Pressurized fermentation.

[wobbly]

Have a lot at this thread where you will find a PDF file on the subject of pressure fermenting and the impact of various pressures as well as impact on Ester and Fusel production etc

http://onlinelibrary.wiley.com/doi/10.1002/j.2050-0416.1992.tb01137.x/abstract?globalMessage=0

Cheers

Wobbly

 

[Beerisyummy]

And this one!

http://onlinelibrary.wiley.com/doi/10.1002/j.2050-0416.2001.tb00083.x/pdf

 

[MastersBrewery]

Have we had any further development of experience/ knowledge in this area?

 

[Beerisyummy]

I made a lager that I've named "Two bob lager". So named because it was treated like a dirty, two bob thing.

Anyway, it fermented out at 25c with german lager yeast and is still quite drinkable. I've done similar with a glad wrap fermenter and have had much funkier results.
The results I've had so far are anecdotal at best. They still hint towards this being a useful addition to the brew shed.

PS. I'm currently testing my garden tap spunding valve. Once I have it working properly I'll share the parts list.
:beer:

 

[Mardoo]

Hey there Dave70, any word on how this is working out for you?

 

[gordo_t]

I gave this a whirl the other week for the first time in one of my standard corny kegs and spunding valve.
I did a lager using s-23, fermented @ 15 degree (slowly built up to 12psi, which was the maximum that my valve would allow, i.e. < 5 psi for first few days then increased). Drinking now at 4 weeks, its nothing too special but certainly drinkable, think there are a few fusal alc tastes there. I think on the next attempt i might do it a degree or two lower with slighly more pressure early on.

 

[hockadays]

I've tried this and you need to have a good valve for adjusting the pressure. Beware of filling a corny keg up too much and doing it as you can end up with beer in your valve and pressure gauge. Been there! The homebrewtalk talk thread has all the info required. Finding suitable components is the key, but it does work. I have only bunged lagers rather then pressure fermented them so can't comment on this.

 

[Dave70]

Hey there Dave70, any word on how this is working out for you?

If I'm honest, I'd kind of forgotten all about it, so I'm glad the thread got bumped. I've been more concerned with acquiring / building other do dads like stands, a chiller and a great big pot so I can do stuff like pain free step mashes. The old faithful esky has its limitations and is (literally) starting to crack under the strain.
Look, for a hand full of fittings, a few bucks and ten minutes of your time it's certainly worth having a go as the idea certainly seems to have merit.

 

[Beerisyummy]

I gave this a whirl the other week for the first time in one of my standard corny kegs and spunding valve.
I did a lager using s-23, fermented @ 15 degree (slowly built up to 12psi, which was the maximum that my valve would allow, i.e. < 5 psi for first few days then increased). Drinking now at 4 weeks, its nothing too special but certainly drinkable, think there are a few fusal alc tastes there. I think on the next attempt i might do it a degree or two lower with slighly more pressure early on.

Way more fun in a big keg!

I'm still going on this experiment and will keep posting my results.

The current batch is 5kg prem pils, 0.2kg acid and saaz to suit. This batch will be treated like a princess @ 15psi.

Even if the beer is not any better, the system still offers plenty of benefits for my brewery. It's quicker and cheaper to run for starters.
The downside is that the initial outlay is bigger and the FV is hard to move around.
(Both of these views are based on doing batches for 2x18l kegs).

Happy brewing.

 

[wobbly]

Those trying out pressure fermenting might be interested in the "Cornical" about to be marketed by Blichmann. See details in the attached web

Cheers

Wobbly

http://blichmannengineering.com/news/new-product-update

 

[Beerisyummy]

Those trying out pressure fermenting might be interested in the "Cornical" about to be marketed by Blichmann. See details in the attached web

Cheers

Wobbly

http://blichmannengineering.com/news/new-product-update

Saturday night beer porn!

 

[gordo_t]

My adjustable releif valve (same as pictured in the original post) seems to be continually leaking, i.e. i can't hold pressure stable, if I charge to say 5 psi, it slowly leaks to 0 in about an hour).

I checked by dunking in some soapy water and can see it slowly but surely bubbling out the end valve. Tried some keg lube around the seal to see if it slows it at all but no luck.

Are they not designed to hold steady pressure at all, or do i have a dud here?

 

[DJ_L3ThAL]

My adjustable releif valve (same as pictured in the original post) seems to be continually leaking, i.e. i can't hold pressure stable, if I charge to say 5 psi, it slowly leaks to 0 in about an hour).

I checked by dunking in some soapy water and can see it slowly but surely bubbling out the end valve. Tried some keg lube around the seal to see if it slows it at all but no luck.

Are they not designed to hold steady pressure at all, or do i have a dud here?

An adjustable relief valve, functioning correctly should only vent out at the desired pressure. So it sounds like you have a faulty unit.

 

[gordo_t]

An adjustable relief valve, functioning correctly should only vent out at the desired pressure. So it sounds like you have a faulty unit.

I managed to get it working at bit better by stretching the spring in the valve ever so slightly. still very touchy though, might have to source a new one.

 

[wobbly]

Not sure if this is allowed but anyway

This post on another forum has something like 194 pages of details and info/benefits/process etc on setting up and using 50lt kegs to pressure ferment in which might be of interest to those wanting to go down that road

http://www.homebrewtalk.com/f13/closed-system-pressurized-fermentation-technique-44344/

Cheers

Wobbly

 

[MastersBrewery]

The yanks are using 15.5 gal kegs so about 58L so a 50l keg posses the problem of reduce head space, in a conical they say to leave or account for 20% head space, so for a double batch its cutting a little close though I guess there's only one way to find out. Of note iBrew just south of brissy I think had some US sanke kegs for sale might be worth checking out. My favourite conical if I could afford to import it would be these, price is awesome but don't know what it would be worth to ship (note they come in under the $1000 so no gst) I know guys have brought in big bilchmans with shipping forwarding companies might be worth checking out.

Oh and the conicals I linked to are leak tested at 100psi so well and truely good to go

 

[rehabs_for_quitters]

I am looking at doing 50L kegs into pressurised conicals, I haven't done the math to well but once you add the cone you will increase the volume by around 10 to 15 litres at least so should be with in cooey for head space I would think, and they wold handle the pressure happily

 

[dent]

I've been fermenting under pressure the last few years. I've tried a few different relief valves, currently I have settled on these:

Pressure cooker jigger valve

They're very cheap, and have a low hysteresis which I prefer. The thread is close enough to 1/8" BSP you can get it in with a decent amount of thread tape. There is no pressure adjustment - it is only fortunate that the pressure these start to let go is about perfect for fermentation. Most of these and other small PRVs like it leak a tiny amount over time - I find it quite beneficial to put a small valve in series with the PRV so you can use higher pressures for oxygenation and transfers if required, as well as simply sealing it off when fermentation is complete. Obviously never leave it closed at the start of the ferment!

I have also experimented with replacing the spring in the built-in PRV in a corny keg, which works OK - corny kegs are a bit of a pain to sanitise as effectively as a 50L keg - those you can just bung on the gas burner with a bit of water inside, and boil away. You can even put the pressure cooker valve to its intended use if you're feeling brave.

 

[Online Brewing Supplies]

I've been fermenting under pressure the last few years. I've tried a few different relief valves, currently I have settled on these:

Pressure cooker jigger valve

They're very cheap, and have a low hysteresis which I prefer. The thread is close enough to 1/8" BSP you can get it in with a decent amount of thread tape. There is no pressure adjustment - it is only fortunate that the pressure these start to let go is about perfect for fermentation. Most of these and other small PRVs like it leak a tiny amount over time - I find it quite beneficial to put a small valve in series with the PRV so you can use higher pressures for oxygenation and transfers if required, as well as simply sealing it off when fermentation is complete. Obviously never leave it closed at the start of the ferment!

I have also experimented with replacing the spring in the built-in PRV in a corny keg, which works OK - corny kegs are a bit of a pain to sanitise as effectively as a 50L keg - those you can just bung on the gas burner with a bit of water inside, and boil away. You can even put the pressure cooker valve to its intended use if you're feeling brave.

Mods please remove to Ghetto thread :lol:
Nev

 

[mr_wibble]

I made a lager that I've named "Two bob lager". So named because it was treated like a dirty, two bob thing.
Anyway, it fermented out at 25c with german lager yeast and is still quite drinkable. I've done similar with a glad wrap fermenter and have had much funkier results.

So are you saying you had *less* esters in the final beer?

I read something about open fermentation (for wheat beer) the other day.
The author suggested open fermentation produced more esters, and thus it seems to line up.