Hot fermentation during high krausen

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whatisitgoodfor

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So last night I started a batch of honey brown. Ambient was sitting at 62, so I didn't bother loading my fermentation cabinet up with ice and just let it go.

This batch was on a cake left over from the last batch of brown I kegged last night and it started forming a krausen in about two hours. According to the fermometer on the carboy it was still sitting at 63-64 so I didn't think twice and went to bed.

Checked it again this morning and I had a blow out. Not worried about that, just worried about the fact that the digital thermometer taped to the carboy showed it at 88 degrees, 20 degrees above the new ambient (it warmed up during the night to 68, gotta love Texas.)

So the question I have is how much damage can I expect from WLP005 fermenting at almost 20 degrees too warm for 10ish hours?

\RNWADAHB while pondering the possibility of a banana nut brown instead of a honey brown.
 
Well, only time will tell I guess. Smell the airlock. Also, you said you used a fermometer when you pitched, then a digital taped to the side to get your 88F reading.

Is the digital waterproof? Did it happen to get wet during the blowoff? that could render a "non-waterproof" thermometer useless and give you all kinds of whacky readings. 20 degrees seems like a big delta between ambient and fermenter...
 
The digital thermometer isn't waterproof, but it does have plenty of electrical tape around the leads, and was taped under a 4x folded paper towel, but it may have gotten wet. I honestly didn't pay much attention to the carboy beyond cleaning the neck enough to get a good seal on the airlock again before leaving for work.

About the only reason I think 20 degrees is even possible is because it was closed up in a fermentation cabinet so there wasn't much opportunity for the cold air outside to circulate into it. I have no clue what the air temp inside the cabinet was before I opened it up.
 
Can you move it to another (cooler) spot and see if you get a change in temperature read? I'd have to agree that a 20 degree delta is pretty significant. How warm is it to the touch? If it is really 88 degrees, you will want it to cool it down quickly or risk having very fruity beer. I'm not sure if you like that flavor, but I had to dump a whole 5 gallon batch when I had the same problem once.
 
I added about 10 pounds of ice to the cabinet on my way out this morning, right after I put the airlock back in place.

That's normally enough to keep the box about 15-20 degrees cooler than the outside air for about 8 hours.

It still probably took a few hours before everything could cool back down to 70, which is why I guessed it was that hot for about 10 hours.
 
Sounds like you're getting back into desirable territory then. You're probably still okay given that you still have a ways to go for primary to finish out. Might have some esters, but I'm thinking you probably didn't ruin it. You'll have to keep us informed.
 
Got home and checked it again. The airlock had blown a second time, nothing near as exciting as the first one though.

The digital thermometer had in fact gotten wet, it was still reading 75* compared to the Fermometer that was reading 64* (I knew I used both for a reason)

Once it was dried off and retaped to the carboy it started reading its normal 2* below the fermometer (one of these days I will get around to recalibrating it to include the extra probe length.)

Here's a snapshot of the spatter that the airlock made on the top of my cabinet the first time it blew.

brown spatter

Judging by the smell of the cabinet I'll have to pass up on banana nut brown this time. I kinda want to make some now though.
 
Wow...you've to got love those airlock explosions. So it sounds like everything is good-to-go now. Glad to hear it!
 
I had almost the same situation the other day with an amber I racked onto a belgian cake. Ambient is about 64F, looked in the morning and the blow off tube was flowing yeast into its overflow like crazy, and the stick-on thermometer was reading over 80F. After it calmed down enough to switch to an airlock (and soak the blow off in oxiclean), the temp of the carboy had gone down to about 70. I really need to rig up a tub or chamber.
 
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