Dual Purpose Kegger

I have a small deep freezer that I have converted to a keg cooler. It has a ranco controller that keeps the temp at about 40degrees. I have been battling keeping my fermenting beer at a near constant temperature and I am wondering if there is any down side to raising the temp on the kegger up to around 68degrees for a couple weeks to ferment some beer?
Would the increased temperature damage the other beer in the kegs in the cooler?

Thanks

I did that before I got a proper set up. I didn't see much in the way of flavor/aroma stability issues, but I also wasn't taking notes about the process.

It won't hurt your beer in the least. It will probably even help it. It is a myth that temp changes will ruin a beer that's already been fermented. If anything, your beer will condition a bit faster at 68, so you will be effectively back to bulk conditioning and likely end up with better beer on the other side as long as they are not low ABV or wheats/Hefes. Anything hoppy is going to lose hop aroma/flavor/bitterness over time, but not particularly faster at higher temps.

You will be fine, especially if it is just for a few weeks. Good luck!

TopherM said:

It won't hurt your beer in the least. It will probably even help it. It is a myth that temp changes will ruin a beer that's already been fermented.

Click to expand...

Dr. Charlie Bamforth (UC Davis) would like a word with you. He seemed to disagree when he was on Brew Strong (The Brewing Network).

Well, like almost everyone else on this forum, my knowledge is limited to personal experience and the anecdotal experience of others.

If the good doctor from one of the actual respected brewing programs in the country has emperical evidence, I certainly defer!

TopherM said:

It won't hurt your beer in the least. It will probably even help it. It is a myth that temp changes will ruin a beer that's already been fermented. If anything, your beer will condition a bit faster at 68, so you will be effectively back to bulk conditioning and likely end up with better beer on the other side as long as they are not low ABV or wheats/Hefes. Anything hoppy is going to lose hop aroma/flavor/bitterness over time, but not particularly faster at higher temps.

You will be fine, especially if it is just for a few weeks. Good luck!

Click to expand...

Apparently, you have not had an oxidized beer. Try putting a beer in the heat, then in the fridge, and then repeat several times. It ain't good.

Doing it once and only going to 68*? You'll be fine. But saying that it's a myth as a whole is not right.

What does oxidized beer have to do with this discussion? The question is warming & cooling cycles.

SpeedYellow said:

What does oxidized beer have to do with this discussion? The question is warming & cooling cycles.

Click to expand...

Warming and cooling (temperature fluctuations) of beer will oxidize it. You know, make it taste like cardboard.

BJCP Flash Cards <-- scroll down to "Cardboard"

TopherM said:

Well, like almost everyone else on this forum, my knowledge is limited to personal experience and the anecdotal experience of others.

If the good doctor from one of the actual respected brewing programs in the country has emperical evidence, I certainly defer!

Click to expand...

I have not seen any evidence in this thread yet. Just some name-dropping. In this case I'm more inclined to go with your anecdotal evidence than someone who is making an assertion based on second-hand knowledge, even if it is a college professor.

broadbill said:

I have not seen any evidence in this thread yet. Just some name-dropping. In this case I'm more inclined to go with your anecdotal evidence than someone who is making an assertion based on second-hand knowledge, even if it is a college professor.

Click to expand...

AmandaK posted BJCP flash cards if those are good enough. Charlie Bamforth also worked for Bass and Budweiser, if that counts.

broadbill said:

I have not seen any evidence in this thread yet. Just some name-dropping. In this case I'm more inclined to go with your anecdotal evidence than someone who is making an assertion based on second-hand knowledge, even if it is a college professor.

Click to expand...

If you want the primary source, you can either go to the link I posted or listen to the BN Podcast.

AmandaK said:

Warming and cooling (temperature fluctuations) of beer will oxidize it. You know, make it taste like cardboard.

BJCP Flash Cards <-- scroll down to "Cardboard"

Click to expand...

My reading of those flash cards is that this cardboard oxidation is, by definition, due to oxygen in the headspace, and the solution (as shown on the cards) is to properly purge the vessel / bottle. If the OP follows proper purging procedures, this is a moot point.

Thanks for the podcast tip, probably worth hearing. If Bamforth says that temp fluctuations cause off flavors even in a properly purged container, I'd like to hear the reasoning.

SpeedYellow said:

My reading of those flash cards is that this cardboard oxidation is, by definition, due to oxygen in the headspace, and the solution (as shown on the cards) is to properly purge the vessel / bottle. If the OP follows proper purging procedures, this is a moot point.

Click to expand...

Very true. While temp flux "oxidation" isn't by definition caused by oxygen, it can exhibit the same flavors. A bit confusing though.

My understanding from the BN Brew Strong podcast with Dr. Bamforth on oxidation was that it was not the change in temperature that was the problem, it was that for every ten degrees cooler the beer was stored the life time doubled for a fixed oxygen concentration. I think think the units for the temperature was C, but it's been a while. Also there was a caveat that the beer should stay below approximately 90F.

I believe his message was that oxidation could be battled on two fronts: keep oxygen out of the package and store the beer cold to slow down the oxidation process.

Please, some one listen to the podcast and get the correct numbers and units... it has been a while since I listened to it.

OP: I also think your beer will be fine. I bottled two bottles from a keg via a picnic tab. One sat at 72f on a shelf and the other in fridge for a month. I noticed a slight difference in carbonation but not much else. I think that I didn't let the room temp beer cool down enough, causing the carb difference.