Pressurized Fermentation - Worth It?

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Jeremy W

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I've been fermenting in various carboys and buckets for a few years and most recently have had good success with a 7 gal Fermonster that I've added a thermowell, ball lock gas post and spigot which allows me to do closed gravity transfers to my kegs. It works great but I've got my eyes on the future and potentially moving to some kind of conical.

Wanted to understand what the true benefits of fermenting under pressure are in a homebrew setting. I get that being able to spund/carbonate right in the fermenter, like what could be done in a Spike CF or SS Brewtech Unitank could cut down on turnaround time, but is it worth the extra $$ to go to a vessel with a pressure rating higher than 1 psig? I've heard that the additional pressure can lead to ester suppression, especially in lagers.

I guess what I'm really asking is: does anyone who purchased a Chronical (or other conical with only a 1 psig pressure rating) regret not going to a Spike CF or an SS Unitank, or other?

I fully get that moving to most conicals means going glycol and all that (unless you have an upright freezer or something), but I'm most curious about the pressure rating aspect itself.

Thanks!
 
I would review your goals. Why do you want to pressure ferment? Why do you want to spund? Those are different things, even though they may use similar equipment.

Pressurized fermentation requires a special fermenter. Spunding happens either in the fermenter OR in the serving keg, so it may not require a special fermenter. If you only really care about the natural carbonation and slightly shorter schedule that spunding permits, you don't need a pressurized fermenter at all.

It is worth noting that kegs make great pressure-capable fermenters, killing two birds with one stone.

If you are unable to maintain certain temperatures, particularly as is suitable for lager yeast (46-52F), you may want to ferment lager entirely under pressure at more convenient, warmer temps. Usually, ales are not recommended for pressure ferm because yeast expression, which is desired, will be surpressed.

And then, as you have noted, you have to consider the less convenient aspect of larger conical fermenters in terms of where to put them and how to move them.
 
I have fermented a handful of brews under pressure and I find that it does help with lagers if you want to 'fast lager', but I didn't care for the results from the ale fermentations. I found that it would mute the malt flavor and I don't even know how to describe the hop flavor. It was consistent on 2 different recipes (pale and an IPA) with the same end result.
(I do cap and spund almost every beer these days when nearing TG, I'm referring to pressurizing from the start)
 
I would review your goals. Why do you want to pressure ferment? Why do you want to spund? Those are different things, even though they may use similar equipment.

Pressurized fermentation requires a special fermenter. Spunding happens either in the fermenter OR in the serving keg, so it may not require a special fermenter. If you only really care about the natural carbonation and slightly shorter schedule that spunding permits, you don't need a pressurized fermenter at all.

It is worth noting that kegs make great pressure-capable fermenters, killing two birds with one stone.

If you are unable to maintain certain temperatures, particularly as is suitable for lager yeast (46-52F), you may want to ferment lager entirely under pressure at more convenient, warmer temps. Usually, ales are not recommended for pressure ferm because yeast expression, which is desired, will be surpressed.

And then, as you have noted, you have to consider the less convenient aspect of larger conical fermenters in terms of where to put them and how to move them.

yeah, I certainly need to put some more thought into it, before making any decisions one way or the other. There's also an element of "it it ain't broke, don't fix it" with my current process but I like the idea of dumping yeast/trub though.

I have fermented a handful of brews under pressure and I find that it does help with lagers if you want to 'fast lager', but I didn't care for the results from the ale fermentations. I found that it would mute the malt flavor and I don't even know how to describe the hop flavor. It was consistent on 2 different recipes (pale and an IPA) with the same end result.
(I do cap and spund almost every beer these days when nearing TG, I'm referring to pressurizing from the start)

Good to know!
 
Regarding dumping yeast and trub... as the owner of a plastic conical, the Catalyst, it's just one way of doing things and not necessarily superior. I would probably use the Catalyst more but it doesn't fit into any of my temperature-controlled spaces.

It's easy enough to keep trub out of the fermenter in the first place, obviating the need to dump it later. And I find it equally easy to collect yeast from the fermenter after I've racked the beer - just pour it out through the top! When there's little or no trub, it's all good yeast and you don't even have to wash it.

Really not trying to discourage, just raising some of the practical points that I have considered myself.
 
I went from buckets to carboys to Speidel fermenters to Better Bottles to....well, you get the idea. After a series of probable infections I decided to try stainless steel. Got a Brew Bucket. Immediately I saw the benefit of stainless, but also the limitations, or more correctly the possibilities of a stainless conical.

So I got a Chronical. Loved it. But soon saw the limitations of a basic conical fermenter based on what I wanted to be able to do. So I got a Unitank. Once again, love at first brew, only this time the love affair endures.

You know what the abilities and limitations of each piece of gear are, so I won't repeat them. But what you have to decide is what you want/need to do and whether it's worth the extra expense. I really like having the ability to do pressure transfers without constantly worrying about pressure spikes above 2.5 psig blowing the lid or ruining my fermenter. I spund every brew batch and never am concerned with suck back from the blow-off line when I cold crash. Of course it's great to dump trub and harvest yeast, and yes you can do that with a standard conical. It's just easier to do when you don't need to keep a low pressure differential maximum.

The one thing I haven't seen a benefit in yet has been fermentation under pressure. I've tried it a few times and really don't see the benefit, especially in the homebrew situation. It may allow you to brew lagers at a higher temperature and thus shave a few days off the time to brew a lager. Could help a micro brewery crank out beer faster, but the gains for me were minimal at best. Not the reason I bought it anyway.

But to answer your original question, if I had to choose just one item and money wasn't a factor, I'd go with the Unitank because of it's flexibility. That said, I still use the Brew Bucket and Chronical though not as much as the Unitank. Different tools for different purposes, but just like the torque wrench in my tool box that I haven't used in years, I'm glad I still have it.

Brooo Brother
 
I went from buckets to carboys to Speidel fermenters to Better Bottles to....well, you get the idea. After a series of probable infections I decided to try stainless steel. Got a Brew Bucket. Immediately I saw the benefit of stainless, but also the limitations, or more correctly the possibilities of a stainless conical.

So I got a Chronical. Loved it. But soon saw the limitations of a basic conical fermenter based on what I wanted to be able to do. So I got a Unitank. Once again, love at first brew, only this time the love affair endures.

You know what the abilities and limitations of each piece of gear are, so I won't repeat them. But what you have to decide is what you want/need to do and whether it's worth the extra expense. I really like having the ability to do pressure transfers without constantly worrying about pressure spikes above 2.5 psig blowing the lid or ruining my fermenter. I spund every brew batch and never am concerned with suck back from the blow-off line when I cold crash. Of course it's great to dump trub and harvest yeast, and yes you can do that with a standard conical. It's just easier to do when you don't need to keep a low pressure differential maximum.

The one thing I haven't seen a benefit in yet has been fermentation under pressure. I've tried it a few times and really don't see the benefit, especially in the homebrew situation. It may allow you to brew lagers at a higher temperature and thus shave a few days off the time to brew a lager. Could help a micro brewery crank out beer faster, but the gains for me were minimal at best. Not the reason I bought it anyway.

But to answer your original question, if I had to choose just one item and money wasn't a factor, I'd go with the Unitank because of it's flexibility. That said, I still use the Brew Bucket and Chronical though not as much as the Unitank. Different tools for different purposes, but just like the torque wrench in my tool box that I haven't used in years, I'm glad I still have it.

Brooo Brother

Thanks for all the great info, I have some pondering to do.
 
Other than dumping trub, a keg offers all of the pressure benefits of the steel conicals, and is much cheaper and easier to store around the average home-brewhouse. It's not as sexy though.

I agree with @Brooothru that pressurized fermentation doesn't do much for me, and I've tried it several times now. I have temp control, so it is easy to let things go without pressure until it's time to close 'er up and contain CO2 at the end for carbonation. Now that, I truly appreciate being able to do.
 
Other than dumping trub, a keg offers all of the pressure benefits of the steel conicals, and is much cheaper and easier to store around the average home-brewhouse. It's not as sexy though.

I agree with @Brooothru that pressurized fermentation doesn't do much for me, and I've tried it several times now. I have temp control, so it is easy to let things go without pressure until it's time to close 'er up and contain CO2 at the end for carbonation. Now that, I truly appreciate being able to do.

I think the thing that is really attractive for me is the ability to build up a bit of headspace in the fermenter prior to cold crashing. I'm currently using a mylar balloon to do that which works well, but if I'm making the investment in a new fermenter at some point, the ability to hold a bit of pressure seems like a really nice feature. How much pressure do you typically build at the end prior to cold crashing?
 
I'm doing my first pressure ferment and I hope it's worth it, but I've already ran into a hiccup. My floating dip tube is not working out as I can't get a sample to check gravity. Really sucks because I was hoping to have this brew totally closed through serving, but looks like I'm opening things up (unless someone has a bright idea for me).
 
I'm doing my first pressure ferment and I hope it's worth it, but I've already ran into a hiccup. My floating dip tube is not working out as I can't get a sample to check gravity. Really sucks because I was hoping to have this brew totally closed through serving, but looks like I'm opening things up (unless someone has a bright idea for me).
What kind of fermentor?

Have you tried giving a gentle swirl to see if you can it to right itself?
 
Corny keg. That I have not, but I suppose I can try.
On a side note, can anyone comment on the time fermenting a lager might take? Should I assume it will be similar to an ale being I am at ale temps? Thanks.
 
I'm A novice to pressurized fermentations but so far I love it. Did my first in a 5G corny with about 4.5 G. I now have a 10G Torpedo keg for the job. I've noticed much more hop presence when fermenting ales under pressure. This weekend, I'll be trying my first lager. I've never done lagers in the many years I've brewed because I lacked A controlled temp fermenter. We shall see Btw, the SPUNDit is a fabulous spunding valve, very precise dialing in on the pressure. So nice not having to waste co2 to carb a keg
 
Wanted to understand what the true benefits of fermenting under pressure are in a homebrew setting. I get that being able to spund/carbonate right in the fermenter, like what could be done in a Spike CF or SS Brewtech Unitank could cut down on turnaround time, but is it worth the extra $$ to go to a vessel with a pressure rating higher than 1 psig? I've heard that the additional pressure can lead to ester suppression, especially in lagers.

Since last August I've fermented major amount of my beers under pressure in kegs. Started with WLP925 and then moved to ales. Quick turnaround is a bonus but I'm more interested playing with higher fermentation temperatures, stressing the yeast (shout out to Dgallo for explaining how to stress Imperial A24 yeast) and trying to preserve more hop compounds. I agree what Gusso said about hop presence. Or at least I have noticed the same impact in my brews. You are right about suppressed esters. Fermenting under pressure reduces ester production especially the unwanted ester production.

I won't say that fermenting under pressure is the way to go but at least for me I haven't seen any negative impact what fermenting under pressure have done to my brews. Each to their own. I would still recommend for you to try this technique. If you don't like the results you can always go back with your previous method. It's just another tool to play with :)
 
I think the thing that is really attractive for me is the ability to build up a bit of headspace in the fermenter prior to cold crashing. I'm currently using a mylar balloon to do that which works well, but if I'm making the investment in a new fermenter at some point, the ability to hold a bit of pressure seems like a really nice feature. How much pressure do you typically build at the end prior to cold crashing?
It depends on the beer style, preferred CO2 level, and temp right before crashing.
https://www.brewersfriend.com/keg-carbonation-calculator/
For example, if I have an American Ale a few points away from terminal gravity at 65° and I want 2.2 volumes of CO2 (2.2-2.7 for that style) then I start spunding at 22psi. You'll just have to take extra care when transferring to a keg so you don't have a foamy mess. 🍻
PXL_20210804_192833488~2.jpg
 
It depends on the beer style, preferred CO2 level, and temp right before crashing.
https://www.brewersfriend.com/keg-carbonation-calculator/
For example, if I have an American Ale a few points away from terminal gravity at 65° and I want 2.2 volumes of CO2 (2.2-2.7 for that style) then I start spunding at 22psi. You'll just have to take extra care when transferring to a keg so you don't have a foamy mess. 🍻
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Hey Matt,

Totally off topic. Just wanted to comment on your avatar (Boxer). Our son (also Matt) got us started on the breed 20 some years ago when we were left to babysit his Boxer while he chased a job in Vegas. He eventually returned, but we wouldn't return the dog! Bacchus lived to be 15+. Since then he's had two. My daughter in Florida is on her third, and works with a Boxer rescue. Our next door neighbor is on his second. It would be an understatement to say we are enthralled by the breed.

Mods: much apologies for the hijacked thread, but I love Boxers. Best breed ever!
 
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