Fermenting Under Pressure

[rossbaker]

No. I don't like keeping beer on primary for too long, certainly not after ferment has finished and I'm dispensing. Pro of nc into corny and ferment/dispense from same is reduction of transfer, (oxygen, number of vessels, etc) but exposure to trub has the potential to negate those benefits.

Good stuff manticle. It was your attempt at nc and fermenting in a corny, and the thread that ensued that sent me down this path.

 

[manticle]

My brain cogs have started moving again.

 

[Mardoo]

Oh shit...

 

[Digga]

So I've just put 40L into a 45L keg, I don't yet have a spudding valve but am in the process of ordering one from amazon. I've rigged up a blow off tube attached to a gas disconnect.
Question is I'm going to dry hop with around 4 gravity points left before terminal. If I didn't reconnect the gas disconnect blow off tube would the pressure build too much (>20psi)?
What do you experienced pressure fermenters think would be the optimal stage for disconnection?
I'm fermenting an ale with Nottingham at 18c.

Thanks a bunch.

 

[Danscraftbeer]

So I've just put 40L into a 45L keg, I don't yet have a spudding valve but am in the process of ordering one from amazon. I've rigged up a blow off tube attached to a gas disconnect.
Question is I'm going to dry hop with around 4 gravity points left before terminal. If I didn't reconnect the gas disconnect blow off tube would the pressure build too much (>20psi)?
What do you experienced pressure fermenters think would be the optimal stage for disconnection?
I'm fermenting an ale with Nottingham at 18c.

Thanks a bunch.

I'd take a guess at disconnect at 1 point gravity but you really need a spunding valve to be sure etc. 4 points too much for 40lt. I've found even if it seems you reach final gravity it can still increase in pressure.

 

[Digga]

Thanks Dan, might just ferment out using the blowoff then pump 20 or so PSI in there and cold crash, this should negate negative pressure whilst chilling. looking into the spunding valves now and the amazon option is out the question with $70 in the cart and $45 in shipping!! that's for 2 setups...

 

[Danscraftbeer]

The Keg King ones work fine for me. $30 each I think. Plus higher rating gauges $7 each.

 

[Digga]

Think I'll just order a KK one for the time being then upgrade as required. I have seen others on here with success with them as well.

Thanks mate!

 

[Digga]

The Keg King ones work fine for me. $30 each I think. Plus higher rating gauges $7 each.

Dan

Can't seem to find the higher rated gauge on the website? Do you have a link as I'm just about to send the oder off.

I'll buy something off ebay if they don't have it.

Thanks

 

[Danscraftbeer]

No link sorry. I go to their local store. Try email or phone them tomorrow if you can wait.

 

[Coldspace]

Dan

Can't seem to find the higher rated gauge on the website? Do you have a link as I'm just about to send the oder off.

I'll buy something off ebay if they don't have it.

Thanks

You will need to get the kk low pressure gauge rated upto 80-100 psi. They are $9.95 last time I bought one.
Put into kk search bar, "pressure gauge" it should show up or call them.
Some thread seal tape and spanner and your away.

Cheers

 

[Dan Pratt]

Im now onto my 4th beer of pressure fermentation. Since the first beer at 23c and 15psi I have toned it back to the std temp of 18c and around 10-11psi.

I will get a much better read of the suppression of the esters when i do my Fake Blonde using W34/70 lager yeast @ 15c. I have done 2 previous batches without pressure in the old coopers FV and they both had estery aroma combined with the dry hop so I will get a real tell sign with that beer for the true effects of the pressure ferment.

Some feedback from this post above:

Ive done over a dozen pressure fermented beers now and have moved the PSi to 5-7. Reason is I made an IPA with 007 at 13psi and the the beer had an infected flavour and I put it to the pressure ( yeast stress ), so I've taken the once bitten twice shy with the higher pressure and since no issues with lower pressure, because its still pressure.

Anyway to report on the recent beer - fake blonde 3 with W34/70 @ 15c and 7psi....not an ester to be smelt!! Just clean aromatic hops from the dry hopping

 

[wobbly]

Horses for courses I guess but I (and others) ferment in our WW's starting with the VPRV (Spunding valve) set to control at 1.5bar (21psi) and wort temperature at 23C and allow the pressure to build up over the first 24hrs and under these conditions a 1040 Ale beer using US-05 or Nottingham will have fully fermented out in 4 days then crash chill and clarify. For lagers again pitch yeast at around 23C with spunding vale set to control at 1.5bar and set temperature controller to bring the wort down to 15C over the first few hours and hold at that temperature for the first 3 days and then raise temperature setting to 18C for another three days by which time a 1040 lager using W34/70 or S-04 will have fully fermented in the 6 days and then crash chill and clarify. For wort at higher OG's up to say 1055/60 you may need to add 1 day to the above times.

Just my 2c worth of input into this subject

Wobbly

 

[Maximus Humulus Lupulus]

I wouldn't be too worried about the pellet density, in fact the tighter the better for mine (reduces oxygen penetration). The only thing that holds pellets together is the naturally occurring rosins and waxes in the hops, hop cones are ground to powder and then put through an extruder. The higher the pressure and the higher the amount of natural binders the tighter the pellets.
Shure the vid above looks convincing, but come back in half an hour and I strongly suspect you would be hard presses to tell the difference. Just go for the best hops you can get, look after them and enjoy.
Mark

I wish that was the case, MHB, but the high density pellets (in this instance, Cascade) sank immediately to the bottom of FV 1 and remained there for the duration fo the dry hop (3-4 days). Even rousing them by bubbling CO2 up from the bottom of the FV didn't work. They just sank straight back to the bottom, where, in my opinion, their efficacy in terms of disseminating aroma and flavour compounds is compromised to the point of insignificance. Especially in a conical.

The lower density pellets added to FV 2 (in this instance, Mosaic) floated on the top and took over three days to sink to the bottom.

I've still got a kilo of the high density pellets left so will do my best to post a video next time I use them (though in truth I'd rather chuck the buggers. Or I might try whazzing them through a blender to break them up a bit.)

 

[Lyrebird_Cycles]

Question is I'm going to dry hop with around 4 gravity points left before terminal. If I didn't reconnect the gas disconnect blow off tube would the pressure build too much (>20psi)?

I'm fermenting an ale with Nottingham at 18c.

Thanks a bunch.

At 18 oC an extra 10.25 g/l sugar (equivalent to your stated gravity difference) will result in about 260 kPa pressure, which is about 38 PSI. That assumes you reached equilibrium when depressured for dry hopping, by no means assured.

 

[Lionman]

H2O + C12H22O11+ 3,4-Dihydroxy-5-(3-methylbut- 2-enyl)-2-(3-methyl-1-oxobutyl)-4-(4- methyl-1-oxopent-3-enyl)-1- cyclopent-2-enone+ Saccharomyces cerevisae in order to produce C2H5OH and various byproducts and waste material including polypeptides and saccharides.

I love chemicals in my beer.

Technically those chemicals ARE the beer, not added to it.

 

[Lionman]

Could I potentially swap the gauges between my keg keng reg and spunding valve? Are they the same thread?

The reg has a too high pressure gauge considering I only use it at about 12c which is a fraction of its travel and its hard to get it accurate at all.

 

[Digga]

It's been mentioned in another thread that they are the same I'll be doing the same with mine when it arrives. Hopefully before the weekend as I have a pressure fermenter that is being less than fully utilized.

 

[manticle]

Technically those chemicals ARE the beer, not added to it.

CO2 if kegging, C12H22O11 if bottling.

Apologies to purists for lack of subscript.

Phone and lazy finger.

 

[Crusty]

Some feedback from this post above:

Ive done over a dozen pressure fermented beers now and have moved the PSi to 5-7. Reason is I made an IPA with 007 at 13psi and the the beer had an infected flavour and I put it to the pressure ( yeast stress ), so I've taken the once bitten twice shy with the higher pressure and since no issues with lower pressure, because its still pressure.

Anyway to report on the recent beer - fake blonde 3 with W34/70 @ 15c and 7psi....not an ester to be smelt!! Just clean aromatic hops from the dry hopping

It's seems odd that you got an infected flavour from 13psi. The yeast should be under no additional stress at that psi setting causing off flavours but it's the result you got, thanks for letting us know. I fermented my Lager at 12psi with no off flavours whatsoever.
I'm drinking from the fermenter & I never use any finings like gelatine or biofine but next time I will clarify in the fermenter then transfer to a serving keg. I wouldn't recommend just cold crashing to clear your beer as I normally do if fermenting under pressure & naturally carbonating. My Lager has cleared pretty well but it won't be as clear as I normally get it due to the pressure ferment & lack of finings.