Fermenting with co2

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I don't understand the question! Sorry. :?:

As fermentation of sugar by using yeast produces a load of CO2 it would be impossible to ferment without CO2.

However, if you mean "carbonating a keg using fermentation" as opposed to "carbonating a keg using CO2" then it's a common practice; and one that will become much more prevalent if the CO2 shortage continues! :thumb:
 
Personally, I've never done it but I can see no reason why a Corny Keg wouldn't work as an FV.

However, I reckon that it would be difficult to transfer the brew after fermentation due to the depth of the trub, an absolute bugger to clean with such a narrow top and the tall and narrow construction would probably result in an active krausen deciding to go walkabout.

I have to ask "Why would you want to use a Corny Keg as an FV anyway?" :?:
 
Hi brewers

I asked the same question recently but didn't get a reply. Again it was hard to describe what you want to know about!
I assume you want to add an aprv ( adjustable pressure release valve) to allow the c02 to keep pressure at certain level to help with fermentation? I searched with "spunding" which threw out some info but still not sure what to do. So will be interested if you get any more info.

C
 
I watched a podcast with Blichman and Brad Smith doing exactly this,they had 3 beers pitched with the same yeast,the one with the blanket of co2 fermented quicker than the other beers,and a noticeable difference in the finished beer
 
… I have to ask "Why would you want to use a Corny Keg as an FV anyway?" :?:

Ooooo….. I know the answer to that one! From a conversation earlier today ...

My next low-alcohol brew is planned and it will use "London ESB" yeast (the "Windsor" I had is 6 months beyond "best-before" date). I've taken note of your hop list and got 200g Bobeks (mainly copper hops) and 200g Wai-iti (mainly for dry hops) for a 40L batch (couldn't get Riwaka). I'm using whole hops because my copper isn't geared up for pellets and the pellets were all 2016 stock anyway. 1Kg of grain in 40L, split equally between Lt. Munich, Caramalt, Light Crystal and Wheat Malt (no Pale, they'll all self-convert or just need steeping). 0.5ABV, 35IBU … ish. No limes for this "Big Drop Pale" clone attempt - I'm happy with the suggestion that Wai-iti has lime-like notes. Perhaps 250g Lactose.

Should be different from the Nanny State clone. Mash 40 mins at 69C (5L water), very minimal (no?) sparge, Top-up and boil for 30 mins, most Bobeks for full duration, some for 5 mins, some steeped. Ferment in serving containers (Corny kegs) under 12-15psi pressure with dry hops. Remove dry hop baskets and re-pressure. Should be drinkable after 7-10 days. It's fun coming up with these minimalist methods for churning out low-alcohol stuff.

No trub issues, no complicated transfers.

To control the CO2 from fermentation I'm using secondary regulators as "spunding" valves (Shako NR200s), further smudging the boundary between fermenter and keg.
 
I watched a podcast with Blichman and Brad Smith doing exactly this,they had 3 beers pitched with the same yeast,the one with the blanket of co2 fermented quicker than the other beers,and a noticeable difference in the finished beer

Ah, "spunding"! (The name always reminds me of The Sex Pistols!)

Sorry, but I can't help you there. "Spunding" looks to be yet another system that is trying to discover the current Brewing Holy Grail of speeding up the fermentation process.

It may be very relevant to speeding up a commercial process, but personally it's not something that I am trying to do.

With regard to the "noticeable difference in the finished beer", maybe it still tasted awful but it tasted less awful than the other two!

Enjoy. :thumb:
 
............

No trub issues, no complicated transfers.

............

Surely, if you are fermenting a wort you will produce a load of yeast cells which then die off, fall to the bottom of the FV (be it a traditional FV or a Corny Keg) and form "trub".

How many pints do you expect to lose (or how many weeks do you expect to wait) before the tube that goes to the bottom of the Corny Keg (where it sits in the trub formed by the dead yeast cells) produces a non-cloudy beer? :?:

Still not convinced. Sorry! :thumb:
 
Nanny State clone undergoing fermentation. The "relieving" mechanisms in those NR200s is so much better than those "adjustable PRVs". The snag with them is I haven't figured how to detach them from the CO2 cylinder and have them hold pressure (the attached cylinder isn't supplying any CO2, its just providing "back pressure").
20180322_134005_WEB.jpg
 
Surely, if you are fermenting a wort you will produce a load of yeast cells which then die off, fall to the bottom of the FV (be it a traditional FV or a Corny Keg) and form "trub".

How many pints do you expect to lose (or how many weeks do you expect to wait) before the tube that goes to the bottom of the Corny Keg (where it sits in the trub formed by the dead yeast cells) produces a non-cloudy beer? :?:

Still not convinced. Sorry! :thumb:
I was only using my experiences to answer your question, not suggesting the others ferment in Corny kegs for the same reasons. But to answer these new questions: How many pints do I expect to lose? A: None. How many weeks do I expect to wait? A: I've waited ONE week for the fermentation to finish, I'm not waiting any longer. I do use floating extractors in the kegs (extracting from the surface, not the bottom) but, to whack the ball back into your court, how much yeast do you think an OG1.007 beer creates?
 
Most yeast will become stressed at 7 psi, they will also become stressed having dissolved co2 in the wort, don't pressurise ale yeasts until the last 1 or 2 degrees plato. The yeast that they used in that video was WLP 925 which is a lager yeast and can perform at 15 psi, but all the beer judges could pick the difference between the faux lager produced at higher fermentation and the application of pressure using the WLP 925 and a conventional lager yeast and lower temperatures at a longer time.
The whole idea started when Terri Fahrendorf printed this PDF, its been taken well out of context now, I cant wait for someone in USA starting a thread about boiling in a pressure cooker, that would be a laugh
http://www.terifahrendorf.com/Closed-Pressurized-Fermenatation.pdf
 
Yep. I've done this, two ways. The first with an ale, where I pitched the yeast,then add a spunding valve to the psi required to carbonate beer at my fermentation temperature, say 18c at 16 Psi. As the wort ferments, the pressure builds and carbonates the beer. Trub isn't really an issue as you can either use a shortened dip tube and transfer the final beer to a serving keg, or just use your normal dip tube and discard the first pours where the trub gets pulled out first. The second way was brewing a Lager, where I set the top pressure to 5 Psi. Fermenting under pressure reduces esters giving a cleaner beer and allows you to ferment faster at higher temperatures, with the similar effect as fermenting cooler, although I just fermented at 12c. A real benefit for brewing good lager.

In essence it is no different to bottle or cask conditioning, which doesn't kill yeast or add off flavours.

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Thank you all for your input,and the reasons for asking this question was simply based on having the benefit of an enclosed environment with no oxidisation issues,and thinking should I have a go? would the finished product be considerably better?

Video link if interested

 
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............. how much yeast do you think an OG1.007 beer creates?

Sorry but I nodded off! Old age!

My answer is "Just enough to make the beer cloudy for as many pints as it takes to clear." I know drinking cloudy beer will do me no harm but I don't actually brew it to be cloudy.

Also, I agree with "foxy" above even though I haven't a clue what he is talking about (Plato being a Greek philosopher) but I can see absolutely no merit in a Homebrewer attempting to produce something identical to that which a commercial company produces.

When I started drinking beer the pubs served it from wooden barrels at cellar temperatures. Occasionally you got a cloudy pint and occasionally a barrel went "off" before it was emptied; but even at about 1/6d a pint (7.5p in today's money) the Breweries made a profit without forcing us to drink the over-carbonated frozen brews that they currently sell.

Happy Days! :thumb:
 
I only brew ales,never made lager,and don’t drink it either.I brew old style bitters and pale ales,and some dark ales,but I do like an experiment now and again.
 
Thank you all for your input,and the reasons for asking this question was simply based on having the benefit of an enclosed environment with no oxidisation issues,and thinking should I have a go? would the finished product be considerably better?
Some of the best ales are fermented in "open" systems. But home-brewing was likewise done in "open" systems (a bucket), and most people these days use a "closed" system (airlock) and are being rewarded with less risky brewing.

So to answer your question: Not necessarily. Depending what you brew some beers are not going to be considerably better, or even just better. Brewing totally enclosed with slight positive CO2 pressure (to negate the effect of the smallest leak) might well produce more consistent results. But removing risk leads to taken others: "Can't be bothered to bottle that batch just now - I'll do it next month", etc.
 
I only brew ales,never made lager,and don’t drink it either.I brew old style bitters and pale ales,and some dark ales,but I do like an experiment now and again.
Fermenting in a closed, pressurised system offers benefits for lagers or clean hoppy styles, where you want to limit oxidation and loss of hop volatiles. For bitters, etc. I probably wouldn't bother, the last thing I want to be doing with British Ale yeasts is reducing the ester profile.

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… When I started drinking beer the pubs served it from wooden barrels at cellar temperatures. Occasionally you got a cloudy pint and occasionally a barrel went "off" before it was emptied; but even at about 1/6d a pint (7.5p in today's money) the Breweries made a profit without forcing us to drink the over-carbonated frozen brews that they currently sell. ...
No good arguing with me, I'm doing something kooky (brewing 0.5% beer) and when you're using only twice the sugar some people prime their kegs with (and less yeast), fermenting in the keg becomes very convenient. What "foxy" is going on about may be talking about what others are doing with "fermenting under pressure" - argue with them!

The age you are talking about I don't think anyone was brewing 0.5% beer. I'm obviously a right young tearaway - cider cost 1/- a pint in my day and as it wasn't taxed was much cheaper than beer. I remember in "The Rising Sun" at Botus Fleming buying two pints and the landlady returns with the cider... "Here's two halves, I'll not have you turning into one of those rabble in the back. That'll be 2/-." (yeah, we got charged for pints for having the cheek of asking for them, but other "services" were available...) "I'll give you 3d for that wart on your finger?".
 
I too brew small - mainly to reduce the Kcal intake!

The lowest yet has been two Pumpkin Ales:
  • Spiced:
    • OG 1.030
    • FG 1.010
    • ABV 2.7%
    • Kcal per Litre = 291Kcal/Litre
  • Golden:
    • OG 1.031
    • FG 1.011
    • ABV 2.63%
    • Kcal per Litre = 302Kcal/Litre
I still have six bottles of the Spiced left as I brewed it with too many cloves and expect it to mellow a bit by this Christmas.

For ordinary brews I am down to a 3.64kg grain bill for a Belgian Pale Ale that returned:
  • OG = 1.032
  • FG = 1.011
  • ABV = 2.76%
  • Kcal per Litre = 312Kcal/Litre
A beautiful taste and colour ...

IMG_0618.jpg


The only box on Brewersfriend that it didn't "tick" was the ABV!

When I restart I will probably drop the grain bill by another half kilo for another Pale Ale. :thumb:
 
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