OMFG, did I kill my yeast?

:smack:

Here's the story. I've been milking the fermentation of my belgian saison with Wyeast 3724. I'm using a FermWrap, a digital temp control, and a thermowell. The beer has been at a steady temp of 93°F, basically for 60 days. I've been taking refractometer readings and the gravity has been slowly dropping, in character for this yeast. The last two readings were finally very close, so the beer attenuation was sputtering out. Not positive what the wort correction factor is for my refractometer, but I estimate about 85% attenuation.

I last checked the beer 2 days ago. Today, while I was in my basement, I noticed that the temperature probe was not in the thermowell; I left it sitting out since I took my last reading. I.e., the probe was reading the low ambient temps, and thus the FermWrap heat has been ON for 2 days straight. I dropped the probe in and it read 105°F.

I suppose I'm not really worried about any off flavor contributions. What I am worried about is if my yeast is healthy enough to bottle carb now. Any thoughts?

 

It will probably carb just fine. If you're worried about it just add some neutral dry yeast like US-05 at bottling time.

Or if you want to know for sure, pull a sample and bottle it with the right amount of priming sugar and see what happens. If it doesn't carb you'll know you need to add some yeast.

 

From what I have read 105 is not hot enough to kill the yeast. Another way to check would be to take a sample and add some DME or even sugar and see if you get any fermentation. I would also say that after 60 days the effects of the hot temperatures would be minimal.

 

For ale yeast, and especially Saison, I think you are ok. A professional brewer once recommended 90+ and even into the low 100s, for a saison. If you DID kill the yeast, as per kh54s10, simply add more and finish it. Saisons are notorious for taking their time late in the ferment.

 

Pulling a sample, adding some sugar, and looking for a fermentation is a real interesting idea. In this case though, I might just add some fresh dry yeast just to hedge any risk. I'm not familiar with dry yeast strains. Is US-05 the stain to use, or something else? There's no way in heck that the dry yeast would chomp away at sugar the saison yeast left behind, right?

 

US-05 is very neutral. From what I've been told its the same as WLP-001 California Ale. I'm sure the saison yeast has eaten all the available sugars so no worries there.

You probably don't even need a whole pack of dry yeast. I'm on my phone so I can't find it easily but I'm sure there's a thread somewhere about how much to add at bottling time.

 

I figured the same thing, I'll probably only add half a pack or something. I'll research a bit though. I know that rehydrating dry yeast is common practice. But do you think it's necessary? I'd rather not worry about additional opportunities of introducing nasties with the extra step or rehydrating.

 

I doubt rehydrating your yeast will matter much in this instance.