottle has about half an inch of sediment, with some having almost an inch. I know a lot of grain particles and hop pellet pieces made their way into the fermenter but that still seems like a lot. I suspect a lot more of that is yeast. So far no bottle explosions.
With the beer bottled for a month I gave it a taste. It pours slightly cloudy like a saison. It's a slightly darker beer. Very bubbly but absolutely no head. Even with a vigorous pour it foams up but quickly dissipates. Considering the grain bill is a third wheat malt, that's pretty surprising. It's an interesting blend of flavors. Some citrus flavors with maltiness, a hint of tartness, a hint of funk and a lot of a butterscotchy flavor that might be diacetyl or something different.
Honestly it's very different and I'm torn on whether that butterscotchy flavor is too much. I definitely want to try brewing it again but next time I want to age it with brett. I can see how brett could blend really well into it, especially if it cleans up the butterscotch flavor a little. That will definitely be a future project!