Ferment temps - facts vs. myths please..

[springer]

The probe should be taped/attached directly to the carboy, then insulate the outer part.

For those that keep a glass carboy in a water bath, in that case you can just measure the water bath temp and you'll be close enough. Within a degree or two ime. The water is so much of a better conductor of heat than air is, it is able to keep the carboy contents very close to the water bath temp. But in air, not so much. It may also work with Better Bottles but that plastic insulates better than glass and I don't have any Better Bottles so I haven't tried it.

I have found no real difference between the glass or BB in a water bath. Its my main way of temp control other than doing lagers which go into the fridge/chest freezer.

 

[Brewing Clamper]

(bobbyfromNJ)

Not trying to hijack, I'll get off as soon as I get this answer but... is that an upright freezer with coil racks bent back? I might be able to get a free upright but I wasn't going to because the racks are not removable. How hard was it to bend them without breaking? Thanks... now back to your regularly scheduled thread.

 

[Bobby_M]

I was only $20 into this freezer so I didn't care what might have happened. It turned out to be easy and this thing is over 20 years old too.

 

[k1200rsvt]

I must say, this has been an interesting thread to read through. I've been back to brewing for about 9 months now (brewed a couple of batches 10+ years ago) and while I have tried to keep temperature control by keeping the ambient consistent I hadn't really realized that fermentation could create that much additional heat.

A couple of questions that come to mind...Has anyone compared a fermometer to the thermometer method described above? I have always assumed that they weren't perfect but were "close enough" but now I am curious. Also in keeping temperature control, how much variance is acceptable in an ideal situation? Thanks.

 

[RegionalChaos]

Sooooo.... when I build my ferm chamber, I should plan on having my controller temp prob be able to be relocated to the side of any ferm vessel in the chamber, and then just set it on the one that is the most active, or hottest. Sounds like a good plan. Thanks for the info guys.

 

[TheCookieMonster]

That's a 10F delta between dormant beer and really actively fermenting beer. Now, most beers don't ferment this exothermic because they don't start out 1.118 OG and usually don't get 900 billion yeast cells at once.

However, beer will always ferment at least a couple degrees above ambient. I would never ferment anything other than maybe a Saison at over 72F ambient.
(bobbyfromNJ)

Thanks!!

BobbyfromNJ once again comes through with the goods. Since I'm brewing mostly around 5% ABV, there shouldn't be a large differential which is great.

So today I went and got an air conditioner that goes down to 61F and am building a fermentation room downstairs.

Now I have to battle through how I should insulate the room as people are saying different things. I also bottle so wanted the room for bottle conditioning.

 

[TheCookieMonster]

I must say, this has been an interesting thread to read through. I've been back to brewing for about 9 months now (brewed a couple of batches 10+ years ago) and while I have tried to keep temperature control by keeping the ambient consistent I hadn't really realized that fermentation could create that much additional heat.

A couple of questions that come to mind...Has anyone compared a fermometer to the thermometer method described above? I have always assumed that they weren't perfect but were "close enough" but now I am curious. Also in keeping temperature control, how much variance is acceptable in an ideal situation? Thanks.

I hear ya.. I've fallen victim to a lot of 'wife tales' in brewing and don't want to waste more time and money again.

Honestly I've never seen my sticker reach 5-10 degree's over ambient. Jamil says that the stickers are accurate (as bobby clearly demonstrated). I've never seen mine reach 5-10 degrees over. Mine have been pretty much room temp.. maybe 1 degree higher. But then again I've been brewing 4% ABV of poor yeast and wort so who knows.

I think Bobby answered everything clearly and I think most honestly don't know the real answers.

If you seriously don't know what makes a British import better than a local craft.. well then.. I think you have a bit to learn with brewing.

Same with your temps on the sticker. Lets be honest.. most here don't know they're temps.

I feel Jamil from the Brewing Network knows his stuff. BobbyFromNJ also knows his stuff.

I've gathered that I have to run just a few degree below ferment tamps. So 61-64 or so ambient should be perfect (according to what Jamil likes for his ferment temps). Even then Jamil doesn't make it a large issue.. as long as it's in the range of 64-68. His main concern is sanitation and the yeast cell count.

 

[bob1852]

Someone who brews 250 batches will not tell me his fermentation temp on his stickers or how much I should be expecting the temps to rise.

just for the record, Yooper is a female....

 

[jppostKW]

I hear ya.. I've fallen victim to a lot of 'wife tales' in brewing and don't want to waste more time and money again.

Honestly I've never seen my sticker reach 5-10 degree's over ambient. Jamil says that the stickers are accurate (as bobby clearly demonstrated). I've never seen mine reach 5-10 degrees over. Mine have been pretty much room temp.. maybe 1 degree higher. But then again I've been brewing 4% ABV of poor yeast and wort so who knows.

I think Bobby answered everything clearly and I think most honestly don't know the real answers.

If you seriously don't know what makes a British import better than a local craft.. well then.. I think you have a bit to learn with brewing.

Same with your temps on the sticker. Lets be honest.. most here don't know they're temps.

I feel Jamil from the Brewing Network knows his stuff. BobbyFromNJ also knows his stuff.

I've gathered that I have to run just a few degree below ferment tamps. So 61-64 or so ambient should be perfect (according to what Jamil likes for his ferment temps). Even then Jamil doesn't make it a large issue.. as long as it's in the range of 64-68. His main concern is sanitation and the yeast cell count.

You have heard from who knows how many thousands of gallons of experience and still say we dont know whats going on ferm wise or how to make a good beer.
I take a data log of all my ferms with time, chamber temp, and wort temp 10 samples an hour and load them onto spread sheets to compare. You are basing all of your info off one brewer Jamil is a very knowledgeable source of info but his methods work for him and his setup Papazain and Palmer might have completely different ideas. You have to find out your needs for temp control and base your build on that.

I am going to meet Jamil in June I will see how he controls temp and whether or not he relys on his stick on thermometer

 

[Yooper]

Right now, my laundry room is 57 degrees. My cream ale (using S04 yeast) is at 63 degrees. That's perfect for me.

Someone who brews 250 batches will not tell me his fermentation temp on his stickers or how much I should be expecting the temps to rise.

How was that too far above your level of understanding? It's in plain English, and the longest word has two syllables.

This isn't trolling.

Yeah, it is. You've insulted me in other threads, and been sarcastic and demeaning in this one. We've let it continue because there is good information in this thread, for those who have enough sense to read.

I will agree that Bobby_M is incredibly helpful with much to offer. I always appreciate his input and what he has to say.

 

[Bobby_M]

As much as I appreciate the flattery, it's important to realize that this community here is made up of at least hundreds of people I have a lot of respect for. I owe at least half of everything I know about brewing to the people who have come before me and have offered to share their experiences. No one is ever right 100% of the time but it's the overall community effort that makes us better brewers.

My advice, if it seems like you're getting a suspect answer, just let it slide and pay attention to the overall vibe.

 

[Netflyer]

Wow I guess there's a whole bunch of people brewing wrong.

I can say for sure without a doubt that my sticker has never, ever read not even more than 1 degree more than ambient temps. That's the only thing I can say for certain.

What is the OG of those beers that only rise 1 degree above ambient? How much and what type of yeast(s) did you use on those beers? Give examples please.

My 1.040-1.050 rise 1-3 degrees over ambient, between 1.050-1.060 4 or so degrees and anything larger is 5+ degrees. It's more important to note the temp and make sure it doesn't exceed the yeast's rated upper or lower end then to worry about some general rule, because frankly a general rule does not apply.

 

[remilard]

Honestly I've never seen my sticker reach 5-10 degree's over ambient. Jamil says that the stickers are accurate (as bobby clearly demonstrated).

You must be a horrible communicator. I have been understanding you to say, and I think others have as well, that the sticker will read the same temperature as ambient. Bobby demonstrated something completely different visually. Now, if you agree with what Bobby said then you agree with all of the rest of us and somebody (either you or the other 20 of us) did a bad job communicating.

 

[Yooper]

What is the OG of those beers that only rise 1 degree above ambient? How much and what type of yeast(s) did you use on those beers? Give examples please.

My 1.040-1.050 rise 1-3 degrees over ambient, between 1.050-1.060 4 or so degrees and anything larger is 5+ degrees. It's more important to note the temp and make sure it doesn't exceed the yeast's rated upper or lower end then to worry about some general rule, because frankly a general rule does not apply.

Here's another wrinkle- fermenting cool tends to be a slower and steady fermentation. While fermenting "hot" tends to rev the yeast up even more and cause more vigorous activity. So, a cool temperature ferment might only rise 2,3,4 or 5 degrees above ambient. But, a warm pitch (some homebrewers pitch at 70-80 degrees, in a rush), and a warm ambient temperature will cause the yeast to go gangbusters, putting out even more heat, so it's a vicious cycle. Hotter fermentations will tend to get hotter and hotter, even 10-12 degrees above ambient, since the yeast are going wild and producing even more heat.

Like the tortoise and the hare, in a way. Slow and steady wins the race (to better beer), rather than a quick explosion of activity.

 

[DeafSmith]

I've just now read through this thread, and I've got a question. If you tape the temp. probe to the carboy and then insulate it, it seems to me that the low point of the ambient temperature swings will be very much lower than the beer temp. due to the thermal mass of the liquid in the carboy. If you're using a chest freezer rather than a refrigerator, I could imagine the ambient dropping below freezing before the probe registered enough of a drop to turn the freezer off. Could this even freeze the liquid in the airlock? Should a different technique for mounting the probe be used in a freezer vs. a fridge?

 

[jppostKW]

I've just now read through this thread, and I've got a question. If you tape the temp. probe to the carboy and then insulate it, it seems to me that the low point of the ambient temperature swings will be very much lower than the beer temp. due to the thermal mass of the liquid in the carboy. If you're using a chest freezer rather than a refrigerator, I could imagine the ambient dropping below freezing before the probe registered enough of a drop to turn the freezer off. Could this even freeze the liquid in the airlock? Should a different technique for mounting the probe be used in a freezer vs. a fridge?

I use a Son of a ferm chiller style chamber so i cant answer on the freezer part but a simple solution is to use cheap vodka in the airlock which is what i use.

 

[remilard]

I've just now read through this thread, and I've got a question. If you tape the temp. probe to the carboy and then insulate it, it seems to me that the low point of the ambient temperature swings will be very much lower than the beer temp. due to the thermal mass of the liquid in the carboy. If you're using a chest freezer rather than a refrigerator, I could imagine the ambient dropping below freezing before the probe registered enough of a drop to turn the freezer off. Could this even freeze the liquid in the airlock? Should a different technique for mounting the probe be used in a freezer vs. a fridge?

I use freezers and if you are trying to keep the beer at, say, 68 with a 1 degree differential this is not a problem. If you crash chill to 30 from 68, yes the airlock will freeze solid (which isn't much of a problem).

 

[TheCookieMonster]

Ok I found where Jamil himself talks about this:

http://thebrewingnetwork.com/shows/533

Download the MP3 and go to 56 minutes where he addresses this issue of the stick on thermometers being 0.5 degrees accurate.

Ouch.. I just heard Jamil saying that he doesn't promote secondary fermenation. he said that it's old school. He's also saying that people should bottle carbonate 50-60 degrees. It will take longer, but the bottle will keep for years. He said you have to store them in near freezing temps. He said that he's entered beers in competitions this way.

 

[TheCookieMonster]

My 1.040-1.050 rise 1-3 degrees over ambient, between 1.050-1.060 4 or so degrees and anything larger is 5+ degrees.

Thanks for that advice!

I got an air conditioner today for $117 that will sit down to 61. I hope this space works out. I'm trying to figure out the insulation type to use for the best results that will keep in the cool. The air conditioner has a built in thermostat. If White Labs says 68, then hopefully I can get the area at 61 for the English Ale yeast. The temp will not go below 61 on the air conditioner.

The WLP001 will produce a fairly dry, clean bear. You can use it in the late 50's or mid 70's. This one guy says that it's all just Safale S-05.

WLP001 California Ale Yeast
This yeast is famous for its clean flavors, balance and ability to be used in almost any style ale. It accentuates the hop flavors and is extremely versatile.
Attenuation: 73-80%
Flocculation: Medium
Optimum Fermentation Temperature: 68-73°F
Alcohol Tolerance: High

WLP005 British Ale Yeast
This yeast is a little more attenuative than WLP002. Like most English strains, this yeast produces malty beers. Excellent for all English style ales including bitter, pale ale, porter, and brown ale.
Attenuation: 67-74%
Flocculation: High
Optimum Fermentation Temperature: 65-70°F
(18-21°C)
Alcohol Tolerance: Medium

 

[jppostKW]

Ok I found where Jamil himself talks about this:

http://thebrewingnetwork.com/shows/533

Download the MP3 and go to 56 minutes where he addresses this issue of the stick on thermometers being 0.5 degrees accurate.

Ouch.. I just heard Jamil saying that he doesn't promote secondary fermenation. he said that it's old school. He's also saying that people should bottle carbonate 50-60 degrees. It will take longer, but the bottle will keep for years. He said you have to store them in near freezing temps. He said that he's entered beers in competitions this way.

Fail.... no where in the 12 minutes preceding or following your minute mark are stick on ferms mentioned. his discussion of .5 degree accuracy is talking about difference between the internal wort temp and temp measured with the johnson temp controller PROBE he uses to control his ferm temps.
he than goes on to talk about bubble wrap over probe just taping it on or sticking between 2 carboys for 10 gal batches. All things he mentions have been mentioned here previously

 

[ChshreCat]

I did listen to the podcast where he talks about accuracy of stick on fermometers, but it's more of an aside than anything. Not a serious subject. Someone mentions stick on fermometers and he says he thinks they're fairly accurate and then they go back on subject. I'd rather trust a real thermometer and use the stick on ones as just a general guide. I can't see them as being .5 degrees accurate because I can't really tell if the 64 is more colored or the 68.

 

[Yambor44]

HAHAHA! Missed that!




Understandable. But wouldn't it, in turn, protect and insulate the probe from the temps inside the vessel?



I agree. This is why I set the controller at 65 "ambient" (temp inside the freezer) and the 2 degree differential swings the ambient temp between 63 at the lowest to 67 at the highest. With that being said, I usually cool my beers to around 60-65 degrees before pitching my yeast. I do this by IC or CFC. I use dry yeast, Safale US-05 and pitch one packet per 5.5 gallons of wort. I do not re-hydrate. I then place it in the aforementioned environment (deep freezer). It almost always takes at least 18-24 hours before I notice bubbles in the airlock. My fermentation is normally very mild and steady for about 3-4 days then it tappers off. Most of my beers are around 1.050 to 1.060 OG. I have never checked the temp on the side of the vessel during fermentation.

I really want to understand this insulated probe thing if that will help me to control a little better. The next batch I brew (hopefully this weekend if my stand is ready) I will do a little experiment. I will leave the controller probe hanging in the "ambient" and the digital thermometer also. Both 12 INCHES (LOL) from the bottom. Then I will take a separate probe and attach it to the side of the fermenting vessel with no insulation. Then I will take yet another probe and insulate it in bubble warp and attach it to the other side of the fermenting vessel. Then I will monitor and record the temps daily for the first 7 days. That should tell me something.

Here's another wrinkle- fermenting cool tends to be a slower and steady fermentation. While fermenting "hot" tends to rev the yeast up even more and cause more vigorous activity. So, a cool temperature ferment might only rise 2,3,4 or 5 degrees above ambient. But, a warm pitch (some homebrewers pitch at 70-80 degrees, in a rush), and a warm ambient temperature will cause the yeast to go gangbusters, putting out even more heat, so it's a vicious cycle. Hotter fermentations will tend to get hotter and hotter, even 10-12 degrees above ambient, since the yeast are going wild and producing even more heat.

Like the tortoise and the hare, in a way. Slow and steady wins the race (to better beer), rather than a quick explosion of activity.

Good to know. I've often wondered about my lack of "vigorous" fermentation. I do keep my environment as steady as possible. I feel better now!

 

[Bobby_M]

I've just now read through this thread, and I've got a question. If you tape the temp. probe to the carboy and then insulate it, it seems to me that the low point of the ambient temperature swings will be very much lower than the beer temp. due to the thermal mass of the liquid in the carboy. If you're using a chest freezer rather than a refrigerator, I could imagine the ambient dropping below freezing before the probe registered enough of a drop to turn the freezer off. Could this even freeze the liquid in the airlock? Should a different technique for mounting the probe be used in a freezer vs. a fridge?

That's actually a great question, although it has been discussed before. This technique is a compromise. The problem you describe happens badly if you put the probe down into a thermowell in the center of the fermenter. The wort acts a really big temp buffer and icicles would be hanging off the carboy before the probe reacted.

Taping the probe to the fermenter on the outside with no insulation is slightly off on the other end of the spectrum. It's being slightly buffered by the wort, but still exposed to the ambient enough to be too touchy, potentially cycling the compressor on if you open the door for more than 30 seconds.

That small bit of insulation balances this out just enough. The cooling cycle however doesn't get too out of control before the probe senses it.

 

[remilard]

I did listen to the podcast where he talks about accuracy of stick on fermometers, but it's more of an aside than anything. Not a serious subject. Someone mentions stick on fermometers and he says he thinks they're fairly accurate and then they go back on subject. I'd rather trust a real thermometer and use the stick on ones as just a general guide. I can't see them as being .5 degrees accurate because I can't really tell if the 64 is more colored or the 68.

Exactly, even if they were perfectly accurate they don't offer .5 degree resolution, so it is impossible to confirm that they are that accurate or read them with that level of accuracy.

 

[forcera]

Exactly, even if they were perfectly accurate they don't offer .5 degree resolution, so it is impossible to confirm that they are that accurate or read them with that level of accuracy.

This is the temp strip on the barleywine:

This is the temp strip on the Amber that is not fermenting.

Like remilard said, I don’t see a .5 degree graduation on these or ANY stick on thermometer that I have ever seen. Without that it’s going to REALLY hard to say they are accurate to within .5 degrees.

 

[pjj2ba]

Wow, people are making a whole lot of assumptions here. Remember, when you assume things you make an ass out of u and me (a quote my major professor liked to say)

Do we all seriuosly think the we are all brewing under the same conditions, so all of our experiences and all of our finding are going to be exactly the same? It is perfectly reasonable for some folks to see little temp. delta and others see a big delta.

My house is heated by single point sources and convection currents move the heat around (no ducts, no plumbing for heating). If I close off a room it gets cold (or hot) pretty quickly. I can guarantee you that someone who ferments in a closet or small space is going to see a much bigger delta that someone who has the fermenter out in a open space where there is much greater convection movement of heat. The greater the diference between the carboy and ambient air, the faster the cooling, and the more air in the room the better. By analogy, we can all understand that if we have 200 gal. of cold water to chill our hot wort, it will do a much better job than if we only have 20 gal. of cold water. Air volume is no different for a fermenting carboy. More volume = more cooling and less delta.

The second part which is also overlooked is air movement. In the summer in my basement it hovers around 70 F. If I put my carboy in a tub of water and put a T-shirt over it to get some evaporative cooling, I can cool the fermenter 3-4 F. Now if I put a fan blowing on it, I can get it to cool 6-8 F. Better air movement = better cooling

When I built my fermentation chiller/lager chamber I quickly realized that I was getting pockets of warmer and colder air so I went out and bought a fan and wired it up so that when the compressor kicks on the fan also turns on. This has greatly improved air flow in the chiller and significantly narrowed the difference between "ambient" and fermentor temperatures. This helps to avoid both under and overchilling. I bought a tangential axis fan and installed it behind the chilling plate. I like this fan for its low profile upon installation. It doesn't stick out like typical salvaged computer fan would need to.

So now, since the majority of us are not fermenting in glycol jacketed conical fermenters, maybe we should give some more details when we post our findings, especially when it comes to fermentation temperatures. Like, I fermented it in a closet, or in a chiller. Then we the readers will have some ideas of how that might have impacted fermentation and can make beter and informed conclusions about the results

 

[TheCookieMonster]

Good to know. I've often wondered about my lack of "vigorous" fermentation. I do keep my environment as steady as possible. I feel better now!

That's not what Jamil says. He says that you should see a good amount of activity. (I wish I could reference the show.. there's just so many of them and so many hours of discussion).

How much yeast are you pitching? Jamil says 95% of people under pitch. You need 2L or half a gallon of yeast started per 5 gallons of wort.

If you are pitching your yeast direction in from bottle, keep in mind that 20% of it is likely dead and there simply isn't enough yeast cells to be handling ferment of 5 gallons.

When the Yeast leaves White Labs, it's 96% alive. When it gets shipped for 4 days total, it drops to 80%. Then depending on a bunch of other things it could be much less.

If you just want to put WyYeast in. You actually need 2 packets if you dont want a starter.

The first time you use your yeast it wont be it its best. The 3rd to 10th time you re-use your yeast it will be in it's zone and turn out amazing beer.

When you are making a starter, a stirplate will help to increase the cell count by a measurable amount.. Unfortunately, you'll need a 2L flask size which many people over look. Also dechlorinate the water when making a started.

Jamil said all of the above. I wish I could reference all this, but they came through more as bits and peices through various shows..

He did say though that you should definatly have active fermentation or you need to look at what you are doing if you aren't.

Oh and Jamil never uses dry yeast. He knows both owners of WyYeast and White Labs and says that they really take their yeast seriously and are all about quality beer in final products. He says that they really, really care in their products and such and that both products are excellent.

 

[TheCookieMonster]

Wow, people are making a whole lot of assumptions here. Remember, when you assume things you make an ass out of u and me (a quote my major professor liked to say)

Bingo.

I think most people don't really know their temps or aren't in touch with them.

John Palmer says the water and T-Shirt method works really well. But he says to put a fan on it. He also says that at terry cloth type material works better.

 

[Yambor44]

That's not what Jamil says. He says that you should see a good amount of activity. (I wish I could reference the show.. there's just so many of them and so many hours of discussion).

How much yeast are you pitching? Jamil says 95% of people under pitch. You need 2L or half a gallon of yeast started per 5 gallons of wort.

If you are pitching your yeast direction in from bottle, keep in mind that 20% of it is likely dead and there simply isn't enough yeast cells to be handling ferment of 5 gallons.

When the Yeast leaves White Labs, it's 96% alive. When it gets shipped for 4 days total, it drops to 80%. Then depending on a bunch of other things it could be much less.

If you just want to put WyYeast in. You actually need 2 packets if you dont want a starter.

The first time you use your yeast it wont be it its best. The 3rd to 10th time you re-use your yeast it will be in it's zone and turn out amazing beer.

When you are making a starter, a stirplate will help to increase the cell count by a measurable amount.. Unfortunately, you'll need a 2L flask size which many people over look. Also dechlorinate the water when making a started.

Jamil said all of the above. I wish I could reference all this, but they came through more as bits and peices through various shows..

He did say though that you should definatly have active fermentation or you need to look at what you are doing if you aren't.

Oh and Jamil never uses dry yeast. He knows both owners of WyYeast and White Labs and says that they really take their yeast seriously and are all about quality beer in final products. He says that they really, really care in their products and such and that both products are excellent.

As I stated in the quote you referenced, I pitch one packet (11.5 grams) per 5 gallons. I do get a good fermentation, just not vigorous to the ppoint I need a blow off tube. I would say my krueson (sp) averages 2-3 inches. It used to average 4 inches when I didn't have consistent temperature control storage. I also use dry yeast now for most of my beers. I only use others if I need a certain strain (such as Pac-Man). There are many debates regarding dry vs. liquid and starters and such so I won't debate that here. this works FOR ME.

As many others have stated, to each his own. I appreciate your input regarding Jamil. He is a wealth of knowledge and information and has many awards to prove it. However, he is not the end all in the beer making world. I have come to learn from and value many of the brewers input right here on this forum. So much so that I rarely, if ever anymore, go to other forums.

Thanks for starting this thread. Lots of good, valid information here from some "Jamil type" brewers. Once you've been around a little longer, you will find this out.

 

[Yambor44]

Bingo.

I think most people don't really know their temps or aren't in touch with them.

John Palmer says the water and T-Shirt method works really well. But he says to put a fan on it. He also says that at terry cloth type material works better.

Well, JAMIL said "this doesn't work well in humid areas such as Virginia".