Pressure vs esters

[Djangotet]

Hey! I’m pretty new to brewing and I have been doing a ton of research into pressure fermentation. I am currently using my one and only fridge with a temp controller. With the fridge set to 60 my freezer is just cold enough to use as a fridge but I can’t really do a diacetyl rest without the freezer getting too warm.

Obviously, pressure fermentation at room temp is an attractive idea for me. I have seen some posts saying that pressure fermented NEIPA is one of the best they’ve made but I’ve seen tons of info saying it removes esters.

What is the actual range of viable styles for pressure fermentation? If I dial down the pressure to like 5psi, will that leave some esters behind? I live in Southern California so it’s always around 70 - 80 degrees.

I want to make great beers so if lagers are my only real option then I’ll stick with that. I can also use a lager temp in my fridge if that will make a better beer. I’m really just not sure if this is the right move?

I’ve also considered using San Francisco Lager yeast as a house strain but I think I would also be limiting myself there. I worry that many styles would fall flat if I only use that lager yeast.

 

[Red over White]

It has been my experience that you really have to take every yeast case by case. For example S23 will be very clean at low pressure 2-5 psi in the low 60's. Verdant is tough to just stifle until I get to 15 psi, with 10% invert in the recipe it takes 20+ psi for me.

I recommend starting lagers in the low 60's and ales in the mid 60's and let the temperature rise slowly as the pressure natively builds, this allows growth in the fermenter. Headspace will determine how fast pressure will build.

California lager will be very clean at even low pressure, but maybe not a good choice for a NEIPA. You will likely need a house lager and a house ale yeast for pressure fermentation IME.

The studies I have read about pressure fermentation while insightful, don't always translate into what is in my pint glass. Yeast strain, pitch rate, temperature, when pressure is applied, variable pressure schemes and wort composition all have an impact. If you like the yeast in a traditional ferment, you will likely love it under pressure. Pressure fermented beers are cleaner in many ways from the start and exhibit rapid maturation because of that. Have fun with it!

 

[Djangotet]

It has been my experience that you really have to take every yeast case by case. For example S23 will be very clean at low pressure 2-5 psi in the low 60's. Verdant is tough to just stifle until I get to 15 psi, with 10% invert in the recipe it takes 20+ psi for me.

I recommend starting lagers in the low 60's and ales in the mid 60's and let the temperature rise slowly as the pressure natively builds, this allows growth in the fermenter. Headspace will determine how fast pressure will build.

California lager will be very clean at even low pressure, but maybe not a good choice for a NEIPA. You will likely need a house lager and a house ale yeast for pressure fermentation IME.

The studies I have read about pressure fermentation while insightful, don't always translate into what is in my pint glass. Yeast strain, pitch rate, temperature, when pressure is applied, variable pressure schemes and wort composition all have an impact. If you like the yeast in a traditional ferment, you will likely love it under pressure. Pressure fermented beers are cleaner in many ways from the start and exhibit rapid maturation because of that. Have fun with it!

I am now also thinking of using Essex yeast because it has fruity esters and I’ve heard that they come through. I also heard that verdant IPA esters come through under pressure like you mentioned. Are you saying that verdant IPA esters would come through below 10psi? I actually have a package of that coming in the mail..

 

[Red over White]

I am now also thinking of using Essex yeast because it has fruity esters and I’ve heard that they come through. I also heard that verdant IPA esters come through under pressure like you mentioned. Are you saying that verdant IPA esters would come through below 10psi? I actually have a package of that coming in the mail..

Yes, namely the Apricot ester survives pressure fermentation for me. The more simple sugars present in the wort, accentuates Verdants Apricot ester even under pressure. Simple sugars are known to be ester fuel for some beer styles with a specific yeast (banana and clove esters in wheat beer for example). It appears to be the case with Verdant as well for me, but I do mash for attenuation and even more so when adding invert sugar.

 

[Djangotet]

Yes, namely the Apricot ester survives pressure fermentation for me. The more simple sugars present in the wort, accentuates Verdants Apricot ester even under pressure. Simple sugars are known to be ester fuel for some beer styles with a specific yeast (banana and clove esters in wheat beer for example). It appears to be the case with Verdant as well for me, but I do mash for attenuation and even more so when adding invert sugar.

I heard about that actually. There was an article online about corn sugar being a close enough substitute for the usual mash steps to getting more banana flavor. The taste testers all knew which had the banana esters so I may give that a shot. Thank you for your help!

 

[VikeMan]

Simple sugars are known to be ester fuel for some beer styles with a specific yeast (banana and clove esters in wheat beer for example).

Just a small nit to pick. The clove in a hefewizen (4-vinyl guaiacol) is a phenol (not an ester), and doesn't (to my knowledge) depend on any particular sugar profile. But it is a function of available ferulic acid, which can be increased by doing an acid rest.

 

[Red over White]

Just a small nit to pick. The clove in a hefewizen (4-vinyl guaiacol) is a phenol (not an ester), and doesn't (to my knowledge) depend on any particular sugar profile. But it is a function of available ferulic acid, which can be increased by doing an acid rest.

A very valid point, my economy of words often gets me in trouble. Thanks for pointing that out.

 

[Brewsmith]

Can I interject a little here?

You say you are fairly new to brewing. May I ask how new? How many beers have you successfully made? Between this post and others I know you are asking for advice and as much information as you can acquire, but my impression is that your brain is going in a hundred directions at once and you don’t know where to start.

You say you have a temperature controlled fridge, but 60 is the temp, but the freezer is the fridge. You want NEIPAs but are talking about lagers and Cal Common yeast.

If you have a temperature controlled fridge, why pressure ferment? The general purpose of pressure fermentation is to reduce ester production usually at higher fermentation temperatures, yet you are concerned about not having enough esters.

My advice would be to make whatever beer you want and ferment it temperature controlled at the proper temp for that yeast. Get your process down and get all of the variables of brewing under control. At that point if esters are still not where you want, use the control dials of the brewing process to make adjustments. Fermentation temperature, yeast strain, mash schedule, hop varieties, hop amounts, dry hopping, pitching rate, and fermentation pressure.

I’m not trying to be a jerk or even tell you what to do. Brewing can be complicated and pressure fermentation is not a place most brewers jump into right away. If geeking out with the equipment and data is something you are into, then great. I applaud it. My impression is that you have acquired a ton of brewing information, and don’t quite know how to make sense of it all, or be able to tell the difference between important details, secondary concerns, and the minutiae of all the available info.

Most of all, I just want to be helpful, and help you make the best beer possible.

 

[Djangotet]

Can I interject a little here?

You say you are fairly new to brewing. May I ask how new? How many beers have you successfully made? Between this post and others I know you are asking for advice and as much information as you can acquire, but my impression is that your brain is going in a hundred directions at once and you don’t know where to start.

You say you have a temperature controlled fridge, but 60 is the temp, but the freezer is the fridge. You want NEIPAs but are talking about lagers and Cal Common yeast.

If you have a temperature controlled fridge, why pressure ferment? The general purpose of pressure fermentation is to reduce ester production usually at higher fermentation temperatures, yet you are concerned about not having enough esters.

My advice would be to make whatever beer you want and ferment it temperature controlled at the proper temp for that yeast. Get your process down and get all of the variables of brewing under control. At that point if esters are still not where you want, use the control dials of the brewing process to make adjustments. Fermentation temperature, yeast strain, mash schedule, hop varieties, hop amounts, dry hopping, pitching rate, and fermentation pressure.

I’m not trying to be a jerk or even tell you what to do. Brewing can be complicated and pressure fermentation is not a place most brewers jump into right away. If geeking out with the equipment and data is something you are into, then great. I applaud it. My impression is that you have acquired a ton of brewing information, and don’t quite know how to make sense of it all, or be able to tell the difference between important details, secondary concerns, and the minutiae of all the available info.

Most of all, I just want to be helpful, and help you make the best beer possible.

Yeah you are right about that, I am all over the place. Part of it is that I’m trying to find a style that will work perfectly for my setup which happens to be really difficult.

I am basically trying to find one style that I can brew really well without any issues so I can learn. I was really interested in NEIPAS but I can’t get it up to the higher end where it needs to be. I was thinking of doing a hybrid which has a low enough primary temp that I can control the high end of the range without it also taking forever. I can only make 2 gallons at a time so I need a quick turn around. The reason I’m struggling is that:

1. I cannot control temps above 60-65 ambient
2. I can only make 2 gallons at a time so I don’t want to make lengthy beers or I can’t brew that entire time
3. I have all the gear I need to make really high quality beer in a very specific range and I’m trying to figure out what those beer styles are so I can focus and learn from them
4. I don’t have a ton of money so it’s cheaper to read and build recipes right now than to make stuff. Also, since I can only make 2 gallons I’m basically committed once I start

Ideally I would find 2-3 styles that work in that temp range (d rest included), that I enjoy making, and that don’t take a very long time to ferment so I can make more beers. I have made 3 beers and 2 of them were drain pours. I think I nailed the last one I did since all my research seriously improved my setup.

 

[Brewsmith]

That helps but I’m still confused on fermentation temperature control. Can you explain the setup/fridge situation a little better?

 

[Djangotet]

That helps but I’m still confused on fermentation temperature control. Can you explain the setup/fridge situation a little better?

I live in an apartment where utilities are included so my landlord won’t allow me to get a small fridge or anything. I’m using my actual fridge where I store my food. I put the temp reader in the fridge portion so when the fridge goes below 60 degrees the entire unit shuts off. The freezer doesn’t run when the fridge turns off so the top freezer portion ends up between 32 - 40f. If I set my fridge any higher for a d rest all my food will go bad lol.

 

[Djangotet]

I live in an apartment where utilities are included so my landlord won’t allow me to get a small fridge or anything. I’m using my actual fridge where I store my food. I put the temp reader in the fridge portion so when the fridge goes below 60 degrees the entire unit shuts off. The freezer doesn’t run when the fridge turns off so the top freezer portion ends up between 32 - 40f. If I set my fridge higher for a d rest all my food will go bad lol. Room temp is about 70 degrees so it doesn’t take much to make my fridge just stay off.

I think i'm just out of luck. Since pressure fermentation works, I could probably get some used 6 gallons kegs to do that at room temp. I hear that it leaves a sulfur taste but at the end of the day I don't see the stars lining up here.

 

[Brewsmith]

And what type of fermentation vessel is it? Glass? Plastic? Stainless?

 

[Djangotet]

And what type of fermentation vessel is it? Glass? Plastic? Stainless?

I have a set of 2.5 gallon corny kegs. I also have a spunding valve. I was planning to set the valve on the empty keg and purge it with fermentation gas then lager in that one after primary with a closed transfer. I can easily fit some 6 gallon ones in there too but I gotta save up for those. I just wanna figure out what beer style works for me. It's probably better to fine tune with smaller batches anyways.

 

[Brewsmith]

If you are fermenting in a 2.5 gallon corny keg and the fridge isn’t an option, have you considered using a water bath around the keg? I’d get a big bucket or one of those tubs that people use to serve beverages at parties. I’d get the keg in the bath and use frozen water bottles to regulate the water temperature. You can easily keep the temp in the 60s that way. It might take a little trial and error, but I bet you can rig something that is pretty temp stable for cheap. You can even test the temperature without fermenting anything.

Party tub, floating thermometer and reusable water bottles you swap out in the freezer. That’s doable on the cheap

 

[Djangotet]

If you are fermenting in a 2.5 gallon corny keg and the fridge isn’t an option, have you considered using a water bath around the keg? I’d get a big bucket or one of those tubs that people use to serve beverages at parties. I’d get the keg in the bath and use frozen water bottles to regulate the water temperature. You can easily keep the temp in the 60s that way. It might take a little trial and error, but I bet you can rig something that is pretty temp stable for cheap. You can even test the temperature without fermenting anything.

Party tub, floating thermometer and reusable water bottles you swap out in the freezer. That’s doable on the cheap

I thought about it but the floors are wood so the water is super sketchy. I can use my fridge but I just can’t set it above 65f max. I thought about just pulling it out to room temp for the d rest, that might work too.
I don’t think there is necessarily an ideal option for me right now. I am 100% making a kolsch this weekend though, I made my starter already. I can probably turn one around in 3 weeks with pressure. Once I upgrade my keg sizes the time waiting will be worth it. In the mean time, hybrid lagers are probably the cleanest styles I can make.

 

[Brewsmith]

65 works for most ales. I think your biggest hurdle right now should be clean fermentation without contamination. Get sanitation down cold, and if you can do that at 65 in a fridge, you should be on your way to great beer.

 

[Djangotet]

65 works for most ales. I think your biggest hurdle right now should be clean fermentation without contamination. Get sanitation down cold, and if you can do that at 65 in a fridge, you should be on your way to great beer.

Thanks I hope so, my last beer went exactly as planned. That’s a far cry from where I started. I’ll just have to find something simple without all the wild fermentation schedules I see around.

 

[Brewsmith]

Information overload.

Brewing is more forgiving than people think sometimes. Fermenting 2 degrees warmer isn’t going to result in rocket fuel, and 2 degrees colder doesn’t end up with a complete lack of esters.

Do the kolsch at 60. If 65 is as high as you can get for regular ales, then do it and see what happens.

 

[murphyslaw]

Using your kitchen fridge strikes me as a bad solution.

Isn't the point of pressure fermentation to be able to ferment hot? Why use the fridge at all then?

Before I had a spare fridge, I did the bucket method and the t-shirt method. Both seem preferable to turning my kitchen fridge to 60*. Just my 2 cents. Controlling Fermentation Temperature - Brew Your Own

 

[NSMikeD]

60* is inviting problems with the food in your fridge. That’s inside the bacteria zone. Keep your fridge at or below 40*.

If your apartment limits your ability to control temps, make it easier for you by using a yeast that is highly tolerant:

Experiment with Kveik ale yeast. It is very temperature tolerant. At higher temps it will be more fruity and at lower temps dry. Room temperature should result in a neutral profile.

Users have said you need to run long cooler mashes (60-90 min @ 149*) to convert sugars Kveik doesn’t ferment to maltose. Also plenty of oxygen and yeast nutrition.