How to Open ferment?

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jceg316

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I want to try an open fermentation with Ebbegarden, a really flavourful kveik yeast, however I have suffered from infected batches at the best of times. What's the safest way to do an open fermentation? Ebbegarden ferments in about 5 days at 35°C.
 
Its meant to increase esters.

I have open fermented before by just laying the lid on top and covering it with a bin bag to keep out dust. Put an airlock on as fermentation starts to end.
I have a fermentation chamber, will need to give it a clean as well. Do you sterilise the inside of the bin bag?
 
however I have suffered from infected batches at the best of times.
Wow that sounds super unlucky. To have had multiple spoilt beers due to infections... Hmm are you certain that they have had infections?. Have you left the beer for long enough to fully mature? Are you following a strict clean and sanitise routine? Your fermentation chamber should be a clean enough environment to just leave the lid off of your FV.
 
I always cover my open fermentation with a wet (water and disinfectant) cheesecloth to start. This makes diffusion of gases possible, but keeps out larger things like dust and what rides on dust.

This also makes it possible to have a quick peek at the fermentation. When the krausen subsides, but fermentation still going on (let's say 75% of the way), I rack to a closed fermenter to finish the fermentation.

Since previous summer, I have done 6 such fermentations, with good results, and no contamination.
 
Thanks for your advice everyone! Will let you know how my beer turns out.

Wow that sounds super unlucky. To have had multiple spoilt beers due to infections... Hmm are you certain that they have had infections?. Have you left the beer for long enough to fully mature? Are you following a strict clean and sanitise routine? Your fermentation chamber should be a clean enough environment to just leave the lid off of your FV.
I had a thread about this a while ago, basically my Grainfather recirculation pipe was not clean and it infected a lot of batches before I figured out what was going on. I recently took it apart again for a clean and there were loads of grains inside which aren't coming out. I have the Grainfather cleaner but doesn't seem to actually clean anything.

I have a 50 litre HERMS and for my next brew I'll mash and sparge in the GF then pump the wort to my other kettle for the boil.
 
I agree with @chthon. I've never done an open ferment beer, but I used make loads of wine and I always did the first week of fermentation in a plastic bucket with a clean tea towel tied over the top, not even wet, before straining into demijohns. I think, if I did it with beer, I'd use a yeast that produced a big rocky head like West Yorkshire, and, even then, put the lid loosely in place until the head had formed. Some of these old English (and presumably farmhouse) yeasts have been selected over the decades for their suitability to open fermentation in, say, Yorkshire squares. It should be remembered, too, that there isn't the variety of airborne infections that you would find in your house or kitchen from other foodstuffs, mould spores, cat's puke and grubby-fingered, 'orrible little mingers that like to poke their dripping noses into everything.
 
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Its meant to increase esters.

I have open fermented before by just laying the lid on top and covering it with a bin bag to keep out dust. Put an airlock on as fermentation starts to end.
Why would it increase esters since traditionally the beer is blanketed with a foamy head and drawn off from under the head before the head subsides into the beer? Not contradicting you, I'm genuinely interested. The couple of times I used West Yorkshire Ale yeast, I had so much foam and froth blowing over that I wish I had left the lid off and I'm pretty sure this yeast comes from an open fermentation system. But I'm not sure that it hasn't been selected for its enduring head (which protects the beer) rather than any flavour difference. Any pointers in this direction would be gratefully received.
 
Thanks for your advice everyone! Will let you know how my beer turns out.


I had a thread about this a while ago, basically my Grainfather recirculation pipe was not clean and it infected a lot of batches before I figured out what was going on. I recently took it apart again for a clean and there were loads of grains inside which aren't coming out. I have the Grainfather cleaner but doesn't seem to actually clean anything.

I have a 50 litre HERMS and for my next brew I'll mash and sparge in the GF then pump the wort to my other kettle for the boil.
Oh right I see. Well at least you got to the heart of the issue. I was tempted to order you a voodoo priestess to come and cleanse your brewing space🤣
Nice one. Good luck with the open fermentation 👍
 
Why would it increase esters since traditionally the beer is blanketed with a foamy head and drawn off from under the head before the head subsides into the beer? Not contradicting you, I'm genuinely interested. The couple of times I used West Yorkshire Ale yeast, I had so much foam and froth blowing over that I wish I had left the lid off and I'm pretty sure this yeast comes from an open fermentation system. But I'm not sure that it hasn't been selected for its enduring head (which protects the beer) rather than any flavour difference. Any pointers in this direction would be gratefully received.
CO2 levels in wort, decrease ester production. In closed cylindrical fv's CO2 saturation is higher do to reduced off gasing, partly due to the relationship between volume and surface area, but also back pressure within the headspace.

Just opening an fv is only a small part of it. Fermenter geometry plays a significant part with cylindrical fvs also recirculating co2 back into the wort, IIRC.

There's other advantages/disadvantages to open fermentation such as volatiles such as sulphur don't get reabsorbed. This also means hop volatiles are lost to a greater degree.
 
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I always cover my open fermentation with a wet (water and disinfectant) cheesecloth to start. This makes diffusion of gases possible, but keeps out larger things like dust and what rides on dust.

This also makes it possible to have a quick peek at the fermentation. When the krausen subsides, but fermentation still going on (let's say 75% of the way), I rack to a closed fermenter to finish the fermentation.

Since previous summer, I have done 6 such fermentations, with good results, and no contamination.
That'll make an interesting night for the OP, with seeing reports of kvieks fermenting out within 24 hours. Best put a bed next to the fv. :laugh8:
 
Why would it increase esters since traditionally the beer is blanketed with a foamy head and drawn off from under the head before the head subsides into the beer? Not contradicting you, I'm genuinely interested. The couple of times I used West Yorkshire Ale yeast, I had so much foam and froth blowing over that I wish I had left the lid off and I'm pretty sure this yeast comes from an open fermentation system. But I'm not sure that it hasn't been selected for its enduring head (which protects the beer) rather than any flavour difference. Any pointers in this direction would be gratefully received.

Fermenting under pressure reduces esters. Even an fv is pressurised a little. I presume it was easier to top crop back in the days in open tanks. I think the co2 blanket has somewhat been debunked but i could be wrong.
 
Hm, about doing an open fermentation increasing esters: my experience since last year with open fermentation is that the resulting ones are some of the cleanest beers that I brewed. I sometimes get the impression that a bit more esters would give them a bit more character.
 
Its meant to increase esters.

I have open fermented before by just laying the lid on top and covering it with a bin bag to keep out dust. Put an airlock on as fermentation starts to end.
This. is pretty much what I do, and I only use kveik yeast. Maintain the high temperature for the first 48h then start reducing. I step crash down to room temp 5-7 degrees C a time to retain as much of the ester profile as possible.

Also there are alternatives to using a fermentation chamber- I do mine using sanitised buckets sitting in basins of water that's had a reasonable dose of thin bleach and is heated with an aquarium heater.
 
One thing I forgot to add, and I don't know if this is just a kveik thing or a general beer thing, so forgive me if I'm stating the obvious. After the krausen drops the CO2 blanket really seems to loose its effectiveness. I cover mine with sanitised clingfilm as soon as I've top cropped the yeast, and bottle as soon as I can.

I've lost batches due to contamination, and with one exception they were ones I had to leave in open primary longer than I otherwise would have. Acetobacter every time. I have some other ferments on the go and live near whisky bonds and businesses that deal with old whisky barrels, so I have to be really careful. Maybe your local microbiota are a bit more forgiving!
 
RE:- EarthKveik I agree the more wine/beer you make the bigger the magnet for the bad guys,Therefore the more careful you need to be.

When i go on a winemaking roll the fruit flies start to appear from "nowhere" after a few brews.
 
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