Is 60 degrees too low for wlp 004 Irish Yeast?

[mrphillips]

I have a porter in the primary and after 4 days (4 EXTREMELY active fermentation days) I was considering slowly bumping up the temp from 60 to 70. I was very impressed with how the yeast handled 60 degrees, so I'm not sure if I'd be doing more harm than good by changing things around.

I know that a "diacital rest" (or whatever you call it in an ale) can help wrap things up the last few days of fermentation, but I plan on keeping it in the bucket for another 1.5 weeks - no secondary. Will this yeast throw some weird estery curve ball my way if I keep it at 70 for another 10 days?

 

[friarsmith]

Since the yeast is apparently happy, I would recommend holding steady at 60* until day 6 or 7 then raise the temp 5* for a few days, then another 3* to 5* for the last few days before transfer. That should burn off any diacetyl, finish up fermentation, and give a little time for the yeast to flocc out. After your two week PF, you might want to consider crashing the beer at 40* or so for a few days before racking.

 

[helibrewer]

You can very safely bring it up 2 degrees per day. That yeast does produce a bit of diacetyl even in it's recommended range of 65-68.