How do they make dry ice would think that would be one use for co2 .
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Fermenting Under Pressure
- Thread starter wobbly
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Pretty sure I put a link in where the NASA technician who is also a home brewer made dry ice from CO2 it is what they will be doing on Mars for water I believe. There is also a test plant for making petrol from CO2, but the costs outweighed the returns.
Chris White having a chat about pressure fermenting.
http://beersmith.com/blog/2018/01/1...s-white-john-blichmann-beersmith-podcast-163/
http://beersmith.com/blog/2018/01/1...s-white-john-blichmann-beersmith-podcast-163/
Im currently doing my first pressure ferment which is a 14 litre Lager fermented with Saflager W-34/70 .(picture attached).
I have the fermenting corny attached to a corny that im going to have as the serving keg and that has the spunding valve attached.
It has been fermenting for 7 days and has reduced from OG 1044 to SG 1014.
Temp was 15C until pressure reached 15psi and then temp was increased to 18C.
I had my first taste and I can taste and smell the yeast which has a slight banana smell and taste.
Couple of questions.
Being pressure fermented I would have thought it would have suppressed the esters?
Would the esters have been produced due to too much early fermentation happening before having both cornies pressurised to 15psi?
As im going to be transfering to the 2nd corny, which is filled with the CO2 produced by the yeast, will I get this smell with every beer I pour?
On a side note the flavour from the yeast compliments the beer.
Thanks for any feedback.
Cheers
Shadime
I have the fermenting corny attached to a corny that im going to have as the serving keg and that has the spunding valve attached.
It has been fermenting for 7 days and has reduced from OG 1044 to SG 1014.
Temp was 15C until pressure reached 15psi and then temp was increased to 18C.
I had my first taste and I can taste and smell the yeast which has a slight banana smell and taste.
Couple of questions.
Being pressure fermented I would have thought it would have suppressed the esters?
Would the esters have been produced due to too much early fermentation happening before having both cornies pressurised to 15psi?
As im going to be transfering to the 2nd corny, which is filled with the CO2 produced by the yeast, will I get this smell with every beer I pour?
On a side note the flavour from the yeast compliments the beer.
Thanks for any feedback.
Cheers
Shadime
Attachments
It only happens on the Saccharomyces cerevisiae not so much on lager yeast, if you kept the 2nd corny flushing throughout the fermentation you should't get the smell of the CO2. A lot of the sulphur compounds should have been driven off .
I rehydrated the whole packet
Dan Pratt
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1 packet for a lager, is not enough. I typically would use that yeast W34/70 for a keg filler beer fermented at 15c using about 6g per L dry hopping to compete with the esters it throws off. Then use that yeast cake to make my lagers/helles or pilsners always targetting about 800 billion yeast cells for a nice cold 9c fermentation.
To suppress the esters for a lager yeast its been said that > 25psi is the pressure required to achieve that outcome.
Id suggest you now LAGER the beer you have made in the keg in the fridge for 30days and try it again, then if its still high on esters make a decision on the beer.
slcmorro
87 Warning Points. Bad Boy!
Disagree 110%. I've done several at 15psi and they've turned out great.
+1
You can listen to Beersmith #163 - Pressure fermentation with Chris White and John Blichmann. They had done several experiment with different pressure on lager, ideal pressure is 15psi.
slcmorro
87 Warning Points. Bad Boy!
Not entirely sure about that either. Mr Malty says for a 14L batch of 1.044 beer as per the OPs statement, 1.1 packs of 11.5gm of dry yeast is required.
Sure, more yeast is definitely better in most cases but considering he fermented at 15c I'd hazard a guess that the cell count made up for that .1 rather quickly.
But a more idealer pressure is no pressure at all, the judges could tell the difference along with Chris White that a Lager is a Lager, but in saying that I will be making a Faux Lager at 15 psi, and I know I will tell the difference but it could be nice.
This is what i used to determine the pressure.
Thanks all for your ideas, will try 2 packets yeast next time.
Will report back once it is transferred and chilled.
One other thing that I thought of is that the spunding valve i used was a PITA and the pressure fluctuated between 10-20 PSI so that may have played a part.
Cheers
Shadime
Here is another podcast you may find useful.
crazy thought coming...
if you pressure ferment PFK and daisy chain to a full corny as a empty co2 / blow off and capture the c02.
Then when you push the beer out of the PFK you...pushed water down the "out" dip tube of your blow off keg forcing the co2 out the "in" back into the PFV pushing the beer to the "drinking keg"
saves the co2 from your tank...
how much o2 would be in the blow off keg? i assume it mixes as it would be under pressure ?
may be crazy????
if you pressure ferment PFK and daisy chain to a full corny as a empty co2 / blow off and capture the c02.
Then when you push the beer out of the PFK you...pushed water down the "out" dip tube of your blow off keg forcing the co2 out the "in" back into the PFV pushing the beer to the "drinking keg"
saves the co2 from your tank...
how much o2 would be in the blow off keg? i assume it mixes as it would be under pressure ?
may be crazy????
I have done this with my pressure ferment cubes, its easy to compress gas using water (mains about 70psi) my worry was the oxygen in the water mixing with the CO2 but I drank the beer within 2 weeks with no noticeable oxidisation.
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interesting, i would have thought the co2 from the ferment would have a more co2 / o2 mix. but i got NFI really
i probs will just continue to push it with co2 out of PVK but was something i thought about while reading the new parts of the thread
Considering the yeast may take up the oxygen there should be no O2 coming out look I think it is a good idea but really needs someone more qualified to validate the idea.
Maybe slightly OT, but I've just done a 28L 1.040 batch and set to 15PSI, in 40 odd hours since pitching W34/70 (15g) it has dropped to 11PSI and is sitting at this ATM... Krausen has settled alot as well. An identical gravity-brewed batch would have Krausen hanging around for three days at least... It fermentation slowing down or have I killed the yeast?
I don't have temp control but Melb weather has been fairly stable and the brew is well insulated.
I don't have temp control but Melb weather has been fairly stable and the brew is well insulated.
I don't think the yeast like it, I did a stout last brew and applied to much pressure I believe, looked to be finished but 24 hours after dropping the pressure off fermentation started again and dropped 4 points more. It definitely suppresses the krausen though.
Weal, yeah I had that suspicion - so I've gradually built up the pressure so the yeast can adjust... I'll also slowly reduce the pressure once this batch is kegged so I can re-use these yeasties.
Odd that the common perception is pressure brewing is meant speed up the process - but it seems to be the opposite as the yeast is suppressed?
Earlier post on this thread suggests that W34/70 (and other strains) had no issues at much higher 21PSI, and reading other resources I thought around 15PSI would be the happy medium? Well, we'll see how it turns out
Odd that the common perception is pressure brewing is meant speed up the process - but it seems to be the opposite as the yeast is suppressed?
Earlier post on this thread suggests that W34/70 (and other strains) had no issues at much higher 21PSI, and reading other resources I thought around 15PSI would be the happy medium? Well, we'll see how it turns out
What are you brewing, and did you watch the podcast I put up on the bulk buy thread? WLP 925 for a lager yeast at one Bar.
Weal, it's a lager-like brew, partial BIAB: Pale Ale Malt 1.5kg + 1kg Munich + Caraaroma 100g & Hallertau MF late in boil.
Plus Coopers Lager Can. I'm yet to go full AG so I've been doing half BIAB / half can for now...
I've been using dry Yeasts so I went with something familiar so I can suss out the whole pressure ferment process
I'll have another look at the podcast to understand it a bit better.
Plus Coopers Lager Can. I'm yet to go full AG so I've been doing half BIAB / half can for now...
I've been using dry Yeasts so I went with something familiar so I can suss out the whole pressure ferment process
I'll have another look at the podcast to understand it a bit better.
droid
somewhere on the slippery slope with a beer in han
1.040OG ? it could be done, what's your expected FG?
15PSI is no problem, I brew all mine at 15PSI and once the pressure drops it's done. 1.040 is around the gravity you might use for a yeast starter and with the right amount of yeast 40hours, especially under pressure could be enough. If you had been fermenting at 9C this time-frame could be a problem but if at ambient 22 or something then yeah.
Can't comment on the resulting taste of 34/70 at that temp tho
Hey Droid, the projected FG is 1.009, I'll check it later today (72hours after pitching);
I always hydrate the yeast, and this one was a quick starter as usual (20deg wort) - active visible ferment within four hours but geez this is QUICK if it has infact chewed through all the fermentables! The pressure's been sitting at 8PSI since yesterday.
I always hydrate the yeast, and this one was a quick starter as usual (20deg wort) - active visible ferment within four hours but geez this is QUICK if it has infact chewed through all the fermentables! The pressure's been sitting at 8PSI since yesterday.
Hey Weal, my super-accurate (and calibrated!) eBay refractometer read @ 1.016 on Saturday. So in real terms, considering the correction factor it could well be done fermenting by now.
The pressure has also dropped to 2PSI (I'm assuming absorbed by the brew?) and is staying on that since sampling - I wasn't sure if it was meant to be maintained constant through the fermentation?
I'll let it sit for for a couple more days, keg and force carb it. If it's a stuff up - lesson learnt. But smelling the sample it seemed ok.
I'm looking to re-use this yeast too.
The pressure has also dropped to 2PSI (I'm assuming absorbed by the brew?) and is staying on that since sampling - I wasn't sure if it was meant to be maintained constant through the fermentation?
I'll let it sit for for a couple more days, keg and force carb it. If it's a stuff up - lesson learnt. But smelling the sample it seemed ok.
I'm looking to re-use this yeast too.
I presume you are doing this in your Fermentasaurus, are you dropping the pressure or is it dropping by itself?
