Fermenting Temperature - a drastic change

[Galaxy_Stranger]

I just did a partial-extract Doppelbock. I put the fermenter in the bath tub and let it set for a day. The thermostat on the house is set at 71°. The temperature in the fermenter was creeping up on 75. I didn't want it quite that high, so I filled the tub with some water and dumped some ice in it - which quickly started to melt. I didn't think anything of it and went to bed. I mean - it's an entire bathtub with a little ice in it.

This morning I woke up and checked-in on it. The ice had all melted away and the yeast were still going to town. I checked the temp and it was 64°!!

My question is - what does a drastic change like that do to the beer? Will the yeast take it in stride, or will they start producing weird things?

 

[d3track]

The drastic change could (not guarantee) stall fermentation, but if its chugging away you should be good. I'd be more worried about it being 75+ early on. What yeast strain since you said it was a dopplebock?

 

[A2HB]

64 is exactly where you want it to be. Don't sweat it your beer is going to come out great if you can keep it around that range. It's when things get too hot that you have to worry about off flavors, but as long as you're in the low to mid 60's up to the low 70's (for ales) you're golden.

 

[hanuswalrus]

Which strain of yeast are you using?

Doppelbocks are, traditionally, lagered so you should be fermenting somewhere in the 50s I believe.

 

[Galaxy_Stranger]

Of course, you'd have to ask that...

It was a dry ale yeast, I don't recall what variety. I do remember that the packet stated that it didn't have to be activated or otherwise prepared - just dump it in the fermenter, which I thought was odd. I did warm it up beforehand. The yeast hasn't stopped churning since I started it up.

So, the change in temp isn't an issue? Just as long as it doesn't make the yeast go dormant? Awesome!