Did my stir plate cook my yeast?

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ThreeDogsNE

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I bought a lab stir plate off of ebay a while back, but used it for the first time this morning. I am trying to propagate up a packet Wyeast Kolsch yeast for a 10 gallon batch. I boiled the DME last night, and pitched the packed this morning. Tonight I checked it, and it feels pretty warm. Check the temperature, and it's 97*! I just learned the hard way that these stir plates throw off some heat. I took the flask off the stir plate, and it's settling now.

Search did not show me a similar story. Has anyone had something similar happen? How did things work out? In other words, is my yeast okay, or is it back to dry yeast, or back to the LHBS?
 
You have to supply a manufacture and model number of the stir plate. I use two different stirrers and temperature might increase a little. Will heating yeast to 97° hurt? , yes...
 
Hmmm.... I have a home made stir plate and never had a problem like that. Perhaps the blades on the computer fan have a cooling effect. I usually just put the stir plate under the kitchen cabinets lights and i'm good to go.
 
If it was only 97F you're fine, but I would crash and decant because the starter wort is full of nasty flavours most likely. Maybe put a thin piece of styrofoam between your flask and the stirplate in the future.
 
These look like what I bought:

http://www.ebay.com/itm/K88453-2-Sy...532?pt=LH_DefaultDomain_0&hash=item4cff60d8cc

The price was pretty similar, and seemed like a decent deal. I like DIY stuff, but these looked like a bargain. There is no heat setting on them.

When I removed the flask and let it cool and settle, there did seem to be quite a bit of yeast in it. I put a piece of tile on top of the magnetic stirrer, and then an aluminum pan on top of that as a heat sink. I set the flask on top off all this after it had cooled. The stirrer still worked, so I left it running that way last night. The flask was cool this morning when I checked it. I will decant the "beer" and add fresh wort tonight, and see what happens. I still hold out hope for using this yeast this weekend.
 
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