pressure fermenting an ale

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aussie brewer

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Hi, i just bought myself a fermzilla with the pressure kit. Im brewing a pale ale tomorrow with wlp001 and not sure how to pressure ferment. Anyone have any advice on how to do this? cheers brewers!
 
Hi, i just bought myself a fermzilla with the pressure kit. Im brewing a pale ale tomorrow with wlp001 and not sure how to pressure ferment. Anyone have any advice on how to do this? cheers brewers!
One advice, I learnt the hard way. Before you set fermzilla to ferment, connect a co2 line and pressurise the fermzilla a bit to check for leaks & to ensure the lid has firmly set. Even after you pour in wort, do pressurise to ensure proper seal.
I lost all aroma of hops along with the pressure and had to use co2 to re-carbonate. Also the poppet was leaking, tried good old paste but I ultimately managed to fix using plumbers tape. I made a small batch only initially. In the end, managed to troubleshoot and make a lovely chocolate stout.
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Yes. Don't.

Pressure fermenting an ale makes no sense and will simply ruin your beer.
thanks for the tip, i just brewed and put an airlock on. Im thinking of adding about 5psi after i dry hop it in 4 days?
 
One advice, I learnt the hard way. Before you set fermzilla to ferment, connect a co2 line and pressurise the fermzilla a bit to check for leaks & to ensure the lid has firmly set. Even after you pour in wort, do pressurise to ensure proper seal.
I lost all aroma of hops along with the pressure and had to use co2 to re-carbonate. Also the poppet was leaking, tried good old paste but I ultimately managed to fix using plumbers tape. I made a small batch only initially. In the end, managed to troubleshoot and make a lovely chocolate stout.
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Thanks for the advice! i sterilized it ready for filling and did a quick pressure test and the collection thing on the bottom was leaking.I unscrewed it and didnt tighten it as much, now no leaks!
 
Pressure after fermentation is done is not an issue, it's during primary that it will have major effects on beer that are detrimental to an ale fermentation, making it come out bland and characterless.
Doing a lager at higher temps is what the process was designed for and if done properly it works quite well too.
 
Pressure after fermentation is done is not an issue, it's during primary that it will have major effects on beer that are detrimental to an ale fermentation, making it come out bland and characterless.
Doing a lager at higher temps is what the process was designed for and if done properly it works quite well too.
^^^THIS.
 
You can pressure ferment an ale without ruining it. You just have to understand what pressure is doing and why you might want pressure and how much.
Pressure may reduce esters. It also lets you ferment at higher temps without the fusel alcohol flavors associated with high fermentation temps.
If you are dry hopping pressure can help hold aromas that would otherwise be blown off.
So yes you can ferment ales under pressure with fantastic results.
 
Let's see, pressure fermenting will:

- slow down fermentation, all else being equal
- reduce ester and fusels which are an essential part of ale character
- not affect dry hopping a iota (except to make it very difficult to do post-fermentation as you'll be dealing with a pressurized vessel) as even with pressure fermentation you will still be releasing over 90% of fermentation CO2 or the fermenter will blow up on day one. Since there is no way to separate CO2 from any other volatile component you'll be releasing just as much hop aroma as you would with an open fermentation
- if you want fermentation to proceed at least as fast with pressure as it would without you'll need to either increase temperature or increase pitch rate or both, all of which will reduce ester and fusel formation even further

I'm sorry but I still don't see any advantage in fermenting an ale under pressure. If I wanted to get a beer that tastes like a lager I'd ferment with a lager yeast, possibly under pressure if the time saved were indeed of advantage to me (it isn't BTW). Of course I don't factor the "fad" or "novelty" factor in my assessment as I personally find it irrelevant.
 
Let's see, pressure fermenting will:

- slow down fermentation, all else being equal
- reduce ester and fusels which are an essential part of ale character
- not affect dry hopping a iota (except to make it very difficult to do post-fermentation as you'll be dealing with a pressurized vessel) as even with pressure fermentation you will still be releasing over 90% of fermentation CO2 or the fermenter will blow up on day one. Since there is no way to separate CO2 from any other volatile component you'll be releasing just as much hop aroma as you would with an open fermentation
- if you want fermentation to proceed at least as fast with pressure as it would without you'll need to either increase temperature or increase pitch rate or both, all of which will reduce ester and fusel formation even further

I'm sorry but I still don't see any advantage in fermenting an ale under pressure. If I wanted to get a beer that tastes like a lager I'd ferment with a lager yeast, possibly under pressure if the time saved were indeed of advantage to me (it isn't BTW). Of course I don't factor the "fad" or "novelty" factor in my assessment as I personally find it irrelevant.

I have not seen any showdown in fermentation, Some day it’s actually a bit faster ferment. You’d think the year would slow under pressure. I’m kegging on the same schedule I would in a car it.

You can still get plenty of esters. Unless you go crazy with pressure you are not putting the beer under any more stress than the bottom of a large commercial fermenter.

It’s not for everyone. As with most things homebrew there are many ways to brew, and that’s what makes this hobby so much fun.
 
Unless you go crazy with pressure you are not putting the beer under any more stress than the bottom of a large commercial fermenter.

This is an enormous misconception among homebrewers, and in fact part of the origin of the fad for pressure fermentation among them. "We should ferment under top pressure to mimic the conditions in a commercial fermentation."

Head pressure and hydrostatic pressure are two entirely different animals, and their effects on yeast and fermentation are entirely different.

Hydrostatic pressure is always deleterious to yeast, and head pressure can be, as both increase osmotic pressure and concentration of CO2.

Homebrewers are at a great advantage over commercial brewers in that hydrostatic pressure is not an issue for us.

Care should be taken in manipulating head pressure, making sure you understand its effects both harmful and useful.
 
It’s not for everyone. As with most things homebrew there are many ways to brew, and that’s what makes this hobby so much fun.
Just out of curiosity, what advantages do you think pressure fermentation has when making an ale? Let's set aside natural carbonation as you can get that just with spunding at the end of fermentation, you clearly don't need to conduct the whole fermentation under pressure just for that.
 
Hydrostatic pressure is always deleterious to yeast, and head pressure can be, as both increase osmotic pressure and concentration of CO2.

Hydrostatic pressure has no effect on concentration of dissolved CO2, it's only a function of pressure at the gas/liquid interface.
 
Just out of curiosity, what advantages do you think pressure fermentation has when making an ale? Let's set aside natural carbonation as you can get that just with spunding at the end of fermentation, you clearly don't need to conduct the whole fermentation under pressure just for that.
You can ferment regular ale yeast at slightly elevated temperatures. I have fermented ales at 80F without a trace of fusel. This results in a quicker turnaround. You can also tap down esters (if you want to do that) so hop character is the shining star.
Brewing a British ale would not be useful with at pressure as the esters are forefront and important in that style. That said I have done Belgians under a little pressure and the phenols are unaffected.
It’s just another tool in the brewers arsenal.
 
a bit off topic, am i supposed to dump the trub from the collection vessel?
Is the trub made up of yeast, break material and hops? I only save the trub if I only transferred clear wort (no protein or hops).

How are you liking that Fermzilla? I'm thinking about getting one. Which model are you using?
 
You can pressure ferment an ale without ruining it. You just have to understand what pressure is doing and why you might want pressure and how much.
Pressure may reduce esters. It also lets you ferment at higher temps without the fusel alcohol flavors associated with high fermentation temps.
If you are dry hopping pressure can help hold aromas that would otherwise be blown off.
So yes you can ferment ales under pressure with fantastic results.

Im pressure fermenting an ale at 80°, how many days should i let it ferment before i cold crash it?
 
You need to check gravity before cold crashing. What pressure you fermenting at? You will see when fermentation is finished.
Do you have a spunding valve?
 
You need to check gravity before cold crashing. What pressure you fermenting at? You will see when fermentation is finished.
Do you have a spunding valve?
I will check it, 1 bar, i have a spunding valve & i cannot see it cause im fermenting in a corny keg, today is my 4th day and the pressure is not as high as the last 2 days..
 
Your pressure should maintain. If it's less then you have a leak.
As for time I just brewed a Hefe at 6 psi. Brewed last Friday and it's done. fermentation started Saturday so 6 days. Going to keg tomorrow.
 
Even if you end up not wanting to ferment under significant pressure for an ale, you can still do good things with the pressure fermenter:

1) Use the fermentation gas to purge some kegs
2) Complete close system transfer at the end
3) You can spund and let the pressure rise at the end to get a head start on carbonating.
4) Cold crash is super easy with zero oxygen exposure

That said, since my fermentasaurus is much more of a pain to clean, for ales that don't REALLY need a cold crash or are likely to be super oxygen sensitive, I don't use it. But I'm glad I have it. I'm going to be doing my first lager (under pressure start to finish) in it soon.

Also ymmv but I would not dump trub during fermentation. You are just going to let a bunch of oxygen in for likely no benefit.
 
Even if you end up not wanting to ferment under significant pressure for an ale, you can still do good things with the pressure fermenter:

1) Use the fermentation gas to purge some kegs
2) Complete close system transfer at the end
3) You can spund and let the pressure rise at the end to get a head start on carbonating.
4) Cold crash is super easy with zero oxygen exposure

That said, since my fermentasaurus is much more of a pain to clean, for ales that don't REALLY need a cold crash or are likely to be super oxygen sensitive, I don't use it. But I'm glad I have it. I'm going to be doing my first lager (under pressure start to finish) in it soon.

Also ymmv but I would not dump trub during fermentation. You are just going to let a bunch of oxygen in for likely no benefit.

^this
 
Yes. Don't.

Pressure fermenting an ale makes no sense and will simply ruin your beer.
This response is so lazy….. don’t post a short response with no supportable info to trash someone. So you fermented under pressure and had a bad experience? Or are you regurgitating other information you’ve seen other people regurgitate? Please share
 
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This response is so lazy….. don’t post a short response with no supportable info to trash someone. So you fermented under pressure and had a bad experience? Or are you regurgitating other information you’ve seen other people regurgitate? Please share
I saw that post and thought, man you are so wrong. Thoughts on this have changed a bit since 2019. I ferment under pressure and it's awesome. I wouldn't do it for hefes/Belgians, and maybe some British styles, but I did an Irish Red earlier this year and it was fantastic. Pressure fermenting has literally almost every advantage, for ales, particularly hoppy styles, it locks in the hop flavor/aroma so much more.
 

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