Pilsner Pressure Ferment and at Lager Temps?

[LiamRick]

Hey guys, cant seem to find the answer to this question so thought id ask.

I was originally just going to do entire fermentation controlled at 10°c and wait it out, but then decided why not pressure ferment too.

My question is, is this harmful? Overkill, Unnecessary? Or actually good practice?

also, any idea on fermentation times? Should i ramp up temps at some point or keep it consistent at 10 until i reach my FG. I'm fine with waiting, more about getting a great tasting Czech Pilsner.

Using Diamond Lager Yeast which recommends all fermentations be pitched and controlled around 10 - 15, i cant see anywhere on their info about pressure fermentation's though although i have read people using it for pressure fermenting at ale temps.

Be good to hear all sides, anecdotally and objectively.
Thanks in advance,

additional q, does this look too dark for a czech pils? allbeit its only day 1

 

[IslandLizard]

How are you regulating (maximizing) the pressure in the fermenter?
Is there a spunding valve somewhere that I'm not seeing?

additional q, does this look too dark for a czech pils? allbeit its only day 1

It does seem a little dark, but only after it's done fermenting, poured into a drinking glass, can you judge color.

also, any idea on fermentation times? Should i ramp up temps at some point or keep it consistent at 10 until i reach my FG.

You can nudge it up a few degrees when fermentation starts to slow down, to help keep her engaged.
If you're planning a diacetyl rest you can probably catch both at the same time.

 

[dmtaylor]

Fermenting cold AND pressure fermenting at the same time are misapplication. You'll be creating conditions that are undesirable to the yeast cells and they'll produce even more sulfur and diacetyl, and potentially autolysis. No thanks. But also... go ahead and experiment with it and see what you get.

Color looks OK but it's also difficult to say based on the lighting, etc.

 

[SFC Rudy]

The only hard rule about pressure fermentation is there are no hard rules, at least that I can find. It’s a pro brewing process used to speed up production and move product that people are trying to adapt to the home brewing level.

That being said I’ve done it twice, a Pilsner and a Vienna lager. Started both cold and let the temp and pressure rise. Only real benefits I see is the beer is carbonated and no oxygen transfer to a keg.

 

[Willy]

Depending on which fermenter I am using for a pilsner - sometimes I do pressure fermenting as follows

Let it blow off into a starsan mason for the first 4-5 days. Get most of the conversion done. After a week I add a little pressure (and yes I have a prv style spunding valve on a triclamp. ). Psi around 7-10... Nothing too heavy. Just getting it a start on carbing. I have plenty of time to carb it while lagering in cold storage.

 

[HighVoltageMan!]

Fermenting cold AND pressure fermenting at the same time are misapplication. You'll be creating conditions that are undesirable to the yeast cells and they'll produce even more sulfur and diacetyl, and potentially autolysis. No thanks. But also... go ahead and experiment with it and see what you get.

Color looks OK but it's also difficult to say based on the lighting, etc.

I have to completely disagree with you on this. It certainly is not a misapplication and is in fact beneficial to the end product. I have been doing this for years with none of the downsides you mentioned.

The pressure mimics taller fermenters which have natural hydrostatic pressure. This extra pressure allows taller fermenters to trap excess co2 in solution. The effects of co2 in solution is well known to cause the yeast to produce lower esters and fewer higher alcohols. They do not produce more sulfur, but under pressure the yeast will produce more diacetyl. This is balanced out because the yeast reduce diacetyl faster when under pressure, so in effect, there is no difference in the end.

Pressure slows down fermentation and yeast growth, which is believed to produce cleaner beer. You can warm the beer up to speed up the process, but I believe it's better at lower temperatures (I reserve the right to change my mind on this in the future).

The reason I started fermenting lagers under pressure at lager temperatures was that I was getting a white grape with Wyeast 2124 and a lemon character with Fermentis 34/70. I eliminated this fruitiness and have not had it since I began this practice. I ferment 2124 @ 48F at 7.5 psi and toward the end I raise the pressure and temp until it has hit 60F @ 25psi. 34/70 does not do very well under 50F and it's better at 52F @ 7.5 psi. Both are treated the same toward the end. Plus the beer is fully carb'd at the end of fermentation.

The first beer I made like this was a German Pils with won a 2nd BOS in Milwaukee. It's all in what you want from your beer. I suppose you could raise temperature, but keep in mind the pressure needs to increase to keep the same amount of co2 in solution.

 

[fluketamer]

this thread is bound to get a multitude of replies. . with your setup the best results i have had are to use 34/70. ferment less than 62 degrees. then spund at the end. i have also had excellent results by fermetning and serving in the pressure fermenter. unfortunately for me i have not had as good results pressure fertemtning at higher temps as i have at lower temps without pressure. .

from most of what i have read pressure fermetning occurs because of the height of commercial fermenters casuign a higher pressure at the bpottom of the vessel. i have never seen that it is intentionally done by commercial brewers. except when beer is spunded at the end to increase pressure for transfer or carbonation.

the color always gets lighter due to the settling of light dispersing molecules ( palmer how to brew 4th edition)

i would ferment in the upper range of diamond ( not my preffered lager yeast) then spund witht he last few gravity points cold crash etc.

looks good!

 

[Bassman2003]

I agree with High Voltage, pressure opens up some new flavors. But, you need a lot more yeast to successfully pull it off. My SOP these days for IPA is to bring the fermenter up to 2 BAR once I close it up. Yup, 36 PSI and let it go through fermentation at 70F degrees.

Lager comes to life with high pressure too but I would triple (yes I said triple) the amount of yeast you pitch so they do not poop out. You are effectively putting the yeast through a decathlon so they need greater numbers to finish the job.

 

[Dave C01]

Hey guys, cant seem to find the answer to this question so thought id ask.

I was originally just going to do entire fermentation controlled at 10°c and wait it out, but then decided why not pressure ferment too.

My question is, is this harmful? Overkill, Unnecessary? Or actually good practice?

also, any idea on fermentation times? Should i ramp up temps at some point or keep it consistent at 10 until i reach my FG. I'm fine with waiting, more about getting a great tasting Czech Pilsner.

Using Diamond Lager Yeast which recommends all fermentations be pitched and controlled around 10 - 15, i cant see anywhere on their info about pressure fermentation's though although i have read people using it for pressure fermenting at ale temps.

Be good to hear all sides, anecdotally and objectively.
Thanks in advance,

View attachment 876014
additional q, does this look too dark for a czech pils? allbeit its only day 1

I've been using pressure during fermentation for about five years.
Nearly always start with no pressure.
I've not used Diamond Lager Yeast up to now, have used Nova larger yeast, 34/70 and S-189 call without any adverse effects that I could detect.
I like fermenting towards the lower end of recommended temperatures to get the cleanest crispiest lagers.
I start adding pressure via a spunding valve, the same type that you have in the photo at about 2/3 of attenuation. I'm not specifying number of days, I use a Rapt Pill to monitor temperature and gravity.
Towards the end of fermentation I set the pressure relative to the temperature to achieve full carbonation. I use a carbonation calculator for guidance.
If you are concerned about diacetal, do a diacetal rest or add ALDC enzyme when you pitch the
yeast.

 

[LiamRick]

Thanks for all the replies guys, this was the kind of issue i was running into researching the topic 1. theres not set hard and fast rule for pressure ferments 2. it all seems to be anecdotal achievements regarding pressure ferment at low temps.

How are you regulating (maximizing) the pressure in the fermenter?
Is there a spunding valve somewhere that I'm not seeing?


It does seem a little dark, but only after it's done fermenting, poured into a drinking glass, can you judge color.


You can nudge it up a few degrees when fermentation starts to slow down, to help keep her engaged.
If you're planning a diacetyl rest you can probably catch both at the same time.

Yes, theres a blowtie valve in image to the left, not attached to fermenter in the image, but it was attached after photo. Set the PSI to 0, then 15 after 24 hours.

Activity is low, but its also low when i do unpressurized ferments for first couple of days, then goes absolutely nuts.

Diacetyl rest - yes, when? Unsure. Was just going to keep taking readings near the second week, see where were at. But will also nudge it up as we go i think. 10c is the lower range of temps for this yeast so might err on the side of caution.

I agree with High Voltage, pressure opens up some new flavors. But, you need a lot more yeast to successfully pull it off. My SOP these days for IPA is to bring the fermenter up to 2 BAR once I close it up. Yup, 36 PSI and let it go through fermentation at 70F degrees.

Lager comes to life with high pressure too but I would triple (yes I said triple) the amount of yeast you pitch so they do not poop out. You are effectively putting the yeast through a decathlon so they need greater numbers to finish the job.

Yeah i've added 22g (2 packets) the reccomendation was 22- 33, so hmm, might be a slow one, or a low %.

Fermenting cold AND pressure fermenting at the same time are misapplication. You'll be creating conditions that are undesirable to the yeast cells and they'll produce even more sulfur and diacetyl, and potentially autolysis. No thanks. But also... go ahead and experiment with it and see what you get.

Color looks OK but it's also difficult to say based on the lighting, etc.

Whats the rationale behind more sulfur and diacetyl? As mentioned happy to long it out to drive away those sulfer notes (although some Czech Pils i read its nice to have a slight sulfer note). I was hoping the lower temps and longer time & diacetyl rest would eliminate this. As mentioned, why do you think it will add these two things, is it previous brews or factual knowledge?

 

[Bassman2003]

What dm is getting at ties into what I am saying about the number of yeast cells - pressure fermenting does induce stress on the yeast. To overcome this you need a lot more yeast. But through stress comes interesting beer. High pressure reduces a lot of flavors, both good and bad. The wild card variable is temperature. Higher temps result in more ester character being allowed to stay in the final beer. For lager, pressure + cold temps is as clean as it gets. It is a fun thing to experiment with.

As homebrewers, we can only get pressure via CO2. The big breweries get pressure via hydrostatic pressure. The shear size of the tanks give them this hurdle where we can choose how much or little we want. But, CO2 is toxic to yeast and the colder the temps go, the more CO2 winds up in solution. So you see the correlation between warmer temps/more esters/less CO2 vs colder temps/less esters/more CO2 in solution. You just need more yeast to pull of a cold pressure ferment.

 

[LiamRick]

Right got you that makes total sense thanks guys. I think i spend a lot of time researching keeping temps regulated is important - and especially not getting too hot that i rarely thought about the flip side of yeast getting too cold and the stressors in that.

Do you think i should depressurise? or just roll with it and see what happens, ill probably do a second without pressure to compare too.

Is it worth doing a Diacetyl Rest after FG?

Excited to transfer and lager, see what happens, will keep updated

 

[IslandLizard]

Is it worth doing a Diacetyl Rest after FG?

You must do the D-rest before fermentation has completely finished. IOW, there should be a few points of gravity left when you start the D-rest. Otherwise it can't convert the diacetyl.

 

[Bassman2003]

I think i spend a lot of time researching keeping temps regulated is important - and especially not getting too hot that i rarely thought about the flip side of yeast getting too cold and the stressors in that.

Cold is not a stressor for yeast. That was never said.

 

[mac_1103]

As homebrewers, we can only get pressure via CO2. ... But, CO2 is toxic to yeast and the colder the temps go, the more CO2 winds up in solution.

This made me wonder if anyone has tried fermenting under nitrogen pressure. Not that I have any idea what that might accomplish.

 

[Kickass]

I recently listened to a podcast with a Fermintis rep talking about their lager strains. He said, using lab equipment to measure, 34/70 actually produces more esters when fermented on the cooler side of the recommended temp range. Taking that into account I’m of a similar mind set of @dmtaylor. You ferment cold and under pressure, you’re not doing yourself any favors, unless that’s what you want to achieve.

Additionally, why would you want to ferment cold and under pressure if you have to use 3x as much yeast to get a clean flavor profile? To each their own but I’ll continue to ferment my 34/70, and closely related strains, around 60f at 1/3 the yeast cost.

 

[HighVoltageMan!]

I recently listened to a podcast with a Fermintis rep talking about their lager strains. He said, using lab equipment to measure, 34/70 actually produces more esters when fermented on the cooler side of the recommended temp range. Taking that into account I’m of a similar mind set of @dmtaylor. You ferment cold and under pressure, you’re not doing yourself any favors, unless that’s what you want to achieve.

Additionally, why would you want to ferment cold and under pressure if you have to use 3x as much yeast to get a clean flavor profile? To each their own but I’ll continue to ferment my 34/70, and closely related strains, around 60f at 1/3 the yeast cost.

I have been putting 34/70 under pressure for years at lager temperatures with great results. It is definitely cleaner under pressure than without pressure at 50-52F. German breweries have been pressure fermenting for decades. Great Lakes Brewery pressure ferments most of their lagers at elevated temperature, I believe they ferment @ 60F. Just keep in mind that lower temperatures mean lower pressures.

I also disagree with the idea that more than the recommended yeast is necessary. The yeast, especially 34/70, can easily handle pressures up 15 psi with little stress and they can be spunded up to 30 psi. A 1.050 gravity beer can be pitch @ 1 to 1.3 packs per 2.5 gallons with fantastic results. I have actually overpitch 34/70 and it gave a floral rose pedal aroma that wasn't very pleasant.

 

[odie]

You must do the D-rest before fermentation has completely finished. IOW, there should be a few points of gravity left when you start the D-rest. Otherwise it can't convert the diacetyl.

I did not know that. I assumed time just sitting would attenuate any diacetyl? If you are fermenting a little on the warm side do you even need the D-rest? Lagers under pressure allow higher fermentation temps. does that basically eliminate the need for a D-rest?

 

[Bassman2003]

I recently listened to a podcast with a Fermintis rep talking about their lager strains. He said, using lab equipment to measure, 34/70 actually produces more esters when fermented on the cooler side of the recommended temp range. Taking that into account I’m of a similar mind set of @dmtaylor. You ferment cold and under pressure, you’re not doing yourself any favors, unless that’s what you want to achieve.

Additionally, why would you want to ferment cold and under pressure if you have to use 3x as much yeast to get a clean flavor profile? To each their own but I’ll continue to ferment my 34/70, and closely related strains, around 60f at 1/3 the yeast cost.

Do not mistake needing more yeast with pressure to "get a clean flavor profile". One needs more yeast because the environment is difficult and you need more cells to complete fermentation strong. Anything fermented under pressure will be cleaner (fewer esters) than no pressure. The process tends to suppress esters. Lower the temps and you suppress more esters...

Also, do not fall into the trap of high pressure = high temp lagers. I think no pressure but cold fermentation lager is a better approach than pressure but high temp lager. Pressure does cover up some ills, but is a work-around, not best lager practice. This varies a lot in the homebrew world but I think it is important to set baseline best practices on homebrewing forums rather than just 'what people do'.

 

[Bassman2003]

I did not know that. I assumed time just sitting would attenuate any diacetyl? If you are fermenting a little on the warm side do you even need the D-rest? Lagers under pressure allow higher fermentation temps. does that basically eliminate the need for a D-rest?

The yeast do all of the work. If they are done and pooped out no diacetyl will be eaten...

 

[Broothru]

I have to completely disagree with you on this. It certainly is not a misapplication and is in fact beneficial to the end product. I have been doing this for years with none of the downsides you mentioned.

The pressure mimics taller fermenters which have natural hydrostatic pressure. This extra pressure allows taller fermenters to trap excess co2 in solution. The effects of co2 in solution is well known to cause the yeast to produce lower esters and fewer higher alcohols. They do not produce more sulfur, but under pressure the yeast will produce more diacetyl. This is balanced out because the yeast reduce diacetyl faster when under pressure, so in effect, there is no difference in the end.

Pressure slows down fermentation and yeast growth, which is believed to produce cleaner beer. You can warm the beer up to speed up the process, but I believe it's better at lower temperatures (I reserve the right to change my mind on this in the future).

The reason I started fermenting lagers under pressure at lager temperatures was that I was getting a white grape with Wyeast 2124 and a lemon character with Fermentis 34/70. I eliminated this fruitiness and have not had it since I began this practice. I ferment 2124 @ 48F at 7.5 psi and toward the end I raise the pressure and temp until it has hit 60F @ 25psi. 34/70 does not do very well under 50F and it's better at 52F @ 7.5 psi. Both are treated the same toward the end. Plus the beer is fully carb'd at the end of fermentation.

The first beer I made like this was a German Pils with won a 2nd BOS in Milwaukee. It's all in what you want from your beer. I suppose you could raise temperature, but keep in mind the pressure needs to increase to keep the same amount of co2 in solution.

I also will have to completely disagree by completely agreeing, if that makes sense.

Last year I fermented several lagers under pressure, at elevated temperatures: an American Lager (took 1st Place in category), a Kolsch (yeah, kinda like a lager, kinda like an ale, scored 39 points and won 1st Place in category), a Munich Helles (scored 41 points and took Best of Show), and a 'Cold' IPA that was done 'hot' and under pressure (took 3rd Place in a very crowded category, and yes, it's obviously an ale).

All the fermentations were done under 1 BAR pressure from a capped fermentation, at approximately 10F above the highest temperature listed in the data sheets for each yeast. All reached Final Gravity within 4-5 days, followed by diacetyl rests of 3 days at 10F above the fermentation temperatures. Three of the fermentations used NovaLager dry yeast, which isn't advertised as a 'pressurized yeast', yet all seemed quite acceptable to the BJCP certified judges. The odd man out was the 'Cold' IPA which was fermented with White Labs WLP-808 "Mythical Hammer" which is a hybrid lager yeast specifically designed to be used as a pressurized yeast at higher fermentation temperature.

I look at pressurized fermentations as simply an extension of spunding, except capping the fermentation at normal optimum temperature once active fermentation has begun, usually within the first 12-24 hours. Then the fermentation temperature is increased to slightly above the optimum range as the pressure gradually rises to 1 BAR.

I don't do pressurized fermentations all the time. In fact, the last seven batches I've brewed since rehab following my January surgery have all been unpressurized and done within the optimum temperature ranges of the specific yeasts. That doesn't mean that I've given up on fermenting under pressure. Quite the contrary. It's just another tool in the kit box. But I'm yet to find serious flaws in the process. It's a great way to go from grain to glass more quickly, with little to no downside that I've experienced in my efforts to date. I'm sure I'll use the process some more this year when my brewing starts in earnest for the summer competitions.

 

[LiamRick]

Cold is not a stressor for yeast. That was never said.

A Decathalon would be stressful for me for sure.

Anyway, i think im just going to stick at what im doing, taste the results, then do one without pressure.

Thanks for all your input guys will be sure to post any progress

 

[Bassman2003]

The CO2 is the stressor and the cold invites more CO2 into the wort. Cold alone does not stress yeast, it just slows them down.

 

[Bassman2003]

This made me wonder if anyone has tried fermenting under nitrogen pressure. Not that I have any idea what that might accomplish.

It would go well but you would have nitrogen as your carbonation which would be different. I don't think nitrogen is toxic to yeast.

 

[dmtaylor]

It would go well but you would have nitrogen as your carbonation which would be different. I don't think nitrogen is toxic to yeast.

I might be wrong, but I can imagine pouring 100% foam that takes a while to settle. The Czechs might like this?!

 

[HighVoltageMan!]

It would go well but you would have nitrogen as your carbonation which would be different. I don't think nitrogen is toxic to yeast.

You would have to remove the co2 the yeast produced and preserve the nitrogen pressure, probably not possible let alone practical.

 

[Dave C01]

This made me wonder if anyone has tried fermenting under nitrogen pressure. Not that I have any idea what that might accomplish.

I don't know what the result would be, but it wouldn't remove CO2!

 

[mac_1103]

it wouldn't remove CO2

Didn't think it would remove it, but maybe reduce it. Thinking about it more it would obviously require a lot of manual manipulation. As in frequent depressurizing to remove CO2 and repressurizing with nitro.

 

[Bassman2003]

Yes, it would end up in a 'beer gas' type of mixture which might be interesting in the end! If you can get ahold of a nitrogen generator you would be set.

 

[mac_1103]

If you can get ahold of a nitrogen generator you would be set.

Would that basically be the opposite of an oxygen generator?