Can you pressure ferment ales to replicate a colder fermentation without eliminating all the esters?

[whatstyleguidelines]

I recently acquired a used fermzilla, so I'm reading up on pressure fermentation. I know it's pretty standard to ferment a lager or even an ale at 10-15 PSI to create a very clean beer (few to no esters and fusels). However, I was wondering if it's possible to pressure ferment at room temp (70ish here rn) an get the right profile from an ale yeast that would ordinarily be fermented at 60-65° F. Essentially, can I apply 1-10 PSI and eliminate fusels and the excess esters you would get from fermenting a British ale, kolsch, etc. too warm, while still keeping the characteristic ester profile?

TLDR, if fermenting with high pressure replicates a 50°s lager-cold fermentation, does fermenting with less pressure replicate a controlled 60s ale fermentation.

 

[Franktalk]

Frankly, I'm not sure why you want to. You shouldn't end up with fusels with the temperatures you mention. Pressure fermentation definitely suppresses ester production, so if you want the esters let it rip. Most ale yeasts won't get too fruity at 65-70 F. If you want to use your new toy, brew a lager.

 

[Dgallo]

The only option I think you could employ would be cooling your beer to 65*f before pitching. most esters are formed during yeast’s growth phase, primarily in the first 48hr after pitching. So you might have a change letting the beer ferment until the beer free rises to 70-72*f and then put your spunding valve on. This could potentially work for you and allow the esters and prevent fusel.

That said, There’s plenty of ale yeast that would be ok in the 70-74 *f range If you can maintain that, than you would be ok

 

[Bassman2003]

I would say experiment with pressure fermentation. It is very interesting and changes the beer a little. To your question, I would say it is style dependent imho. There is little need to pressure ferment an English style because that is not a flavor profile associated with that beer/yeast. The fermentation temps are not difficult and the yeast are up to the task. Since you are looking to retain esters, then I would say you might be threading the needle a bit. But try it, the beer will still be very good. I brewed a Scottish Ale at 30PSI in the high 60's F. It tasted very nice and had great mouthfeel. But I it was "cleaner" than when I make it at atmosphere. Basically, it tasted more "macro" than "craft".

One thing I will add, pressure tends to bring out the hops as you increase the amount. The lack of fusels seems to make room for hop character to shine through. So your scenario works great for IPAs. I always do my IPAs at 30PSI 70 F now. It is sort of like a music compressor if you know about that. It scruntches and amplifies!

 

[Dgallo]

I. I always do my IPAs at 30PSI 70 F now. It is sort of like a music compressor if you know about that. It scruntches and amplifies!

The reason your hops are what you are calling amplified is because there is no ester character competing with them. Pressure fermenting itself does not elevate hop character. I would suspect you could achieve the same outcome just using US05 and no pressure. That exactly how I brew my modern west coast IPAs and they are clean and vibrant. Sometimes I even use 34/70 as lager yeast do hold the potential to elevate hop character

 

[Bassman2003]

I think you are mis-interpreting my post. I mentioned the lack of fusels making room for the hops to shine, esters as well too. Pressure per se does not do anything that I know of to the hops. But for sure, the application of pressure does amplify the hops as an end result. Just using US05 would not achieve the same outcome because the 30PSI IPA ferments are with a Chico strain!

 

[Dgallo]

I think you are mis-interpreting my post. I mentioned the lack of fusels making room for the hops to shine, esters as well too. Pressure per se does not do anything that I know of to the hops. But for sure, the application of pressure does amplify the hops as an end result. Just using US05 would not achieve the same outcome because the 30PSI IPA ferments are with a Chico strain!

Def can argue with someone’s experience on their system. I’ve done side by sides (same beer split) of pressure ferments vs non and only one person of 8 could correctly identify the different beer in a triangle tasting. I personally could not. Lots of ways to skin a cat though for sure and still produce great beers!

 

[Bassman2003]

I don't think the difference shows up very much until you go over 1 bar and higher. It is pretty nuanced for some styles. But for hops, it is a real thing when you go up to 2 bar. When I do cold larger fermentation at 2 bar I lower my IBUs in the recipe by about 10 units. That is why I always mention experimenting with pressure fermentation, it does some cool stuff if you push it. I know homebrewers that ferment at 3 bar and love the unique flavor. But it turns into an Olympic event for the yeast.

 

[beersk]

I think the pressure fermentation keeps the aroma from the hops in the fermenter rather than blowing it off, works fantastically with preserving dry hop aroma in my experience.