Lager yeast temp change rate?

[farmskis]

When changing the temps with lager yeast what rate of change is a good rate? 2 degrees per day? 1 degree per hour?

 

[jekeane]

I used to subscribe to the few degrees a day now I do it in 8-10 degree chunks. And the only reason I don't do it all at once is just to avoid sucking all my star san into the fermenter from the pressure change.

I ferment for 4-5 days at 48 another 4-5 days at 50 then let it rise to 68 which in fl takes a day or so. Leave it there for a week and then I do 8 or so degree s down in the am and again at night until its at 32. The crash down to 32 time takes 2 days for me. Then I add gelatin for 3 days or till I have time to keg.

 

[schematix]

8-10F/day is effectively a cold crash and will put your yeast dormant.

Traditional lagering is more like 1-2F per day starting at a bit past halfway. By the time you reach 30F you should be within a few points of FG and the yeast will take care of it slowly over the weeks of lagering.

Diacetyl rests are a crutch for under pitching or poor fermentation control. If pitched properly it's an unnecessary step. I used to do this and can confirm it does produce reasonably good results, but the traditional lager fermentation profile yields a smoother cleaner beverage IMHO.

 

[jekeane]

8-10F/day is effectively a cold crash and will put your yeast dormant.

I dont disagree with this i believe there is plenty of writing out there and anecdotal home brewing experience suggesting that the only point of lagering is to drop the yeast out of suspension.

I also agree that a rest isn't necessarily needed if pitch rate and yeast management is done well. However if you are doing a d rest as most people do then fermentation will be done at the end of that rest and cold crashing the yeast out of suspension is irrelevant.

I tend however, to subscribe because of my own experience, to the idea that lagers can easily be clean clear and servable within a month using quicker methods, However they can also improve with time spent lagering. Not from yeast doing work but from changes in the malt/hop character and continued dropping out of yeast from the beer.

 

[schematix]

I dont disagree with this i believe there is plenty of writing out there and anecdotal home brewing experience suggesting that the only point of lagering is to drop the yeast out of suspension.

There's more to lagering than just dropping out yeast. In a home brewing sense it's kind of like an extended cold crash. But if done in more traditional methods the yeast are still active and additional metabolism takes place that result in what is generally considered to be a superior product.

Having practiced 'home brew' methods like what was described previously, I can confirm satisfactory results. But i will also strongly suggest there are other methods out there that actually give even better results, and will more closely resemble commercial offerings.

I am all for promoting HB lagers though. I think there's a lot more potential finesse for a brewer to showcase in lagers than in ales. There's a reason why lagers are the most popular beers in the world. Even moderately well executed lagers are better than most ale home brewers can produce.

 

[farmskis]

8-10F/day is effectively a cold crash and will put your yeast dormant.

Traditional lagering is more like 1-2F per day starting at a bit past halfway. By the time you reach 30F you should be within a few points of FG and the yeast will take care of it slowly over the weeks of lagering.

Diacetyl rests are a crutch for under pitching or poor fermentation control. If pitched properly it's an unnecessary step. I used to do this and can confirm it does produce reasonably good results, but the traditional lager fermentation profile yields a smoother cleaner beverage IMHO.

Reading this I gather that I should pitch at around 50 hold it there until about halfway finished then begin a slow drop down to 30 and hold it there through lagering. Does it hurt to lager on the dropped yeast? Or are you racking to a secondary then lagering? I am not concerned about time... I think good things come from a little patience. I am planning a German pils, using wlp830.

 

[schematix]

My standard 1.050 lager process goes something like this.

Pitch and oxygenate around 45F. Set (cooling only) controller to 48F and allow to naturally rise over 1-2 days. Hold at 48F until 45% AA is reached (approx 1.028), usually 5-7 days from pitching. Then begin to drop 2F per day until the beer is 6 points above FG (usually 1.012-1.016; do an FFT test!), so i'm looking for 1.018-1.022. That's usually about 3-4 days later and so i'll be around 40-42F. At that point i'll rack to the serving keg, seal the lid with about 5 psi, then hold another week at that same temperature to let the beer finish, carbonate, and consume any oxygen picked up during racking. Then i'll take it down at 2F per day until i hit storage temperature, where it'll stay for at least 2-3 more weeks. Pilsners are extremely drinkable by that point.

Racking with fermentable extract left and naturally carbonatign in the keg has made my lagers much better. Not only is the carbonation better, but the flavor of the beer stays fresher much longer.

 

[farmskis]

My standard 1.050 lager process goes something like this.

Pitch and oxygenate around 45F. Set (cooling only) controller to 48F and allow to naturally rise over 1-2 days. Hold at 48F until 45% AA is reached (approx 1.028), usually 5-7 days from pitching. Then begin to drop 2F per day until the beer is 6 points above FG (usually 1.012-1.016; do an FFT test!), so i'm looking for 1.018-1.022. That's usually about 3-4 days later and so i'll be around 40-42F. At that point i'll rack to the serving keg, seal the lid with about 5 psi, then hold another week at that same temperature to let the beer finish, carbonate, and consume any oxygen picked up during racking. Then i'll take it down at 2F per day until i hit storage temperature, where it'll stay for at least 2-3 more weeks. Pilsners are extremely drinkable by that point.

Racking with fermentable extract left and naturally carbonatign in the keg has made my lagers much better. Not only is the carbonation better, but the flavor of the beer stays fresher much longer.

Thank you for sharing! Couple questions, FFT test? I can test gravity by pulling a sample but I'm not sure what the FFT acronym is.

Also when naturally carbing... Are you going for an exact carb level or are you just getting some carbonation in the beer and fine tuning with co2?

 

[schematix]

Thank you for sharing! Couple questions, FFT test? I can test gravity by pulling a sample but I'm not sure what the FFT acronym is.

Also when naturally carbing... Are you going for an exact carb level or are you just getting some carbonation in the beer and fine tuning with co2?

FFT = fast ferment test or forced ferment test. It's the test you do to accelerate the fermentation on a sample so you know what your FG is going to be. This allows you to time the racking to the serving keg.

The easiest way i've found to do this is to pull a 200mL sample of wort once fermentation starts and run it on a stir plate at room temp for 1-2 days until its done. Then check the gravity with a hydrometer... that way you know where you're going to end (or at least within a point or two).

If you rack with 4-6 points left you're going to end up with ~2.5 volumes. You can use a spund valve to really dial it in, but i find they are more hassle than they are worth.

What i find easier to do though is to manually bleed any excess pressure in event that happens. I'll just check the pressure every few days (it changes slowly) and if its too high i'll bleed the excess pressure off via the PRV. You'll want to build a gas QD + pressure gauge contraption for this purpose. It's very simple and cheap to build.

If i'm low then the bottle CO2 will bring it up during the first few days it's on tap. I've only had it really far off one time and that was my mistake for racking too close to FG with too much head space in the keg.

 

[farmskis]

FFT = fast ferment test or forced ferment test. It's the test you do to accelerate the fermentation on a sample so you know what your FG is going to be. This allows you to time the racking to the serving keg.

The easiest way i've found to do this is to pull a 200mL sample of wort once fermentation starts and run it on a stir plate at room temp for 1-2 days until its done. Then check the gravity with a hydrometer... that way you know where you're going to end (or at least within a point or two).

If you rack with 4-6 points left you're going to end up with ~2.5 volumes. You can use a spund valve to really dial it in, but i find they are more hassle than they are worth.

What i find easier to do though is to manually bleed any excess pressure in event that happens. I'll just check the pressure every few days (it changes slowly) and if its too high i'll bleed the excess pressure off via the PRV. You'll want to build a gas QD + pressure gauge contraption for this purpose. It's very simple and cheap to build.

If i'm low then the bottle CO2 will bring it up during the first few days it's on tap. I've only had it really far off one time and that was my mistake for racking too close to FG with too much head space in the keg.

Thank you for the info!
I don't use a stir plate but I would imagine that leaving it at room temp for a day or so longer would do the same thing.

Is there a reason you can not pull the sample just after pitching and aerating the yeast? Do you need the yeast to populate in the big batch? Or maybe it is because the yeast in the small sample will not be as plentiful and therefore would finish the small sample at a different fg?

 

[farmskis]

My standard 1.050 lager process goes something like this.

Pitch and oxygenate around 45F. Set (cooling only) controller to 48F and allow to naturally rise over 1-2 days. Hold at 48F until 45% AA is reached (approx 1.028), usually 5-7 days from pitching. Then begin to drop 2F per day until the beer is 6 points above FG (usually 1.012-1.016; do an FFT test!), so i'm looking for 1.018-1.022. That's usually about 3-4 days later and so i'll be around 40-42F. At that point i'll rack to the serving keg, seal the lid with about 5 psi, then hold another week at that same temperature to let the beer finish, carbonate, and consume any oxygen picked up during racking. Then i'll take it down at 2F per day until i hit storage temperature, where it'll stay for at least 2-3 more weeks. Pilsners are extremely drinkable by that point.

Racking with fermentable extract left and naturally carbonatign in the keg has made my lagers much better. Not only is the carbonation better, but the flavor of the beer stays fresher much longer.

If I was not going to naturally carb the beer... I would just hold it in the fermenter one more step in your process? Instead of racking to serving keg a few points above I could rack at finished og and then drop the temp like you do to lager and co2 carb?

 

[schematix]

Thank you for the info!
I don't use a stir plate but I would imagine that leaving it at room temp for a day or so longer would do the same thing.

Is there a reason you can not pull the sample just after pitching and aerating the yeast? Do you need the yeast to populate in the big batch? Or maybe it is because the yeast in the small sample will not be as plentiful and therefore would finish the small sample at a different fg?

It would work without a stir plate too, it would just take longer.

The reason you pull the sample after fermentation is started is mainly to ensure you have yeast in your sample and its similar in concentration to the main wort. There are a lot of ways to do it.... i just find this way to be easiest and you're guaranteed a wort sample with enough yeast in it.... and it's active already.

If I was not going to naturally carb the beer... I would just hold it in the fermenter one more step in your process? Instead of racking to serving keg a few points above I could rack at finished og and then drop the temp like you do to lager and co2 carb?

I would strongly recommend naturally carbonating the beer. Much benefit with little downside. What's your apprehension?

 

[Denny]

It really doesn't matter all that much what rate you use. See my recent article in BYO for 3 different methods.

 

[Paulaner]

For your fast ferment test, for me at least I find it easiest to take a gravity sample, save it, pitch the yeast from your flask and simply pour the gravity sample into the flask making use of the leftover yeast in the flask and place it in a hot area of your house. Within 2 days it's fermented out completely and no wasted beer.

 

[farmskis]

It really doesn't matter all that much what rate you use. See my recent article in BYO for 3 different methods.

I would like to read this but in searching the site I am not sure where or what to search to find it.

 

[farmskis]

I would strongly recommend naturally carbonating the beer. Much benefit with little downside. What's your apprehension?

Really none. I definitely am going to do it. I just still need to build the pressure gauge to monitor. to be honest it seems like a win win... Better beer and less co2 use. Let the little yeasts do it all!

 

[farmskis]

For your fast ferment test, for me at least I find it easiest to take a gravity sample, save it, pitch the yeast from your flask and simply pour the gravity sample into the flask making use of the leftover yeast in the flask and place it in a hot area of your house. Within 2 days it's fermented out completely and no wasted beer.

This seems like an easier method for me. Thanks for the technique!

 

[schematix]

For your fast ferment test, for me at least I find it easiest to take a gravity sample, save it, pitch the yeast from your flask and simply pour the gravity sample into the flask making use of the leftover yeast in the flask and place it in a hot area of your house. Within 2 days it's fermented out completely and no wasted beer.

This is what I used to do and it is a completely workable method as well.

Even another option is to ferment right in the hydrometer tube.

 

[farmskis]

It would work without a stir plate too, it would just take longer.

The reason you pull the sample after fermentation is started is mainly to ensure you have yeast in your sample and its similar in concentration to the main wort. There are a lot of ways to do it.... i just find this way to be easiest and you're guaranteed a wort sample with enough yeast in it.... and it's active already.



I would strongly recommend naturally carbonating the beer. Much benefit with little downside. What's your apprehension?

Just curious... Is the carbing with the last few gravity points to get the 2.5 volume just trial and error or is there a resource out there to find these numbers? I find alot on using priming sugar to carbonate but I like your method better and just was trying to read up on it. I like how you're method does it at lagering temp and is built essentially into the process vs adding another step.
Also when watching the pressure do you just keep it at the pressure for current lagering temp for the volume you are desiring? Will this method work if there is headspace in the keg?

 

[schematix]

Just curious... Is the carbing with the last few gravity points to get the 2.5 volume just trial and error or is there a resource out there to find these numbers? I find alot on using priming sugar to carbonate but I like your method better and just was trying to read up on it. I like how you're method does it at lagering temp and is built essentially into the process vs adding another step.
Also when watching the pressure do you just keep it at the pressure for current lagering temp for the volume you are desiring? Will this method work if there is headspace in the keg?

Naturally carbonating is a well established process with calculations tools out there (see: google). Some of those tools take into account other variables such as head space and temperature/pressure of the beer when you cap it (because there is dissolved CO already).
The pressure you need is going to be a function of the temperature you're at and volumes you want.

For example if you want 2.5 volumes and you're holding the keg at 65F, you're going to need 27-28 PSI. Conversely if you're lagering at 30F you only need 7 PSI. If all fermentable extract has been consumed you can freely change the temperature of the keg and the volumes of carbonation won't change, but the pressure will reach a new equilibrium.

There is more to it than I've mentioned, with room for further optimization, but it can also be made into a rule-of-thumb process for simplicity. As long as you have more than enough fermentable sugar remaining to give you the required amount of CO2 you just need to vent the excess pressure, either via a spund, or just by monitoring and burping the PRV. My spund valves have a micro leak that bleeds too much off so i just monitor and burp if required.

 

[Denny]

I would like to read this but in searching the site I am not sure where or what to search to find it.

It;s new enough that it may not be on the website yet.

 

[farmskis]

For example if you want 2.5 volumes and you're holding the keg at 65F, you're going to need 27-28 PSI. Conversely if you're lagering at 30F you only need 7 PSI. If all fermentable extract has been consumed you can freely change the temperature of the keg and the volumes of carbonation won't change, but the pressure will reach a new equilibrium.

So if I am lagering at 30 and sealed it up a couple of points above the fg I should watch the pressure gauge and it should roughly stay around the 7psi for the desired 2.5 voulme? I know when force carbing I would hold it at 7 psi if at 30 degrees and was just curious if I should be looking for the same pressure when using the technique you mentioned. Thanks for bearing with me on the questions!

 

[farmskis]

It;s new enough that it may not be on the website yet.

That could explain it... I will keep my out. Thanks

 

[schematix]

So if I am lagering at 30 and sealed it up a couple of points above the fg I should watch the pressure gauge and it should roughly stay around the 7psi for the desired 2.5 voulme? I know when force carbing I would hold it at 7 psi if at 30 degrees and was just curious if I should be looking for the same pressure when using the technique you mentioned. Thanks for bearing with me on the questions!

Assuming you have a good seal (you'll need to put about 3-5 psi of tank CO2 in initially), the pressure will continue to rise as the last remaining fermentable extract is converted to alcohol and CO2.

You need to determine the pressure required to get the CO2 vols you want based on the temperature it's at. It is as simple as not letting the pressure exceed that.

This is a fairly slow process, especially in lagers. You will probably only need to check every other day unless you reach your limit, and then can burp it once a day until it no longer shows signs of fermentation. If the pressure hasn't changed after a few consecutive readings (i'd give it at least a week) then you've reached terminal gravity.

You can do this process to an ale too but i find they carbonate *much* faster and if you exceed your desired pressure you need to burp them several times a day.

 

[farmskis]

Assuming you have a good seal (you'll need to put about 3-5 psi of tank CO2 in initially), the pressure will continue to rise as the last remaining fermentable extract is converted to alcohol and CO2.

You need to determine the pressure required to get the CO2 vols you want based on the temperature it's at. It is as simple as not letting the pressure exceed that.

This is a fairly slow process, especially in lagers. You will probably only need to check every other day unless you reach your limit, and then can burp it once a day until it no longer shows signs of fermentation. If the pressure hasn't changed after a few consecutive readings (i'd give it at least a week) then you've reached terminal gravity.

You can do this process to an ale too but i find they carbonate *much* faster and if you exceed your desired pressure you need to burp them several times a day.

Thank you! On a side note... Do you natural carb ales? What is your method on this?

 

[schematix]

Thank you! On a side note... Do you natural carb ales? What is your method on this?

Yes.

If the recipe calls for dry hops I add them to the keg with 4-6 points remaining. This is to scavenge any oxygen introduced by the dry hops. A few days later the beer will be at FG and the dry hops will have given their all. I then add the priming liquid solution into the primary through the PRV hole with a funnel and wait until fermentation restarts (~1 hour). Then i rack via the usual process. If the beer reached FG then i would follow this process as well.

If there are no dry hops and i catch the beer with 4-6 points remaining then i rack as usual.

 

[farmskis]

Yes.

If the recipe calls for dry hops I add them to the keg with 4-6 points remaining. This is to scavenge any oxygen introduced by the dry hops. A few days later the beer will be at FG and the dry hops will have given their all. I then add the priming liquid solution into the primary through the PRV hole with a funnel and wait until fermentation restarts (~1 hour). Then i rack via the usual process. If the beer reached FG then i would follow this process as well.

If there are no dry hops and i catch the beer with 4-6 points remaining then i rack as usual.

After adding the priming sugar what temp do you hold the keg at when carbonating? I assume the same temp you have been fermenting at? It sounds like in either case you make sure you have some activity before keeping.

 

[schematix]

After adding the priming sugar what temp do you hold the keg at when carbonating? I assume the same temp you have been fermenting at? It sounds like in either case you make sure you have some activity before keeping.

Room temp for ales (65-75) and lager temps (45-50) for lagers.

Lagers can be fiddled with a little more but the ale yeast goes dormant too easily if it gets cool.

 

[farmskis]

Room temp for ales (65-75) and lager temps (45-50) for lagers.

Lagers can be fiddled with a little more but the ale yeast goes dormant too easily if it gets cool.

With the ales... Do you find that they clear well? I know some swear that cold crashing is required to clear them. I have done this in the past but I think that if trying to carbonate I want to leave the yeast in and not cold crash. I appreciate the info you have provided!

 

[schematix]

With the ales... Do you find that they clear well? I know some swear that cold crashing is required to clear them. I have done this in the past but I think that if trying to carbonate I want to leave the yeast in and not cold crash. I appreciate the info you have provided!

I never have issues with clarity, but i do quite a few things on the hot side to ensure it. The wort that goes into my fermenters is crystal clear. I also use yeast strains that normally flocc well (no hefe for me).

You're going to get some yeast into the serving keg but it'll be minimized if you bend or cut the dip tube in the FV. A little won't hurt... you don't want to transfer the whole cake obviously. Let the beer carbonate, then do your 'cold crash'.

My opinion is that 'cold crashing' is a crutch for other process weaknesses. It's popular because it's easy to do and it'll does help clear a beer. But there are other things that'll accomplish the same thing too. The only 'cold crash' i do is lagering, or when ale carbonation is done and i move the beer to cold storage. It is performed after the transfer to the serving keg, not before.

 

[farmskis]

I think I am going to give it a go with the current brew I have sitting in the primary now.... I won't catch it a few points above finishing but I think I will just let it finish out then rack it over to the serving keg and prime with some sugar and let it sit at room temp until it is carbonated. Then hook it up and serve it.
I have a relatively small co2 tank and I think that carbing my beers with it drains it fast. It's not the money I have to pay for it but more the distance I have to go to get it. plus you have stated some good benefits.