anaerobic ferment using Kombucha yeast

[Thedillestpickle]

I searched everywhere on the internet for results of someone attempting to brew a simple all malt based beer using the yeast from a kombucha culture.
I couldn't find any so I fired up my stir plate and gradually added 250ml jars of premade canned malt extract wort to the yeasty sediment of a batch of kombucha. I removed the "scoby" to promote a more yeast dominant culture. 48 hours later I cold crashed and attempted to remove the very low flocculating yeast from the trub.

Meanwhile I brewed up a 1 gallon 1.045 OG batch is super simple all 2-row wort with just a small pinch of hops.

after 6 hours it was bubbling.
It's now 24 hours and it's been bubbling furiously all day...

I wonder what this yeast will do? It appears that the strain that has taken the biggest hold in the fermentation is an ale strain(forming a thick yeasty krausen on top) and the smell out of the airlock is nearly identical from what you would get out of a primary fermentation using US-05.

 

[Thedillestpickle]

Well this has been a fairly loosely organized experiment. I think I will do a repeat with much more exacting procedure on a 5 gallon scale.

The bottom line however is that I have a gallon of what seems like beer. Primary was done in 48 hours! I racked to a secondary. The samples I tried were tangy and very mellow without any seriously up front flavours to note. Unfortunately the recipe I used for my wort is extremely boring so even if this does condition nice and clean, there won't be much of interest to the finished beer.

I'm not sure what style of beer this yeast would be ideal for but it definately has potential.

My question is, how can this beer not be severely infected? It's from kombucha that ferments open to the air. I simply stepped up whatever that culture was in a stir plate and pitched that culture into a gallon of wort. Or maybe time will tell and the signs of infection just aren't coming through yet?

 

[Thedillestpickle]

No one wants to know how this turned out?

 

[Braumeise]

i do.

Since I have been making my own kombucha since Highschool, I had the same idea to at one point ferment wort with kombucha yeast and see what it turns into,

 

[Thedillestpickle]

Ok. So I'm definitely planning to brew this again at 5 gallon scale. I'm down to only 1 bottle left of this experimental batch. I really like it, and so have two others who have tried it.

It's like a very simple saison with mild but interesting bubblegum and red nibs licorice aromas and flavours. There's no strange sour or anything I would call an off flavour. What the yeast flavour reminds me of the most is "La Fin du Monde" by Unibroue. I find their 9% Belgian Triple style strong ale to be cloying and too intensely yeasty, so this is a refreshing example of those flavours in a much more toned down way. This fermented out to about 1.010 so comes out at around 4.5% ABV.

I will post up a shot of the last glass when I go to drink it.

 

[Braumeise]

I will definitly do this at one point.
Thanks for sharing.
I'll share my results as well as soon as I have some

 

[Thedillestpickle]

Yummy. It's almost all gone now.

I'm really hoping that the yeast that I held on to from the 1 gallon batch is going to perform similarly to what it made the first time around. I'm skeptical about how reproducible my results are going to be because certainly this is more of a yeast "Blend" than it is any specific one strain and so the ratios of each strain may change with subsequent brews.

Here's a shot of the last pint from this small batch.

 

[Thedillestpickle]

That's the chill haze from it being an experimental 1 gallon batch and so not being cooled fast enough. It was clear before it went into the frigde.

 

[Braumeise]

Looks really good! I will totally attempt this and I would drink what you brewed there

 

[tarmenel]

I was thinking about this. I've just started making kombucha and making bigger batches and love the tart flavor. Now that I'm trying my hand at sour's and not having easy access to liquid sour starters I've been looking at different things to sour the beer with. I've already started using sourdough but I also want to make a batch using kombucha. Did you just harvest the yeast from the bottom of your kombucha? How did you build it up to something that you could use in a brew?

 

[Aristotelian]

Interesting. I tried.putting the scoby in wort to make malt vinegar one to.e and it did nothing.

 

[Thedillestpickle]

Interesting. I tried.putting the scoby in wort to make malt vinegar one to.e and it did nothing.

I'm surprised that it did nothing?

I've tried something similar with actually using the scoby in wort and the results were undesirable, but it certainly didn't do "nothing". It seemed to coagulate all the protein in the wort and it was just not very pleastant.

I've still got a small sample of the yeast that I collected from the fermenter after making this trial batch. I really should make some more.

As for how I made a large enough culture of the kombucha yeast here was what I did as best as I can remember:

I made a regular batch of fresh kombucha tea with white sugar.
Instead of fermenting at room temperature I placed a brew belt around it while it was brewing and warmed it up to around 85F. This favours the yeast activity in the Kombucha and allows the yeast to become more dominant over the other bacterias in kombucha. I bottled up the kombucha after a week and it was delicious. I saved the yeasty sediment from the bottom of the jar and placed that onto a stir plate with 2 liters of starter OG 0.02 and also placed the brew belt around that to again favour the yeast. I waited a few days and then placed that into the fridge and allowed the yeast to settle out. I collected the yeast sediment and pitched it into a one gallon batch of nearly unhopped pale wort and fermented at room temperature(if I recall). Yummy.

 

[Braumeise]

It might be that the wort is lacking Nitrogen. At least that is what I was told when starting making my own Kombucha, that the Kombucha needs the Nitrogen from the Tea to transform the Proteins...

I might be wrong though, never checked it, just brewed very strong tea (as I was told because of the Nitrogen saturation in strong tea).

 

[Thedillestpickle]

It might be that the wort is lacking Nitrogen. At least that is what I was told when starting making my own Kombucha, that the Kombucha needs the Nitrogen from the Tea to transform the Proteins...

I might be wrong though, never checked it, just brewed very strong tea (as I was told because of the Nitrogen saturation in strong tea).

Actually tea compared to wort will have very little nitrogen.

Wort is loaded with nitrogen.

Nitrogen in this sense actually means protein. Proteins are made up of amino acids which have a nitrogen molecule as the backbone building block. The reason micro-organisms need nitrogen is so that they can synthesize proteins, and in beer, the nitrogen comes in the form of amino acids.

This is relevant to gardening as well. If you want high nitrogen compost you need to start with high(but not too high or you will breed nasty bacteria) protein material. The proteins will be broken down through decomposition and the nitrogen will be released into the soil.

I was thinking about this. I've just started making kombucha and making bigger batches and love the tart flavor. Now that I'm trying my hand at sour's and not having easy access to liquid sour starters I've been looking at different things to sour the beer with. I've already started using sourdough but I also want to make a batch using kombucha. Did you just harvest the yeast from the bottom of your kombucha? How did you build it up to something that you could use in a brew?

It's an interesting way to make a beer, and the yeast characteristics(in my kombucha at least) are quite acceptable. If you have similar results to mine I don't think you will notice any souring. It really appears that by some sort of magic I now have a pure culture of Saccharomyces cerevisiae. There may be other organisms working the wort but I think they get suppressed by the vigor of this particular yeast strain. The souring in kombucha is typically produced by an aerobic organism. You may be able to age the beer for many months in a plastic fermenter to allow for some oxygen to slowly reach the beer. If the aceto-bacteria survive primary they may form a thin pellicle and add some sour. It won't be the same sour you typically encounter in beer which is lactic acid, but if you like the tart you may find the results favourable, especially if you can bottle up the beer and stall the aceto-bacteria before they completely acidify the beer. I'm sure there is a way to make something really tasty.

 

[Thedillestpickle]

So the 5 gallon batch has been brewed. That was about a week ago and it finished out primary ferment in about 3 days.

Unfortunately it appears this yeast is fairly underattenuative so I now have 5 gallons of beer sitting at FG 1.018.
That's just unacceptable for a beer that started at 1.060 OG

Ok so I pitched a pack of US-05 to the beer and I'm hoping that will do something, but it has been 24 hours now and I don't see anything happening.

I'm hoping this thread will have at least a little bit of traffic because I would like anyone with experience repitching underattenuated beers to let me know what they think. I realized after pitching the dry yeast that I probably should have at least hydrated it first. So does anyone think it might take off? My thinking is that the moment it hydrated in the roughly 4% alcohol of the beer it probably died.

Now I am also willing to hydrate another pack and pitch that to try to bring the FG down some more, however I am also wondering if anyone knows whether that will start to add a residual yeasty flavour to the beer? At that point there would be quite a lot of yeast in the beer.

I really enjoyed the flavour of the sample I took to test gravity. I think I will brew this again using some belgian candy sugar to make up 30% of the OG, as well as mashing for 2 hours at 148F, as well as waiting until the primary begins to slow before cranking up the heat to give it a final boost to finish. My goal would be to come out at under 1.010.

I also have some of this yeast streaked to agar and all the colonies look very similar, which is kinda neat. I suppose I will select one of those and streak another plate. If anyone can share some insight into yeast strain isolation please do. I don't really know anything about it. Some good reading material would be appreciated.

 

[tarmenel]

Give this a read: http://bootlegbiology.com/diy/

As for the us05 give it some time. I've also had no airlock activity and after two weeks was surprised to find the yeast had done the job. Be patient and let it ride

 

[Thedillestpickle]

I supect your air-lock wasn't installed correctly. I don't buy into the "don't trust your airlock" school of thought. If you have a good seal on a glass carboy and the water in the airlock is topped up to the right level and the floater is not stuck to the plastic you 100% of the time will see airlock activity when CO2 is being produced.

The airlock is not moving
I think pitching dry yeast into 4% alcohol is probably a bad idea. I Wonder how much sugar the yeast are even going to be able to chew on. I don't really want to drink 1.018 beer so I'm going to repitch another pack in a day or so.

 

[Thedillestpickle]

I rehydrated some yeast in warm water and got it bubbling again... It bubbled a lot so I'm sure the FG has fallen quite a bit. I haven't taken a reading because I don't want to add any extra oxygen but I will be bottling tomorrow so I'll find though then.

I'm pretty excited to find out how this turned out. I used the exact same recipe to brew a Saison with Beglian saison yeast... It's my best beer to date and I'm drinking faster than I normally do. Hopefully this komucha yeast/US-05 batch can hold its own against the belgian yeast. In the future I think I will brew this again but I will want to find ways to increase fermentability so that I don't have to repitch... that just seems unauthentic to me.

 

[BrewDawg79]

Any updates on this? Did you reach a stable fg? How is it tasting?

 

[Thedillestpickle]

Actually yes, sorry for not updating.

It was only a small batch so it was disappeared rather quickly.

I really liked it. Nothing really to compare it to in flavour, very unique, but not at all unpleasant and rather refreshing for a beer.

I am so busy these days that I have completely had to put brewing on the back burner but I have a sample of the yeast stored on an agar plate. I'm working hard to create time so that i can brew again. Probably something a little more generic like a brown ale, and then I'll make sure to make another batch of this recipe and work as many variables as I can so that i can hit a lower FG without using additional yeast.