I froze my lager

[protectivedad]

So, I need some advice. I created a lagering chamber, with a freezer and a temperature relay. I bought the festa brew bock which uses a saflager which recommends 12C for optimal fermentation. I started it at 18C for 2 days then brought it down to 12C. After 10 days I rose it to 18C for to rest for 2 days moved it to a carboy and I was planning on bringing it down to 4C for a month or two. It seems that where I placed the temperature sensor wasn't the best location because it never registered below 10C. Yesterday, I set it to 9C and when I went today to lower it again, my freezer was freezing the temperature gauge said only 11C and my water for an airlock was frozen solid.

What's my plan of attack? The yeast will have gone dorment right? The beer has actually started to freeze a little. Will that have ruined it?

I was going to raise it back to 18 to see if the yeast will get back to work and then try to bring it back down to 4C like I was planning. Any suggestions?

Thanks.

[mr x]

I think the first thing to do is warm it up to 12-18 degrees for a day and take a hydrometer sample.

Sent from my Nexus S

[Tony L]

You did take a hydro sample to make sure you were finished fermenting before you attempted to lager it didn't you?
If not, then take the reading, and if it is within the yeast specs for finishing, then just bring up your temps to about 2 to 3 c and finish lagering.
After all the carboy didn't freeze, so nothing bad happened to the yeast except you put it to sleep a little early.
If you aren't finished fermenting warm that baby up to 18c to let it finish.

[amartin]

If it's done fermenting you're definitely fine. I lager my beer on the back deck, and while I've never had it freeze solid, it does slush on me often enough.

[Jayme]

All the temperature fluctuation is not ideal... Once you've warmed it up and taken a reading, taste it as well. If there's a lot of sulfur and/or diacetyl, it may be difficult to fix given the conditions you described.

Ideally, you should pitch at fermentation temp - 12C by what your saying and not 18C - pitching at 18C will cause the yeast to put out a lot more off flavours at the start, meaning it has to work all that much harder at the end. When fermentation has almost stopped (almost is key - if it has stopped, you're too late), that's your chance to raise the temp up to 18C for a diacetyl rest before racking the beer (I only use one vessel for ales but always do a transfer when lagering). Then crash for lagering at about 10C below your original fermentation temp. Having it freeze at any point is bad for yeast health - while lagering, the yeast is still slowly working to clean up your beer. After lagering is complete, then you can crash it another few degrees to put the yeast to sleep.

Are you using a temperature controller on the freezer?

[protectivedad]

You did take a hydro sample to make sure you were finished fermenting before you attempted to lager it didn't you?
If not, then take the reading, and if it is within the yeast specs for finishing, then just bring up your temps to about 2 to 3 c and finish lagering.
After all the carboy didn't freeze, so nothing bad happened to the yeast except you put it to sleep a little early.
If you aren't finished fermenting warm that baby up to 18c to let it finish.

I mind melded with it and it told me it was about 80% done before I brought it up to rest. Though I admit there might be some chance that my technique isn't 100% accurate.

I guess I'm going to have to by a thief. My wife is going to be on my a$$ for buying new equipment .

[protectivedad]

All the temperature fluctuation is not ideal... Once you've warmed it up and taken a reading, taste it as well. If there's a lot of sulfur and/or diacetyl, it may be difficult to fix given the conditions you described.

Ideally, you should pitch at fermentation temp - 12C by what your saying and not 18C - pitching at 18C will cause the yeast to put out a lot more off flavours at the start, meaning it has to work all that much harder at the end. When fermentation has almost stopped (almost is key - if it has stopped, you're too late), that's your chance to raise the temp up to 18C for a diacetyl rest before racking the beer (I only use one vessel for ales but always do a transfer when lagering). Then crash for lagering at about 10C below your original fermentation temp. Having it freeze at any point is bad for yeast health - while lagering, the yeast is still slowly working to clean up your beer. After lagering is complete, then you can crash it another few degrees to put the yeast to sleep.

Are you using a temperature controller on the freezer?

I bought a LED relay. The problem was I put the sensor under the carboy between the freezer floor and the bottom of the carboy. It seemed to insulate the sensor. I have fixed this problem so I will now get an accurate reading of the air temperature.

I was just starting the fermentation at 18C (to make sure it got a good start) as soon as I saw some activity I started to bring the temps down to the ideal yeast temps. From what I have reads though this specific yeast ferments cleaner at a higher temp (I know this doesn't make very much sense).

I'll go by a thief and test the beer.

[Jayme]

I bought a LED relay. The problem was I put the sensor under the carboy between the freezer floor and the bottom of the carboy. It seemed to insulate the sensor. I have fixed this problem so I will now get an accurate reading of the air temperature.

I was just starting the fermentation at 18C (to make sure it got a good start) as soon as I saw some activity I started to bring the temps down to the ideal yeast temps. From what I have reads though this specific yeast ferments cleaner at a higher temp (I know this doesn't make very much sense).

I'll go by a thief and test the beer.

What exactly do you mean by an LED relay? Those are two separate electronic devices, neither of which can control temperature. Unless you mean a temperature controller that you installed a LED and a relay?

http://www.fermentis.com/FO/pdf/HB/EN/S ... -23_HB.pdf
The recommended temperature range for that yeast is 12-15C. I'm not sure where you read it ferments cleaner at temps higher than that, but I would question the information source. It does say on the info sheet one pitching option is sprinkle directly onto 20C wort and then cool it down - however it has been well established (Jamil comes to mind and I'm pretty sure other leading experts have agreed) that you should never directly pitch yeast into wort without re hydrating. Further to that, Jamil goes to great length explaining exactly why you should not pitch yeast above fermentation temperature and then lower the temperature back down on a few occasions on his show (on the Brewing Network) - I understand what you're saying to get it started and then lower the temp. However that is not best practice. Yes you will still make beer, probably even some good beer. It's the minor details in the end that make the difference between good and great beer though.

[Bryan]

All the temperature fluctuation is not ideal... Once you've warmed it up and taken a reading, taste it as well. If there's a lot of sulfur and/or diacetyl, it may be difficult to fix given the conditions you described.

Ideally, you should pitch at fermentation temp - 12C by what your saying and not 18C - pitching at 18C will cause the yeast to put out a lot more off flavours at the start, meaning it has to work all that much harder at the end. When fermentation has almost stopped (almost is key - if it has stopped, you're too late), that's your chance to raise the temp up to 18C for a diacetyl rest before racking the beer (I only use one vessel for ales but always do a transfer when lagering). Then crash for lagering at about 10C below your original fermentation temp. Having it freeze at any point is bad for yeast health - while lagering, the yeast is still slowly working to clean up your beer. After lagering is complete, then you can crash it another few degrees to put the yeast to sleep.

Are you using a temperature controller on the freezer?

I bought a LED relay. The problem was I put the sensor under the carboy between the freezer floor and the bottom of the carboy. It seemed to insulate the sensor. I have fixed this problem so I will now get an accurate reading of the air temperature.

I was just starting the fermentation at 18C (to make sure it got a good start) as soon as I saw some activity I started to bring the temps down to the ideal yeast temps. From what I have reads though this specific yeast ferments cleaner at a higher temp (I know this doesn't make very much sense).

I'll go by a thief and test the beer.

This may have already been addressed, but the way many people measure the temperature of the beer is as follows: Tape the sensor to the carboy (~halfway up). Get some insulation wrap (bubble wrap or even paper towel will do), and tape that over the sensor. You will then be basically reading the temperature of the beer, and not the air in the freezer.

[protectivedad]

All the temperature fluctuation is not ideal... Once you've warmed it up and taken a reading, taste it as well. If there's a lot of sulfur and/or diacetyl, it may be difficult to fix given the conditions you described.

Ideally, you should pitch at fermentation temp - 12C by what your saying and not 18C - pitching at 18C will cause the yeast to put out a lot more off flavours at the start, meaning it has to work all that much harder at the end. When fermentation has almost stopped (almost is key - if it has stopped, you're too late), that's your chance to raise the temp up to 18C for a diacetyl rest before racking the beer (I only use one vessel for ales but always do a transfer when lagering). Then crash for lagering at about 10C below your original fermentation temp. Having it freeze at any point is bad for yeast health - while lagering, the yeast is still slowly working to clean up your beer. After lagering is complete, then you can crash it another few degrees to put the yeast to sleep.

Are you using a temperature controller on the freezer?

I bought a LED relay. The problem was I put the sensor under the carboy between the freezer floor and the bottom of the carboy. It seemed to insulate the sensor. I have fixed this problem so I will now get an accurate reading of the air temperature.

I was just starting the fermentation at 18C (to make sure it got a good start) as soon as I saw some activity I started to bring the temps down to the ideal yeast temps. From what I have reads though this specific yeast ferments cleaner at a higher temp (I know this doesn't make very much sense).

I'll go by a thief and test the beer.

This may have already been addressed, but the way many people measure the temperature of the beer is as follows: Tape the sensor to the carboy (~halfway up). Get some insulation wrap (bubble wrap or even paper towel will do), and tape that over the sensor. You will then be basically reading the temperature of the beer, and not the air in the freezer.

I have read that, my concern is that the sensor I have has a 1C hysteresis loop. Plus I noticed that if I after the freezer cuts off the chamber continues to cool. So for my setup I end up with a 12C setting causing at least a 12-13 degree on off plus extra cooling of 1 to .5 C below the 12. I was trying to be tricky and find a way to have the relay turn on and off quicker than the 1C to keep the liquid temperature more consistent. I had also heard of putting the sensor in a cup of water in the freezer.

[Bryan]

Here's something I've recently started doing: I have a cheap fridge controller (Johnson), and it has a 4F swing. So, lets say the set-point is 68; when the sensor gets to 68, the fridge will turn on until the sensor reads 64. So, here's my solution: get a case of pepsi (or whatever), and tape the sensor (with insulation) to one of the cans in the case. The case of pop will swing 4F, but the carboy will only swing by 1F. You can fool around with number of cans to reduce the swing in the carboy.

[Jayme]

I have read that, my concern is that the sensor I have has a 1C hysteresis loop. Plus I noticed that if I after the freezer cuts off the chamber continues to cool. So for my setup I end up with a 12C setting causing at least a 12-13 degree on off plus extra cooling of 1 to .5 C below the 12. I was trying to be tricky and find a way to have the relay turn on and off quicker than the 1C to keep the liquid temperature more consistent. I had also heard of putting the sensor in a cup of water in the freezer.

Sounds like you've got one of the cheap Ebay aquarium temperature controllers. There are two models and one of them has 0.3C of hysteresis - it's the better choice but you should still be able to work with the other model. I don't understand why you think it's better to put the thermistor under the carboy given that condition rather than directly on the side of the carboy where it will be very close to the temperature of the beer. Changing that alone I'm quite certain will help. Also, those temperature controllers do not come from the factory calibrated - so the temperature it's reading may not be correct. There is an offset but it goes by degree instead of tenths - still will help if you're more out by more than a degree. Not sure where you read about putting the sensor in a cup of water, but during active fermentation that's a poor choice. Fermentation is exothermic and a still glass of water is not - therefore while the beer is still fermenting, it will not be at the same temperature as the glass of water. If you have a really active fermentation, it is entirely possible the freezer would have to work hard enough that the water will freeze but the beer could still be at 12C (maybe not that extreme, but you can definitely have a fairly substantial differential).

Bottom line, I think you should do as Bryan suggested and tape the thermistor to the side of the carboy, check the calibration of controller, and consider upgrading to the slightly better controller when you can afford to.
http://www.ebay.ca/itm/170905482961?ssP ... 1497.l2649

[Jayme]

Here's something I've recently started doing: I have a cheap fridge controller (Johnson), and it has a 4F swing. So, lets say the set-point is 68; when the sensor gets to 68, the fridge will turn on until the sensor reads 64. So, here's my solution: get a case of pepsi (or whatever), and tape the sensor (with insulation) to one of the cans in the case. The case of pop will swing 4F, but the carboy will only swing by 1F. You can fool around with number of cans to reduce the swing in the carboy.

I could see that working well while lagering since fermentation has slowed to a crawl, but early on during fermentation I don't think that's a great idea.

[Bryan]

Here's something I've recently started doing: I have a cheap fridge controller (Johnson), and it has a 4F swing. So, lets say the set-point is 68; when the sensor gets to 68, the fridge will turn on until the sensor reads 64. So, here's my solution: get a case of pepsi (or whatever), and tape the sensor (with insulation) to one of the cans in the case. The case of pop will swing 4F, but the carboy will only swing by 1F. You can fool around with number of cans to reduce the swing in the carboy.

I could see that working well while lagering since fermentation has slowed to a crawl, but early on during fermentation I don't think that's a great idea.

Agreed... I have picked up the aquarium controller and just need to wire it up. Certainly I should be controlling the beer temperature, just working with what I have for now.

[Jayme]

Agreed... I have picked up the aquarium controller and just need to wire it up. Certainly I should be controlling the beer temperature, just working with what I have for now.

Haha fair enough. That can be both a pain in the ass yet fun all at the same time!

[protectivedad]

I have read that, my concern is that the sensor I have has a 1C hysteresis loop. Plus I noticed that if I after the freezer cuts off the chamber continues to cool. So for my setup I end up with a 12C setting causing at least a 12-13 degree on off plus extra cooling of 1 to .5 C below the 12. I was trying to be tricky and find a way to have the relay turn on and off quicker than the 1C to keep the liquid temperature more consistent. I had also heard of putting the sensor in a cup of water in the freezer.

Sounds like you've got one of the cheap Ebay aquarium temperature controllers. There are two models and one of them has 0.3C of hysteresis - it's the better choice but you should still be able to work with the other model. I don't understand why you think it's better to put the thermistor under the carboy given that condition rather than directly on the side of the carboy where it will be very close to the temperature of the beer. Changing that alone I'm quite certain will help. Also, those temperature controllers do not come from the factory calibrated - so the temperature it's reading may not be correct. There is an offset but it goes by degree instead of tenths - still will help if you're more out by more than a degree. Not sure where you read about putting the sensor in a cup of water, but during active fermentation that's a poor choice. Fermentation is exothermic and a still glass of water is not - therefore while the beer is still fermenting, it will not be at the same temperature as the glass of water. If you have a really active fermentation, it is entirely possible the freezer would have to work hard enough that the water will freeze but the beer could still be at 12C (maybe not that extreme, but you can definitely have a fairly substantial differential).

Bottom line, I think you should do as Bryan suggested and tape the thermistor to the side of the carboy, check the calibration of controller, and consider upgrading to the slightly better controller when you can afford to.
http://www.ebay.ca/itm/170905482961?ssP ... 1497.l2649

I understood everything you mentioned. My thinking was that the freezer chamber is a closed system. At first there will be a difference between the water and beer but the beer will heat the chamber which will transfer to the water, etc. It will all eventually come to some type of equilibrium. So the metal on the inside of the freezer will cool fastest, the air next, the glass carboy and beer last. That's the cooling action. As you mentioned the fermentation creates heat which heats the beer then the glass then the air. No of course there is a temperature gradient from the outside of the beer to the centre. An equilibrium between the two will be established. I was hoping to get the controller to turn off quickly because of the contact with the freezer floor but to be compensated by the heat generated by the beer fermenting. This seemed to work fine to 12C below that it stopped working. I'm guessing the beer fermentation in the centre of the was enough to heat the chamber under the carboy. It would only have gotten to the right temperature after the fermentation had stopped entirely and the outside had started to freeze.

My engineering physics thesis was on temperature gradients in metal to be used as a heat sealing device.

What I need to do I think is drop a floating thermometer and measure the beer temperature as it fluctuates with different sensor setups.

Now back to my beer.

I measured it the OG was ~1.065 the FG is supposed to be ~1.02 and the current gravity is 1.024. Oh and it tasted pretty tasty, though my palate sucks and I've never had a Bock before so what do I know.

What do you think? Just leave it a 4C and let it go?

[protectivedad]

Oh I forgot to compensate due to the temperature for the current gravity. The beer was around 6C when testing so that drops it just a little.

[RubberToe]

FYI I also tape the probe to the side of my most active carboy under a piece of folded towel or paper towel. Also, on all 3 of my ebay STC-1000 the temp calibration and hysteresis are in tenths precision.

I set my chest freezer ferm chamber to 1 or 2 degrees C without freezing my brew (I do that to cold crash).

[Jayme]

I understood everything you mentioned. My thinking was that the freezer chamber is a closed system. At first there will be a difference between the water and beer but the beer will heat the chamber which will transfer to the water, etc. It will all eventually come to some type of equilibrium. So the metal on the inside of the freezer will cool fastest, the air next, the glass carboy and beer last. That's the cooling action. As you mentioned the fermentation creates heat which heats the beer then the glass then the air. No of course there is a temperature gradient from the outside of the beer to the centre. An equilibrium between the two will be established. I was hoping to get the controller to turn off quickly because of the contact with the freezer floor but to be compensated by the heat generated by the beer fermenting. This seemed to work fine to 12C below that it stopped working. I'm guessing the beer fermentation in the centre of the was enough to heat the chamber under the carboy. It would only have gotten to the right temperature after the fermentation had stopped entirely and the outside had started to freeze.

My engineering physics thesis was on temperature gradients in metal to be used as a heat sealing device.

What I need to do I think is drop a floating thermometer and measure the beer temperature as it fluctuates with different sensor setups.

Now back to my beer.

I measured it the OG was ~1.065 the FG is supposed to be ~1.02 and the current gravity is 1.024. Oh and it tasted pretty tasty, though my palate sucks and I've never had a Bock before so what do I know.

What do you think? Just leave it a 4C and let it go?

I'm not going to argue further, but the bottom line is it seems your measurement method didn't work very well, so why not try the method many other people have been successful with? I would say your thesis didn't really help you in this instance and frankly I'm not sure why you felt the need to bring it up. Others have done the exact same test you're talking about and without investing in some real time temperature loggers, I don't think you'll be able to accurately monitor the trends - and if you're going to buy something like that, just spring for a better temp controller. I think there is an episode of Brew Strong where John Palmer and Jamil Zainasheff talk in depth about the topic which may help convince you.

If it tastes ok, I would lager and drink it. Since you like it and you don't have to worry about selling it. If someone else thinks it's shitty, who cares? They don't have to drink it!

Also, if you don't know what a Bock should taste like, try one:
http://premierwines.ca/store/category/2 ... an-Styles/

Maybe you won't even like the taste and prefer your own version!

[Jayme]

Also, on all 3 of my ebay STC-1000 the temp calibration and hysteresis are in tenths precision.

I wish the hysteresis could go as low as 0.1C, though I guess 0.3 is still decent - certainly better than 1C!

[protectivedad]

I understood everything you mentioned. My thinking was that the freezer chamber is a closed system. At first there will be a difference between the water and beer but the beer will heat the chamber which will transfer to the water, etc. It will all eventually come to some type of equilibrium. So the metal on the inside of the freezer will cool fastest, the air next, the glass carboy and beer last. That's the cooling action. As you mentioned the fermentation creates heat which heats the beer then the glass then the air. No of course there is a temperature gradient from the outside of the beer to the centre. An equilibrium between the two will be established. I was hoping to get the controller to turn off quickly because of the contact with the freezer floor but to be compensated by the heat generated by the beer fermenting. This seemed to work fine to 12C below that it stopped working. I'm guessing the beer fermentation in the centre of the was enough to heat the chamber under the carboy. It would only have gotten to the right temperature after the fermentation had stopped entirely and the outside had started to freeze.

My engineering physics thesis was on temperature gradients in metal to be used as a heat sealing device.

What I need to do I think is drop a floating thermometer and measure the beer temperature as it fluctuates with different sensor setups.

Now back to my beer.

I measured it the OG was ~1.065 the FG is supposed to be ~1.02 and the current gravity is 1.024. Oh and it tasted pretty tasty, though my palate sucks and I've never had a Bock before so what do I know.

What do you think? Just leave it a 4C and let it go?

I'm not going to argue further, but the bottom line is it seems your measurement method didn't work very well, so why not try the method many other people have been successful with? I would say your thesis didn't really help you in this instance and frankly I'm not sure why you felt the need to bring it up. Others have done the exact same test you're talking about and without investing in some real time temperature loggers, I don't think you'll be able to accurately monitor the trends - and if you're going to buy something like that, just spring for a better temp controller. I think there is an episode of Brew Strong where John Palmer and Jamil Zainasheff talk in depth about the topic which may help convince you.

If it tastes ok, I would lager and drink it. Since you like it and you don't have to worry about selling it. If someone else thinks it's shitty, who cares? They don't have to drink it!

Also, if you don't know what a Bock should taste like, try one:
http://premierwines.ca/store/category/2 ... an-Styles/

Maybe you won't even like the taste and prefer your own version!

Sorry, you completely misunderstood. I wasn't arguing at all. I know my method for measuring didn't work. That was so obvious it didn't occur to me that anyone would think I would continue with it. I was just mentioning WHY I did it. I have no intention of EVER doing it again. I plan on trying the different techniques mentioned and figure out what works best.

As to the beer, I'd like to get it a close to true as I can given the mistake of over cooling it. Plus, a small taste and going through a whole keg will be a very different experience. I can see a flavour that doesn't bother me in a taste bothering me after the third week of drinking it daily .

Is it too far from the FG? Should I continue until I'm closer? Now that I have the thief I might as well use it.

Thanks.

[Jayme]

Sorry, you completely misunderstood. I wasn't arguing at all. I know my method for measuring didn't work. That was so obvious it didn't occur to me that anyone would think I would continue with it. I was just mentioning WHY I did it. I have no intention of EVER doing it again. I plan on trying the different techniques mentioned and figure out what works best.

As to the beer, I'd like to get it a close to true as I can given the mistake of over cooling it. Plus, a small taste and going through a whole keg will be a very different experience. I can see a flavour that doesn't bother me in a taste bothering me after the third week of drinking it daily .

Is it too far from the FG? Should I continue until I'm closer? Now that I have the thief I might as well use it.

Thanks.

My bad - hopefully if you try the side of the carboy it will work better for you next time.

So you're at about 1.022 right now which is a bit high (http://www.bjcp.org/2008styles/style05.php). Probably not a bad idea to see if you can get it a little lower by leaving it ~18C for a while. If it doesn't doesn't go lower, you might be able to finish it off with a repitch of actively fermenting yeast (could be ale yeast, doesn't matter too much at this stage) or just go with it.

[protectivedad]

Sorry, you completely misunderstood. I wasn't arguing at all. I know my method for measuring didn't work. That was so obvious it didn't occur to me that anyone would think I would continue with it. I was just mentioning WHY I did it. I have no intention of EVER doing it again. I plan on trying the different techniques mentioned and figure out what works best.

As to the beer, I'd like to get it a close to true as I can given the mistake of over cooling it. Plus, a small taste and going through a whole keg will be a very different experience. I can see a flavour that doesn't bother me in a taste bothering me after the third week of drinking it daily .

Is it too far from the FG? Should I continue until I'm closer? Now that I have the thief I might as well use it.

Thanks.

My bad - hopefully if you try the side of the carboy it will work better for you next time.

So you're at about 1.022 right now which is a bit high (http://www.bjcp.org/2008styles/style05.php). Probably not a bad idea to see if you can get it a little lower by leaving it ~18C for a while. If it doesn't doesn't go lower, you might be able to finish it off with a repitch of actively fermenting yeast (could be ale yeast, doesn't matter too much at this stage) or just go with it.

Won't the gravity change during the final month or so of lagering? How close to the FG should I be before the lagering. From what you mentioned I get the idea I should be at the FG before lagering, but I thought it was supposed to be only 80% done for the rest period and then how close before cooling it down?

Thanks.

[mr x]

Beer should be finished before lagering.

Sent from my Nexus S

[Jayme]

I've seen it drop maybe a point or two during lagering, but yes it should be at FG or very, very close before you cool it down. The yeast is still 'active' but think of it as the party is over, they're just cleaning up the mess before going to bed.