Fermentation Temp

[ALLYSON WATINs]

DISCLAIMER: So green (newbie) would make a geen apple take umbridge!

Making a red wine (cab) from a kit.

So to start when i pitched my yeast i was at 74 degrees, two days later the temp rose to 76 i was able to bring it back to 74 within a few hours. Does the consistancy of the temp affect the fermentation process, should i bring my temp further down?

 

[salcoco]

for red wine you are okay temp can go as high as 80 without a problem. white wines are the ones that are best fermented at 65.

 

[ALLYSON WATINs]

Awesome, thanks

 

[Scooter68]

The fermentation process generates a lot of heat, like a person running a race. While overly high or low temps should be avoided, you should expect some rise in temp. When the fermentation is roaring along especially.

As salcoco stated it not a big issue with red wines, but with white wine or fruit wines with delicate flavors and essences, lower temps help protect you wine from losing those qualities. Just avoid large temp swings (10 degrees or more).

If you feel the fementation vessel in mid-ferment you will notice the warmth.

 

[Gotwater121]

Hi, I’m new to the forums and home wine making too. I just started a Winexpert kit “Malbec with grape skins” 3 days ago. The temp on it now 3rd day in is at 80*F. Should I try to cool it to a lower temp or keep it at 80? Thanks

 

[NorCal]

I was speaking to a local commercial winemaker, whom a few years ago had the highest rated Syrah in the nation. He lets his fermentations run to 90+ degrees by design. It was hard to argue with him with his Wine Spectator award on the wall. @4score's best of show Barbera at the CA state fair hit well over 90 degrees (not on purpose) and had to be brought back down to earth with dry ice. My red fermentations typically peak around 85 degrees. In general though, I like @salcoco's 80 degree target for reds, especially with making wine from a kit, you want to steer down the center of the lane.

Understanding what the fermentation temperature is doing to your ferment, based on your grapes, nutrient, yeast and desired outcome is key. If I had great fruit, I'd want lower ferment temps to get more time on the skins and better extraction. Bad fruit, I'd want a short hot ferment, to get it done as fast as possible.

 

[Ajmassa]

DISCLAIMER: So green (newbie) would make a geen apple take umbridge!

Making a red wine (cab) from a kit.

So to start when i pitched my yeast i was at 74 degrees, two days later the temp rose to 76 i was able to bring it back to 74 within a few hours. Does the consistancy of the temp affect the fermentation process, should i bring my temp further down?

You can expect the temperature fluctuation to move pretty close the same rate as the sugar being consumed/your SG dropping.
After a day or so activity is just beginning, but by day 2-3 there’s a significant increase in SG drop/temp rise. And will continue for a couple days.
Typical for me is day 1-2 about 70°. Days 2-5 gradual rise, peaking in low to mid 80’s. And days 6,7,8.... will be a gradual drop back to room temperature as fermentation completes. (Just a rough general estimate to give you an idea of what to expect)

 

[Ajmassa]

And even if you look up your yeast tolerances and see the temp listed at say 82°, that doesn’t mean it will die if that temp is reached.
The max temp before yeasts start dying changes when alcohol is present. It could be 105° at the start even. By the time the max temp is in range to be effected, the abv is already significant, meaning it would be towards the end of fermentation and temps would have already cooled off.

 

[Scooter68]

Another point is that if you are trying to get fermentation started and you are at either the high or low end of a yeast's temp tolerance it may take longer to start or not even start. That has proved to especially true at the low end of the range. After fermentation starts you should find fewer problems. BUT that also assumes that all other factors are not on or over the yeast's tolerance especially acidity and SG.

 

[Zintrigue]

I was speaking to a local commercial winemaker, whom a few years ago had the highest rated Syrah in the nation. He lets his fermentations run to 90+ degrees by design. It was hard to argue with him with his Wine Spectator award on the wall. @4score's best of show Barbera at the CA state fair hit well over 90 degrees (not on purpose) and had to be brought back down to earth with dry ice. My red fermentations typically peak around 85 degrees. In general though, I like @salcoco's 80 degree target for reds, especially with making wine from a kit, you want to steer down the center of the lane.

Understanding what the fermentation temperature is doing to your ferment, based on your grapes, nutrient, yeast and desired outcome is key. If I had great fruit, I'd want lower ferment temps to get more time on the skins and better extraction. Bad fruit, I'd want a short hot ferment, to get it done as fast as possible.

I'm really glad you posted this. My house is hot, my wines ferment around 84 in the summer, and I was wondering if I was shorting myself on extra flavors lost by the heat. Guess I'm alright. Thanks for the info!

 

[Johnd]

I'm really glad you posted this. My house is hot, my wines ferment around 84 in the summer, and I was wondering if I was shorting myself on extra flavors lost by the heat. Guess I'm alright. Thanks for the info!

That DOES NOT apply to whites or delicate rose’s at all. In fact, unless you have skins in your kit, lower temps are better.

 

[NorCal]

That DOES NOT apply to whites or delicate rose’s at all. In fact, unless you have skins in your kit, lower temps are better.

Yea, good point , I should have noted that. I’m able to keep my white ferments in the 60’s, mostly because I make smaller batches (500 lbs) and I can ferment in my wine box.

 

[Zintrigue]

That DOES NOT apply to whites or delicate rose’s at all. In fact, unless you have skins in your kit, lower temps are better.

I don't do whites or roses, but if I do I'll have to figure out how to cool that ferment down. Thanks

 

[BigH]

I don't do whites or roses, but if I do I'll have to figure out how to cool that ferment down. Thanks

I cope with this problem by not starting white wines until after Halloween. I freeze all of the juice I press during harvest. I thaw when the temperatures in my high tech wine making facility (ie the basement closet that my wife confines my winemaking to) are in the low to mid 60s.

H

 

[NorCal]

I cope with this problem by not starting white wines until after Halloween. I freeze all of the juice I press during harvest. I thaw when the temperature in my high tech wine making facility (ie the basement closet that my wife confines my winemaking to) are in the low to mid 60s.

H

Interesting. Does freezing the juice effect the end wine quality?

 

[Zintrigue]

I cope with this problem by not starting white wines until after Halloween. I freeze all of the juice I press during harvest. I thaw when the temperature in my high tech wine making facility (ie the basement closet that my wife confines my winemaking to) are in the low to mid 60s.

H

I wish that were an option for me! I wish they made cooling belts instead of heating belts.

 

[BigH]

Interesting. Does freezing the juice effect the end wine quality?

I first adopted this strategy in 2017, so I guess the jury is still out. I struggled with fermentation temps in 2016. Two of my whites are harvested in early August when it is well above 70 degrees in my basement wine closet. I have bottled about half of my 2017 whites. So far so good. I am repeating the freezing process this year. I figure if white wine kits consist of frozen juice, then I should be able to do the same.

Freezing does seem to help settle out solids, so I end up fermenting pretty clear juice. But some of those solids may provide nutrients. I freeze in 1.5 gallon containers that look like ice cream buckets. I try to put a layer of CO2 on top of the juice before I seal up the container and freeze them. One added benefit of this process is that I really can't cope with all of the grapes that I harvest inthe limited space that I have. I vinify the reds right way, and freeze the white juice. By the time I thaw the whites, the reds are in carboys and well into MLF. This staggered approach makes life easier and gives me the fermentation temps that I want for the whites.

Lastly, I have one variety called Brianna that I destem and freeze whole berries. I do this to improve juice yields.

H

 

[BigH]

I wish that were an option for me! I wish they made cooling belts instead of heating belts.

Before I adopted the freezing approach, I tried to cool my whites by putting the fermentation buckets in big plastic tubs filled with a few inches of water. I would add a bit of ice to the water and drape towels over the sides of the buckets that I kept moist. Not sure if I would call this strategy a raging success, but the wines turned out ok.

H

 

[bstnh1]

There is no advantage to fermenting a white kit at a low temperature. The purpose of low temperature fermentation for whites is to preserve delicate florals and other notes. These are destroyed at higher temps. Kits are pasteurized at 160°, so the delicate fragrances are destroyed in that process. If you're making white wines from grapes, you can preserve these aromas if you pick the grapes when cold and maintain a cold temperature throughout the entire process.
The following is from winemakermag.com, article by Tim Vandergritt

While it’s true that some white wines benefit from cool fermentation, that’s a very small percentage of wines that are made. The idea behind keeping it cool is that the very most delicate and volatile aromas (from very low-weight molecular compounds) which contribute that top 1% of the aromatic nose of a wine can be blown off of a fermentation that is too vigorous or too warm. But this only applies to grapes that have been picked cold, transported cold, crushed cold, and kept cold at every single step of the way. Let it warm up for even a short time and those low-weight molecular compounds are simply gone.

Consider a wine kit for a moment. The fruit is picked cold, of course: hot grapes oxidize quickly and the juice spoils. Pressed cold, sure — nobody heats a press or puts it anywhere but in the shade. Also pumped, transported and blended cold, as this keeps down spoilage at every step of the way. But at some point the juice is going to go through a pasteurizer and hit 160 °F (75 °C) before being cooled back down for packaging. You can see where this breaks down the whole cold-alla-time ideal.
https://winemakermag.com/article/813-maintaining-fermentation-temperatures-wine-kits

 

[4score]

We seem to battle heat during most all of our ferments these days. Dry ice, ice bombs, etc. and we still hit the 90's. Decided last year to get a yeast that can thrive in the hot temps and high alcohol readings. 80 degrees would be a God-send!