Fermenting a lager for the 1st time

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kproudfoot

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Going to lager for the 1st time.
I have a fridge I will be using along with a inkbird temp controller and a pad to heat with. My question is my fermentor doesn’t have a thermowell for the temp probe. I would assume the air temp is different than the temp of wort. Any ideas how to handle this?
 
Your 100% right about the temperature difference between ambient an actual wort temperature, especially during active fermentation.
Ive always taped the temperature probe to the outside of the fermenter, insulated with two pieces of butchered beer cooler, Always served me well, including my first lager only recently.
Picture attached for reference, skeezerpleezer's Zombie Dust Clone happily fermenting 24 hours after pitching.
IMG_0816.JPG
 
I just tape the probe to the outside and cover it with a split piece of foam pipe insulation. Lager fermentations don't get to vigorous around 50* anyway.
 
Ok thanks. I am planning on using my spiedel so it’s pretty thick. Wasn’t sure if that would matter. If I had more time I’d order a thermowell
 
A thermowell would also be an advantage when you cold crash your beer; by monitoring the center of the batch the fridge will run constantly bringing the beer temp down steadily in a shorter time than using an ouside probe which will cause the fridge to kick off and on every few hours as the outer surface beer is being measured. The quicker you crash it, the more completely all the suspended particles and chill-haze causing proteins will be dropped. It's worth ordering one now and switch to using that sometime during primary fermentation.
 
One good thing is lager fermentations don’t create that much heat so the difference between ambient and liquid isn’t generally that great.
 
The air temp in the fridge is nowhere close to what the wort is doing. I use a fermentasaurus inside a fridge with a Johnson temp controller, pretty much the same setup you have. I installed a weldless thermowell from morebeer into the fermenter and put the probe inside that. Before I put the probe in, I glop it up with keg lube for good thermal contact. It really works well.
 
I ferment IPA and pale ales with lager yeast, 34/70, at ale temps and they are spectacular if I may say so myself. I have the means to ferment at low temps but why bother if I don’t have to? I think any lager yeast will do fine in the mid 60s.
 
I ferment IPA and pale ales with lager yeast, 34/70, at ale temps and they are spectacular if I may say so myself. I have the means to ferment at low temps but why bother if I don’t have to? I think any lager yeast will do fine in the mid 60s.

The yeast may 'do fine' but the beer definitely won't taste the same as when fermented cold.
 
Nothing wrong with using a lager yeast at ale temps. It's not a lager, but it is beer. It's not going to taste the same, but it may be quite palatable. If you really like the taste, hell, use bread yeast fermented at 90F. You won't make a dead nuts on Pilsner Urquell clone fermenting at 65F. And fermenting a Saison at 58F is not going to resemble a Saison either. Thats reality.

I'm a firm believer that no matter what is used or how it's made, someone somewhere will think its wonderful. And if you give it a cool name and put skulls or dragons on the label, it will sell like hotcakes :)
 
i would challenge anyone here to tell the difference between a lager fermented at 65 and one fermented a 50 or 45. it's been tested before, even with beer judges (for whatever that's worth) and they have not been able to reliably tell the beers apart. i'm not saying that anyone should change their practices, i'm saying a lager at 65 is as clean as a lager at any temperature below 65. not passable or ok, crisp and clean. the way to know for yourself is to try it.
 
I will take that challenge as I'll bet will many others who have experience with cold ferments. There is a large and noticeable difference between a lager fermented at 45-48 and those done above 55. If there isn't any in yours then I assume your doing something wrong or can't taste the difference.
If there wasn't a different then all macro lagers would be fermented warm.
 
I will take that challenge as I'll bet will many others who have experience with cold ferments. There is a large and noticeable difference between a lager fermented at 45-48 and those done above 55. If there isn't any in yours then I assume your doing something wrong or can't taste the difference.
If there wasn't a different then all macro lagers would be fermented warm.

I am a sample size of one so i'm not only relying on my experiences, many other brewers have fermented lagers at ale temps with excellent results. i just looked at a package of 34/70 and the high end of the temp range is 71, i never noticed that before. it does have an "ideal" temp too which ranges up to 59. again, i'm not trying to tell people to do this, i'm just saying that it can be done and it is not a compromise.
 
How about y'all stay on topic for the OP.

34/70 isn't a true lager strain and warm fermented lager is not the same as cold fermented.

OP do a lager properly first then change your practice if you want to see the difference. Tape the temp probe to outside of fermenter and insulate with foam or neoprene. I get basically the same temp on my internal tilt hydrometer as the temp probe on fermenter.
 
How about y'all stay on topic for the OP.

34/70 isn't a true lager strain and warm fermented lager is not the same as cold fermented.

OP do a lager properly first then change your practice if you want to see the difference. Tape the temp probe to outside of fermenter and insulate with foam or neoprene. I get basically the same temp on my internal tilt hydrometer as the temp probe on fermenter.


Hold up, I'm staying off topic... "34/70 is not a true lager strain"? Where do you get that? Feel free to PM me if you are concerned about polluting the air waves in this forum.
 
How about y'all stay on topic for the OP.

34/70 isn't a true lager strain and warm fermented lager is not the same as cold fermented.

OP do a lager properly first then change your practice if you want to see the difference. Tape the temp probe to outside of fermenter and insulate with foam or neoprene. I get basically the same temp on my internal tilt hydrometer as the temp probe on fermenter.

This.

I agree with this 100%. Depending on what material your fermentation vessel is made of, the outside can be pretty close to actual wort temp. I did an experiment using two probes fermenting with a glass carboy. Probe #1 directly in the wort was less than 1°F different from probe #2 which was insulated (foam blocks work great) and taped to the outside.

Now that I'm fermenting in corny kegs (metal) I imagine it's even less.
 
There are so many process variables that come into play other than just temp.

When I’m making lagers I’m not going for crisp and clean. I’m going for depth and malt complexity. Attributes you can’t get when a fermentation is above a certain temp at any time during fermentation.
 
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...Depending on what material your fermentation vessel is made of, the outside can be pretty close to actual wort temp. I did an experiment using two probes fermenting with a glass carboy. Probe #1 directly in the wort was less than 1°F different from probe #2 which was insulated (foam blocks work great) and taped to the outside.

At a constant fermentation temp, of course there would be practically zero difference. That is until you ramp up or down, or cold crash your beer. An internal probe will result in the beer cooling down steadily and rapidly to the desired temperature whereas an external probe will result in the refrigerator cycling on and off and a slower crash. I use an extremely efficient crash setup; a monster energy cylindrical refrigerated merchandiser that holds one 7 gallon fermonster with less than 2" dead space around the sides, 3" underneath and zero clearance on top. Using an insulated external probe takes several hours longer to crash from 62f d.rest down to 32f than it does with a thermowell. And the benefits also include cooling wort to pitching temps with as little lag time as possible. I chill in the kettle down to mid-70s, then bring it down to 55 before pitching. I waffled for a long time about bothering with an internal probe because I was brewing mostly ales and it wasn't that useful. Now that I brew lagers too I wouldn't be without a thermowell.
 
At a constant fermentation temp, of course there would be practically zero difference. That is until you ramp up or down, or cold crash your beer. An internal probe will result in the beer cooling down steadily and rapidly to the desired temperature whereas an external probe will result in the refrigerator cycling on and off and a slower crash. I use an extremely efficient crash setup; a monster energy cylindrical refrigerated merchandiser that holds one 7 gallon fermonster with less than 2" dead space around the sides, 3" underneath and zero clearance on top. Using an insulated external probe takes several hours longer to crash from 62f d.rest down to 32f than it does with a thermowell. And the benefits also include cooling wort to pitching temps with as little lag time as possible. I chill in the kettle down to mid-70s, then bring it down to 55 before pitching. I waffled for a long time about bothering with an internal probe because I was brewing mostly ales and it wasn't that useful. Now that I brew lagers too I wouldn't be without a thermowell.

I thought we were just talking about fermentation temps and the often debated "magnitude of heat caused by fermentation". Perhaps I misunderstood.

That sounds like a great setup! I think I basically agree with everything you've said with regards to the speed of crashing and using a thermowell / immersed probe vs outside. But I would ask, do you over or undershoot? I found that a probe insulated to the vessel on the outside provides a much more favorable damped system response, albeit somewhat slower than your method. When I used the probe inside the wort, I noticed the system response was not ideal when ramping up or down. That is, it would way under or overshoot my target temp. I just assumed this was due to a fairly substantial temperature gradient in a glass carboy from the center to the outside and not the difference in dead chamber volume given the relatively large mass of wort vs air mass and their differences in specific heat capacity.
 
I thought we were just talking about fermentation temps and the often debated "magnitude of heat caused by fermentation". Perhaps I misunderstood.

That sounds like a great setup! I think I basically agree with everything you've said with regards to the speed of crashing and using a thermowell / immersed probe vs outside. But I would ask, do you over or undershoot? I found that a probe insulated to the vessel on the outside provides a much more favorable damped system response, albeit somewhat slower than your method. When I used the probe inside the wort, I noticed the system response was not ideal when ramping up or down. That is, it would way under or overshoot my target temp. I just assumed this was due to a fairly substantial temperature gradient in a glass carboy from the center to the outside and not the difference in dead chamber volume given the relatively large mass of wort vs air mass and their differences in specific heat capacity.
Never noticed any ice forming, but its entirely possible. IME, the overshoot is less consequential than the lag time. The overall time to reach stasis at any given target temperature is shorter.
 
I'm doing my first lager as well. Ideally, I would have one of those wireless probes, but I just use a sticker thermometer and a freezer with a temp controller ~50F. I'm sure the fermentation is closer to 52-54F. I pitched at about 70F.
 
I ferment IPA and pale ales with lager yeast, 34/70, at ale temps and they are spectacular if I may say so myself. I have the means to ferment at low temps but why bother if I don’t have to? I think any lager yeast will do fine in the mid 60s.
Look at Mangrove Jack's M54 Californian Lager yeast. It's a true lager yeast that ferments at ale temperatures.
 
to get back on topic....
you could add a thermowell if you find that you’re getting more ester production than desired. If you’re using a bucket, drill a hole for a stopper and get a stopper with a dual hole for a thermowell and airlock...
Those stoppers also work for carboys.
Conicals is another story...
ps - inkbird makes a 12” ntc probe that u have to wire in (not too hard i just havent done it yet for mine). i need to check if that probe is the same diameter as a standard thermowell.
 
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