Fermenting Under Pressure

[rude]

I know quite a few of the Yanks dry hop from the start with no ill effects & like you said, the ferments done & dusted relatively quickly.
I'm probably just going to pressure ferment then transfer to another keg & hook up the gas at this early stage. When I've got a few under my belt, I'll get a bit more adventurous & try a natural carbonation. I assume you know the ferment is finished once the gauge drops to 0.

The pressure shouldn't drop after ferment unless you cold crash it

I take samples as it ferments with a bronco tap & check in the hydrometer to see how the yeast has attenuated

Both times (only done 2 ) ferments with it the spunding valve hasn't released to the set 10 psi , gauge went all the way around
had to manually release the pressure back

Both beers were Kolsch the second pitched on top of the first & og 1050 fg 1010 there abouts so happy with attenuation
both beers came out really nice

On the buid 1V at the moment but cant wait to ferment in it again

 

[rude]

another yeast / pressure related question.

Is anyone pitching onto a yeast cake after a pressure ferment?

I have a yeast cake from US-05 used to brew a pale ale, still under 20Psi pressure about 1 week old at that has been sitting under 4C, hasn't had any oxygen contact since initial pitch. It was brewed at 10psi then capped with 5 points to go. 1.050 OG down to 1.012 FG. I'll be brewing a 1.073 IIPA. Is this viable?

The original beer was awesome, although I am slightly concerned that the yeast may be stressed from ramping the pressure to 20psi at the end of the first ferment, and is a 1.050 brew to high to reuse?

I have reused the yeast straight on top of the cake ,this beer was slightly better than the first
but was slightly diff grain bill

 

[pirateagenda]

I'm leaning towards giving it a shot, but really don't want to wreck this batch as there is a LOT of hops going in!

On another note, did an all citra version of Dr Smurto's Golden Ale, with 2g/l dry hopped as my last pressure ferment and it was sensational. The best beer I have made by far and has to be up there as one of the best I've tasted! Fermented under 10PSI pressure until a bit over 5 points to go, dry hopped, c02 added to repressure, spunding valve taken off at that point to cap the fermentation, left for 4 days, transferred to kegs with 20PSI into fermenter and slightly less in receiving keg / bled very slowly, drank the next day and carbonation was spot on. Hop aroma and flavour was very present for only 2g/litre dry hop. The first keg was dry in 2 nights with 3 drinkers.

 

[Mardoo]

The original beer was awesome, although I am slightly concerned that the yeast may be stressed from ramping the pressure to 20psi at the end of the first ferment, and is a 1.050 brew to high to reuse?

I've been doing some reading of a few papers on lab experiments on pressurised fermenting. Regarding reusing yeast, they say that they haven't seen a reduction in yeast health at the end of fermentation, however it MIGHT shorten the number of generations yeast is viable. However, there was nothing conclusive on that and it was proposed as a follow-up study.

I posted a TLR in the spunding valve thread, but I'll post the papers here since they're relevant. Basically stay under 20 PSI/138 KPA and you'll see few, if any issues.

Oh, and I've had nothing but success with very hoppy beers done under pressure. I just use low pressure, solely to ensure oxygen exclusion, but it's fantastic how much more hop presence there is.

View attachment CO2 Pressure and Ester and Fusel Formation.pdf
View attachment Controlling Yeast Fermentation.pdf
View attachment Improving Yeast Fermentation Performance.pdf
View attachment Yeast Response to Fermentation Under Pressure.pdf

 

[Lager Bloke]

I've used White Labs Kolsch/German Ale yeast around 4 times-did 1st pitch started in a litre of wort then next batch tipped straight onto yeast cake in FV.Once I'd keged 2nd brew,tipped remnants into glass flask and drained most of the remaining beer off yeast cake but didn't wash it from this stage.Have done another 2 batches with the same yeast-the 4th one I'm drinking now and there is no difference between any of the ones other than the slight changes to grains/hops.Have a new pack of yeast bought last week so maybe use it for next ferment-would like to think if I can get the 4 ferments out of 1 packet that's pretty good value,Rob.

 

[Hpal]

I've got some 34/70 that I've been reusing for probably a year. I just save some and keep it in the fridge then repitch it next brew, haven't taken note of how many times it's been reused but it performs awesome and no sulphur which I find first gen 34/70 can give a lot of.

 

[Coldspace]

Usually pitch my lagers onto the yeast cake in the kegmenters and all turn out sensational , better than the first gen batch. I usually only go one cake ferment, then dump and use new starters.

citra golden ales rock, done a few myself. 2 grms dry hop citra is just perfect with smurtos grain bill....

 

[trevgale]

I usually ferment under pressure going up to 20-25 psi prior to chilling. After I transfer the beer off the yeast I give the fermenter a bit of a shake and then transfer the yeast to a couple of sanitised 1.25L PET bottles with carbonation caps that have been CO2 flushed and pressurised. When I want to pitch I just transfer some slurry under pressure into the fermenter.

I believe this method minimises the chance for contamination and I have successfully used the same yeast for 10 generations storing for up to a month between brews. I have never had a problem with viability and the ferment kicks off as quick as if I had just used a starter. The yeast is stored under pressure which I know is not the best for it but I have not seen any issues.

Anyway based on my experiences I would not be worried about pressure fermentation damaging the yeast, at least not for WY2124 and WY1056 which are my usual strains.

 

[Lionman]

I picked up some cheap Chinese kegs and although advertised as 19L, they are actually 21L and don't fit in my keg fridge.

Instead of staring into the bottom of an empty pint glass, feeling sorry for myself I decided to try out pressure fermenting using them.

Here is a pacific ale ish beer happily fermenting away using WLP001, currently sitting around 20PSI at 21c.

Im using a minikeg to catch the blow off. Seems to be working well.

Hopefully I can fill a corny from it after pushing most of yeast and trub out.

I've set up the blow off tube so two kegs can vent into one minikeg in the future if I feel so inclined.

 

[rude]

Just wondering how everone is taking hydro samples
Im using beer out connect with a bronco tap
Found a line pressure calc spreadsheet & worked out I need 3.7 Metres long line 5mm ID
to pour a sample without too much foam a 39 psi 18c
Does this sound about right

 

[Danscraftbeer]

I just use 1mt hose on a disconnect and shoot into a 2lt jug then let it settle. Degas it then pour into the hydrometer.

 

[Mall]

Same, pressure fermenting has, according to my sampling pals, improved my beer a great deal.

 

[tugger]

I just go direct from the out with a tap.
I get a bit of foam but there is enough for a sample once settled.

 

[Lionman]

I just squirt a bit of foam in to a glass, it doesnt make much difference when you use a refractometer.

 

[Mall]

My setup, works well...

IMG_20170804_092212

• Mall
• 4/8/17

Pressure ferment

IMG_20170804_092205

• Mall
• 4/8/17

 

[cliffo]

Is that the spunding valve from ibrew?

Does it work well? I was considering building my own but if this one works fine then I might just buy this.

 

[Mall]

Yep, the ibrew version. It's OK but I think I could do better.

 

[Dae Tripper]

I just use 1mt hose on a disconnect and shoot into a 2lt jug then let it settle. Degas it then pour into the hydrometer.

Hey buddy, what is your degasing technique?

 

[rude]

I only had 2.5 M beer line left tried that but not much better than my short length
Took a sample this morning short length & just let it settle then poured more in
to get enough for a sample
I have been going straight into the hydro tube wait a few hours to degas while spinning
In all it works but a bit time consuming

 

[Danscraftbeer]

Hey buddy, what is your degasing technique?

Just swirl it in the jug a few times to release the carbonation. Warm beer goes flat pretty quick.