Temp control after primary

[Maine-iac]

I currently have a temp controlled chest freezer. While this has opened up a whole new world to my brewing, the chest freezer only has enough room for one carboy. I have an oatmeal stout that has been fermenting for seven days. It's a snowy day and I want to brew another beer. My thought is that I can take my oatmeal stout out of the freezer and let it continue fermenting in the closet without temp control. I am hoping that temp swings after most of the sugars and comsumed will not be as detrimental at this point. Any thoughts?

[JSKC]

I'm very interested in this as well. Though I can keep the chest freezer at any temperature, taking the carboy out would introduce it to a window of about 78-82F, unless I used the bucket and ice method.

If I could ferment in the chest freezer for about a week, converting most of the fermentables, would the later portion of fermentation at the higher temperatures effect the flavor profile very much?

[DrYeast]

I'm sure that there are exceptions, but to my knowledge, you can start bringing the temperature up after about a week (ales) without really affecting flavors (provided that you're fermentation has progressed well and your yeast have calmed down, i.e. krausen has fallen).

It's beneficial to do a diacetyl rest at the end of the fermentation, which can be done by increasing the temp for a few days, or letting it sit at fermentation temp for a longer time after fermentation has slowed. This mops up precursors and cleans up your flavor. 78-80 might be a bit much, but I think that yeast warming up slowly is no problem. If your fermantation is nearly done, and you slowly warm up to room temp, whatever is left of your fermentation will finish and the yeast will scavenge precursors. As long as you don't let it hang around too long at 80, the flavor profile will be ok.

Cooling them back down will cause them to go dormant, so you should avoid that, but even lagers can be warmed to room temp before transfer to keg or secondary. The Brew Strong for fermentation temp control is a great resource.

[nathanm]

I've been doing this for the past 3-4 batches since i've got a small fridge that only fits one fermenter. I usually just move the new beer into the fridge w/temp control and move the week old beer next to it in the closet. No problems as of yet, but my closet is within 1-2 degrees usually of my fermentation temp (this month has been good weather for that).

[brewinhard]

78 degrees is pretty high for an ale to ferment at unless its a saison. If fermentation is complete it wouldn't matter AS much if there was still active fermentation going on. I would think you might just be better off giving your beer the full two weeks in primary in the chest freezer and package it, then replace it with a new brew ASAP. But, you could always try it once with taking the beer out and letting it warm up, and see if you really like the flavor/aroma of it or not. If the beer is just for your consumption then it only really matters what you think about it. But, if you are competing then definitely maintain the temps the best you can. Minor temp fluctations esp after fermentation is complete is not a big deal.

[Maine-iac]

Thanks, Brewinhard, that makes sense. I'll keep it in the chest freezer for the another week and then get my winter spice ale in there!

[jwatkins56550]

you need to control fluctuations after primary fermentation. Honestly, I would recommend spending some time and money and build yourself a son of a fermentation chamber. It really comes in handy, and you can never have too much fermentation room! I typically do this for beers going through their diacetyl rest and I need the room in the main fridge for fermentation.