It got rather cold in my home a few nights ago (and last night), and although I have my carboy wrapped, I think I may have accidentally cold crashed this batch. I say accidentally because I pitched the yeast on Sunday, and today being Wednesday know it's probably not done yet (haven't taken a gravity reading yet, but fairly confident). I've shaken it up several times, but haven't seen any action. I know I can always repitch a bit and be okay, but I was hoping to wash the yeast. So I have 2 questions: 1) Ways to revive a batch that has viable yeast after a cold-crash? 2) If I repitch, does this have any effect on washing yeast?
1. Bring it inside and keep it in a room that's about 68-72F. If it's most of the way done fermenting, you've got your flavor profile pretty well locked in. Now you just need to shave a little bit of that sweetness off and get your FG down where you want it. 2. I wouldn't think so. You'll just have more cells that come out in the wash. Your original yeast wasn't hurt unless your beer froze. It will most likely want to kick back on when you warm them back up. What strain did you use? I'd wait for at least a week and 2 gravity readings (3 days apart) before I'd consider repitching.
BTW, when you cold crash you create a vacuum the other direction. Check your airlock, if you're using one. It may be dry.
Great note about the airlock! I had to add some water to it yesterday. It's a WL-01, which I love and I've been using this one tube-worth for almost a year (tlc does a lot for yeast). It's not all I have, but would hate to waste any.
I accidentally cold crashed a hef at high krausen last summer. And by cold, I mean below freezing long enough for the fermenting beer to get slushy. I thawed it out, warmed it up, gave it a few shakes, and the yeast went right on doing what they do. I can't say for certain it didn't affect the flavor, but the beer tasted pretty damn good, so it didn't hurt it too much, if at all. So just wait a bit. You'll be fine.
Update: Wrapped it up tight (so no sunlight), set by a southern-facing window that gets lots of light to warm it up... and, it's back. Thanks Incrisin for the help.
