Ambient or Fermentor temp?

brownbeard · Post by **brownbeard** » Mon Aug 31, 2009 7:31 pm

I have always tried to stay on the lower end of fermenting temps for all my beers. I make pretty clean beers. But sometimes, clean is not what you are looking for. Some of my belgians, for instance, come up a little lacking on that "belgianness". Know what I mean? In an effort to correct this, I decided to go with a higher temp on my belgian brew from yesterday. I am making sort of an imperial wit. Gravity around 1.06 and IBU's at 37. I used Wyeast 1214. Optimum temps are between 68 and 78 degrees F. I set my ambient temp in the brewing room to 77 degrees.

When I came home from work today the room was indeed 77*F. Wonderful, I thought. The beer was bubbling away happily. Things were going far too well. I needed to complicate the situation. So, I sanitized my digital thermometer, and checked the temp in the fermentor. 88*F

What the hell was I thinking? I never check fermentor temp. Why would I do something so dumb? Now I can't stop worrying about it. On the upside, the stuff licked off the thermometer already tastes pretty good. So, I killed the space heater in the room. The ambient temp is down to 74. Fermentation has slowed a bit, but still moving pretty fast. It was rocking before.

What are your experiences with high fermentor temps? I know I was recently reading an article somewhere about high temp fermenting of belgians. Of course I can't find it now.

Lower Case T · Post by **Lower Case T** » Tue Sep 01, 2009 7:20 am

I think that will be a tasty beer. Your only concern would be how fast it got up to that temp. It seems that if you let it rise too quickly the alcohol will be very prevalent in the taste. I don't think the high temp is anything to worry about as long as you let it get there reasonably slowly. I think I read 4-5 degrees a day over a seven day period for a duval clone I tried. Its probably in Jamil's book.

All is well. Or if not, just give it to Big T, he'll drink it :) (and by Big T, I mean me)

On Mon, Aug 31, 2009 at 8:31 PM, brownbeard <brew-tech@crbeernuts.org (brew-tech@crbeernuts.org)> wrote:

I have always tried to stay on the lower end of fermenting temps for all my beers. I make pretty clean beers. But sometimes, clean is not what you are looking for. Some of my belgians, for instance, come up a little lacking on that "belgianness". Know what I mean? In an effort to correct this, I decided to go with a higher temp on my belgian brew from yesterday. I am making sort of an imperial wit. Gravity around 1.06 and IBU's at 37. I used Wyeast 1214. Optimum temps are between 68 and 78 degrees F. I set my ambient temp in the brewing room to 77 degrees.

When I came home from work today the room was indeed 77*F. Wonderful, I thought. The beer was bubbling away happily. Things were going far too well. I needed to complicate the situation. So, I sanitized my digital thermometer, and checked the temp in the fermentor. 88*F

What the hell was I thinking? I never check fermentor temp. Why would I do something so dumb? Now I can't stop worrying about it. On the upside, the stuff licked off the thermometer already tastes pretty good. So, I killed the space heater in the room. The ambient temp is down to 74. Fermentation has slowed a bit, but still moving pretty fast. It was rocking before.

What are your experiences with high fermentor temps? I know I was recently reading an article somewhere about high temp fermenting of belgians. Of course I can't find it now.

--
Prost!
Travis Scheidecker
Head Brewer
Third Base Brewery
500 Blairs Ferry Rd NE
Cedar Rapids, IA 52402
Tel. 319-378-9090 Fax: 319-378-9697
www.thirdbasebrewery.com

Post generated using Mail2Forum (http://www.mail2forum.com)

Derek · Post by **Derek** » Tue Sep 01, 2009 8:19 am

Stan Hieronymus, author of Brew Like a Monk, suggests starting fermentation at a lower temperature, and then increasing the fermentation temp toward the end of fermentation (last couple days).

Of course it's the temperature in the fermenter that counts, but beer is very forgiving...it'll probably be fine. Probably. It's not like you did the entire ferment that high.

brownbeard · Post by **brownbeard** » Tue Sep 01, 2009 8:52 am

I pitched a pretty good starter, and aerated for >30 minutes. So, it was fermenting within an hour of pitching yeast. Yesterday morning (~12 hours after pitching) it was not that warm, and fermenting pretty smoothly. It was not until later in the day that the temps ramped up. As soon as I discovered it, I lowered temps in the brewing room to 74. Just a 3 degree drop in ambient temp made a drastic change in the speed of fermentation. Once that slowed, the temp in the fermentor dropped substantially. My guess is that it would have been at those high temps for about 3-4 hours.

By this morning, the fermentation had slowed to about 1 bubble every 2 seconds.

Recipe was simple.
6 lb. 2-row
4 lb. white wheat
1 lb. flaked oats
2 oz. Saaz 3%AA for 60 min
2 oz. Saaz 3%AA for 30 min
2 oz. tangelo zest 10 min
.5 oz. ground coriander 10 min (could not find whole locally)
1 oz. Saaz 3%AA flameout
Wyeast 1214

My efficiency was 74% OG was 1.058 IBU should be ~37

Schlenkerla · Post by **Schlenkerla** » Tue Sep 01, 2009 9:24 am

Your beer will be fine. Accidents make some of the best beers!!!

I made a French Saison and the exact same thing happened to me. Its prolly one of my best beers too. Made this beer last summer. Still have a 3/4 case of bombers left. If I get to one of your meetings you might get a sample.

BTW - I entered it in for Pro/AM at The Court Ave Brewery.... They said that mine was by far better than any other entries. Unfortunately, they decided not to go into the running this year.

brownbeard · Post by **brownbeard** » Tue Sep 01, 2009 9:34 am

I'm not really too worried that the beer will be ruined. I'm mostly interested in whether others take fermentor readings, or trust ambient temperature.

DrPaulsen · Post by **DrPaulsen** » Tue Sep 01, 2009 9:38 am

brownbeard wrote:I pitched a pretty good starter, and aerated for >30 minutes. So, it was fermenting within an hour of pitching yeast. Yesterday morning (~12 hours after pitching) it was not that warm, and fermenting pretty smoothly.

Based on my experiences, I'd say your fine.

I've been using a 2-stage temp controller system (i.e. fridge and wrap heater) for a couple of years now. After using the system for five or six batches, I noticed that most of my beers were coming out with a lot of hot alcohols and esters. I decided it might be worth calibrating the thermocouples -- turns out they were off by about 6 degrees. So, while I thought I was fermenting at 68F, it was actually closer to 74F. Since I recalibrated my TCs, my beers have been much, much cleaner.

That being said, I don't think you have anything to worry about. Since re-calibrating my system, I typically start fermentation at 64-68F for ales. Once high krausen has been reached, I ratchet up the temp a few degrees every day or so until fermentation is complete. I will often finish the last few days of fermentation around 75-77F, with no discernable impact on flavor.

In summary, then, I'd say that as long as the first 12 or so hours of fermentation were under control, you're fine. Once the yeast stop reproducing and start getting down to business, it seems like the temperature range matters much less.

brownbeard wrote:Recipe was simple.
6 lb. 2-row
4 lb. white wheat
1 lb. flaked oats
2 oz. Saaz 3%AA for 60 min
2 oz. Saaz 3%AA for 30 min
2 oz. tangelo zest 10 min
.5 oz. ground coriander 10 min (could not find whole locally)
1 oz. Saaz 3%AA flameout
Wyeast 1214

FWIW, you can find whole coriander at the Mexican grocery behind La Salsita on 1st Ave.

DrPaulsen · Post by **DrPaulsen** » Tue Sep 01, 2009 9:42 am

brownbeard wrote:I'm not really too worried that the beer will be ruined. I'm mostly interested in whether others take fermentor readings, or trust ambient temperature.

Fermenter.

In the winter, I use a thermowell. In the summer, I just read fermometer strips on the outside of the carboys.

Schlenkerla · Post by **Schlenkerla** » Tue Sep 01, 2009 9:48 am

I normally rely on ambient temps, but I have tape thermometers on all of my fermentors. I normally have my beers cranking away in the basement where its anywhere from 58-68F.

Not to over state the obvious, I bet the internal temp of the beer is hottest in the center and lower on the outside. How many people have beer brewing at ~68F ambient and the internal at 73-78F? Probably alot of us.

Knowing too much can make you needlessly worry!!!

What would be interesting the temp difference on a lagering beer.

Were you thinking the heater was up that high during the heating cycle?

DrPaulsen · Post by **DrPaulsen** » Tue Sep 01, 2009 9:51 am

Schlenkerla wrote:Not to over state the obvious, I bet the internal temp of the beer is hottest in the center and lower on the outside. How many people have beer brewing at ~68F ambient and the internal at 73-78F? Probably alot of us.

In my experience, the interior of an active fermetner is typically not more than 1F warmer than the exterior. There are a lot of convection currents rolling around inside of an active fermentation that dissipate thermal gradients.

Schlenkerla · Post by **Schlenkerla** » Tue Sep 01, 2009 9:58 am

DrPaulsen wrote:
Schlenkerla wrote:Not to over state the obvious, I bet the internal temp of the beer is hottest in the center and lower on the outside. How many people have beer brewing at ~68F ambient and the internal at 73-78F? Probably alot of us.
In my experience, the interior of an active fermetner is typically not more than 1F warmer than the exterior. There are a lot of convection currents rolling around inside of an active fermentation that dissipate thermal gradients.

That's probably right! To me, its not something I'd be too worried about though.

Your point was interesting about the growth phase being hotter than the rest of the yeast metabolism cycle.

Great! - Now I will be thinking about this on my next batch!

Matt F · Post by **Matt F** » Tue Sep 01, 2009 4:38 pm

What is a fermentation temperature? Just kidding. I also like to start mine as low as I can be patient for when chilling and then let it ramp up. I got a fridge from DrPaulsen I have not used yet but plan to use it to keep the ramp up slower. Mine tend to heat up fairly quickly. I have been using a water bath to help slow things down a bit with some ice packs. I usually just go by the temp on the sticker on the side of the carboy.

Brownbeard, I think you beer will just not work. Instead of dumping it out you can bring it to my house and dump it down my throat.

Seriously though I bet it will be great.

BaronVonHawkeye · Post by **BaronVonHawkeye** » Wed Sep 02, 2009 8:18 pm

On the discussion of the fermentation moving around due to internal convection, isn't it possible that a glass fermenter could provide enough insulation to get it that warm? If you had the room at a firm 77F, there may not enough temperature gradient between the fermenter and the room to keep the temperature of the beer lower. Add in the possibility of stagnant air in the room, there is a possibility of internal fermentation temperature rise up to 11 degrees.

Cedar Rapids Brewing Society