Temperature of secondary fermentation

[Brewski]

hi all! i haven't been on this site in almost a year, but recently made a return to brewing and have a question for ya's... so me and my friend made an imperial stout last weekend, which fermented all week. it stopped bubbling yesterday, and today i transferred it over to a glass carboy for the recommended 4 months of secondary fermentation. i realize that not everyone is a proponent of secondaries, but we decided to go with it. i filled the carboy to the brim, to ensure that there won't be much room for oxygen to sit (had issues with this in the past, the secondary got moldy and i was told that i needed to fill it up all the way to eliminate or reduce the amount of oxygen that is in the secondary).

anyways, now that you have the background... i kept the temperature between 65-70 throughout the primary fermentation, should i stay within this same range for the secondary? since the yeast has already done it's thing (for the most part, at least), is temperature even a factor at this point? i live in the northeast, and sometimes our house gets cold during the day while i'm at work, so i'm basically just wondering if it will be a problem if the temperature ranges down to around 60 at times during the secondary.... any thoughts are appreciated, thanks all!

[brahn]

I don't think temperature control at this point is as important as during fermentation. I still wouldn't let it get any warmer than 70, but going below 65 won't be a problem at all. In fact, I would say the cooler the better.

[Brewski]

colder the better? no problem there! so, just to be clear, if i put this carboy in my basement (which gets pretty chilly, probably 50 degrees or below at times), this wouldn't be a problem?

[brahn]

Did you take a gravity reading when you racked it to secondary? If it's at it's terminal gravity already I think the basement is probably the best place for it. I wish I had someplace where I could store beer that cold without it being in a refrigerator!

[Brewski]

no, i actually completely forgot about the hydrometer reading before pitching the yeast, so i didn't do a reading after primary either... damn. this was my first brew in a while, so i was a little sloppy... thinking about it now, i probably should have left it in the primary for another few days, but it was done bubbling and for some reason i was anxious to transfer it over. live and learn.

is that part about empty space in the carboy accurate? i was told to make sure the carboy is completely filled for the secondary, even if you need to add water to fill it up, b/c oxygen in that empty space can cause contamination? true or false?

[lars]

is that part about empty space in the carboy accurate? i was told to make sure the carboy is completely filled for the secondary, even if you need to add water to fill it up, b/c oxygen in that empty space can cause contamination? true or false?

No, not really. You wont get an infection (mold or otherwise) from having headspace in your fermenter. You will only get an infection from poor sanitation practices. There is a benefit from reducing headspace (less exposure to O2) but you can also flush the headspace with co2 for a similar benefit. Personally, I think the filling a carboy to the brim when you are not 100% sure the beer is done fermenting (this can only be confirmed through accurate hydrometer readings) is a recipe for a big mess.

[BrewMasterBrad]

is that part about empty space in the carboy accurate? i was told to make sure the carboy is completely filled for the secondary, even if you need to add water to fill it up, b/c oxygen in that empty space can cause contamination? true or false?

No, not really. You wont get an infection (mold or otherwise) from having headspace in your fermenter. You will only get an infection from poor sanitation practices. There is a benefit from reducing headspace (less exposure to O2) but you can also flush the headspace with co2 for a similar benefit. Personally, I think the filling a carboy to the brim when you are not 100% sure the beer is done fermenting (this can only be confirmed through accurate hydrometer readings) is a recipe for a big mess.

As Lars stated, I would be more concerned about sanitation than headspace in the secondary. As long as you have a reasonable amount of headspace, your beer should have a layer of CO2 on top of it that will protect it from oxidation. Depending on the state of the yeast, the CO2 could come naturally, or you can flush your carboy with CO2 before filling it. CO2 is heavier than air, so it will settle on top of the beer and protect it from the oxygen in the air.

[maltbarley]

Brad, can you move this thread to technique?

[BrewMasterBrad]

Brad, can you move this thread to technique?

done