34/70 pressure fermenting

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Cheyne_brewer

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I’ve got an AG Pilsner fermenting under 12psi pressure with 34/70 at 20C. Attenuation rate seems to be very similar to fermenting at the recommended 12-15C so no great advantage.

From your experiences how high can I push the temperature and still have a clean result?
 
I did a split batch with the W34/70 at one bar at 24c against 0 bar and 10c. The pressure fermented one was still very clean and actually better in taste than the 10c one ... BUT the pressure fermentation took two days longer :laugh8:
 
I always do 15psi at 20 - 24C and its finished fermenting and cleaning after 7 days, The pressure just stops the esters I think. I thought it took three weeks at 12C to ferment to <1.009, I don't know as I have only ever done pressure brewing as the amount of time put me off. Have you read this:
https://brulosophy.com/2016/02/08/f...ager-yeast-saflager-3470-exbeeriment-results/This was not under pressure but He says that after 1 week the cool ferment was at 1.032 SG and the warm ferment was 1.009. I suppose the pressure would stress the yeast a bit so it wouldn't go that fast but it's supposed to stop the ester/ale flavours.
 
Not with pressure, but you may be interested in this Fermentis article on how far you can push 34/70
https://fermentis.com/en/news/fermentation/rediscover-saflager-w-34-70/
Here at least, they seem to have broken the links to the images, but I copied them a while ago to this post in the HBT warm-fermented lager thread, which may also be of general interest :
https://www.homebrewtalk.com/threads/warm-fermented-lager-thread.592169/page-34#post-8875435
There's also a podcast about the same study here if that's your thang : Profiling 34/70
 
Thanks for the info. My observations from the behaviour of this current batch are that although it may tolerate higher temperature and pressure the only advantage is not needing to keep it so chilled in warm weather. 34/70 is the only true lager yeast I’ve used, it seems to have a single rate of attenuation no matter what you do to it!
 
How did you get on with it? I've just ordered this for a rice lager. I'd much rather do it under pressure and not have to worry about the temperatures much.
 
I regularly brew lagers and pilsners at 24degC (76F) at 15PSI in 60litre batches, it finishes after 4 days and then leave for another 3days before crashing.. Last batch was 1.045 and put 56litres into the PET Apollo (60litres snub nose) at 24 degC from counter-flow chiller with two packs of 34/70. 12 hours later really active and after 7 days crashed for 3 days and kegged under pressure and FG was 1.007. I did add some gelatin solution in fermenter at 7 days under pressure as I crashed. Could drink immediately but better after a week in corneys at 2degC. Gives me exactly 3 corneys full. have used with Maize and rice and all come out great. two packs of yeast has always been enough.
 
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I'm a 34/70 fan. Before I used it I thought that if you ferment at 13c its going to be slow but its not. 34/70 at 13 is like an ale yeast at 19. I've never pushed it higher in the early stages of fermentation but I do increment it to 18 before chilling and/or packaging.
 
I'm a 34/70 fan. Before I used it I thought that if you ferment at 13c its going to be slow but its not. 34/70 at 13 is like an ale yeast at 19. I've never pushed it higher in the early stages of fermentation but I do increment it to 18 before chilling and/or packaging.
I have only used this yeast under pressure and Fermentis say it's a neutral yeast. That way I know that if I play with grains and hops it's them that is changing the characteristics. I'm more of an experimentalist now and again and have regular favourites now after finding my best combos.
 
I’ve got an AG Pilsner fermenting under 12psi pressure with 34/70 at 20C. Attenuation rate seems to be very similar to fermenting at the recommended 12-15C so no great advantage.

From your experiences how high can I push the temperature and still have a clean result?

From "Your Lager can take the pressure"
Matt Winans, research and development scientist at Imperial Yeast, says they’ve had successful lager fermentations at or below 1 bar (14.5 psi). He recommends the popular 34/70 lager yeast—Imperial’s strain of it is L13 Global—because “it keeps good vitality and viability under pressure, and [it] maintains the great fermentation profile it’s known for.”

Lots of great detail in the full article sourced from commercial lager brewers who use pressure fermentation, and yeast company testing.
HTH
 

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