2nd fermentation temps

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Junior Member
Dec 26, 2014
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Hey folks,

I placed my carboy in a room for secondary fermentation that is only 64ish... should I have placed it in na warme room? It's a red kit. It's been in there now for about 4 or 5 days. Last SG reading was .997

Is it too late to increase the temps?

By "secondary fermentation" do you mean MLF, or to let the wine complete fermentation (assuming it's not done at 0.997).

Assuming the latter, IME it's best to keep the wine at a stable temperature until I'm sure fermentation is complete. A drop in temperature can stick the fermentation, and a corollary to Murphy's laws says that the ferment will start again at the most inconvenient point.

How large is the temperature drop?
I am referring to a secondary fermentation and not an MLF. The temperature during primary fermentation was 70. It's now sitting at 63. I guess 7 degrees is pretty big drop?

Should I bring it back to 70?

I am referring to a secondary fermentation and not an MLF.

Since your gravity reading is already at 0.997, what are you expecting to be fermented during the secondary fermentation? Typically that term refers to malolactic fermentation, which progresses in sequence after alcoholic fermentation.

In that case, you want the wine to hover around 70ºF to encourage MLF bacteria to get going, whether you've inoculated with it or are relying on what's already in the wine.

Even if the wine is not completely dry at 0.997, lowering the temp into the 60s is likely to make the yeast sleepy. You'll want to keep it warmer til you're certain all yeast activity has finished.
I didn't inoculate it. It's a kit. Do people do MLF with kits, typically?

I think I will bring it up to 70 to be on the safe side for the rest of the week to make sure the yeast is completely exhausted. Also, was hoping to get as dry of a wine as possible. So, I suppose closer to .994 or lower... but maybe .997 is fine. Taste is fine but hard to tell. Seems like it could be a touch drier.

I didn't inoculate it. It's a kit. Do people do MLF with kits, typically?
A few people have tried it, and IIRC, the results were mostly poor. Kits are supposed to be balanced for acid, and MLF messes with that -- replacing malic acid with lactic acid. If a grape wine is high in malic acid, this softens the acidity and produces a buttery flavor, but in kits it removes the bite and makes the wine insipid. Personally, I'd not do it.

A lot of references refer to the continuation of fermentation after pressing/first racking as "secondary fermentation". This is not correct, as there is just one fermentation, and the yeast don't care if the wine has been pressed/racked. As @Flufnagel noted, MLF is commonly referred to as secondary fermentation.

Yes, bring the wine back up to 70 F, and I'd give it a good stir (don't make it foam) to mix up any sediment. This will often spur yeast to continue eating.

Note that you have no control over the FG. The SG is specific gravity, which is the density of the liquid and is affected by the amount of alcohol, sugar, and other constituents in the wine. While we commonly consider SG as the measure of sugar, that's not the only thing. If it was, SG would stop at 1.000 and never go lower.

The wine can be perfectly dry at 0.998 or 0.999. I have 2 FWK Forte kits in barrel at 0.999 right now -- both are bone dry, but the SG is what it is.
Also, you don't need a paddle to stir at this point. You can use a simple racking cane; insert it all the way, and sweep it around the bottom circumference of the carboy. That will get most of the lees into suspension.
As @winemaker81 said, there is only one fermentation. But there is a secondary fermentation vessel. Many of us rack the wine from a bucket into a carboy once the SG is below 1.010. That is sometimes called "secondary fermentation," but it is really just the continuation of fermentation in a different container.
I waited until all visible signs of fermentation were absent. The Sg was around .998/.997 - hard to tell sometimes. But definitely below 1.000. I think I am going to have a very strong wine! I started at 1.110
stirred the bottom this evening,.. temp at 71

I'm going to leave it alone for 5 to 7 days.. see how it settles and take another reading.. maybe by weekend