What temperature kills yeast

[RokDok]

Brewed this morning, my yeast cultures were sitting on top of the washing machine, and Mrs Rok Dok had put a load on. Yeast felt a bit warm and when I took the temp of the top of the washing machine it was 39.7. Have I murdered the yeast at this temp ??? Am I guilty of yeasticide and will I have to reculture more yeast ??? RD

 

[iceo]

dont think you will have killed the yeast but it wont be happy and give you off flavors

 

[rpt]

Yeast shouldn't be killed until about 60C or so IIRC. Whether it has been harmed or will cause funny flavours, I'm not sure.

 

[RokDok]

Thanks guys, that is reassuring. The volume of each culture was about 200 ml and the temperature was only that high for about an hour so off flavours should be a minimum, I hope. Main thing is that is is still viable, anyway it's been pitched and we'll see what the outcome is tomorrow.