Temperature, and Fermentation Time.

[vinny]

I have done some reading and I have a grasp on the variables and outcomes, but I am not currently setup for any temperature control other than summer and winter outside temps, and the amount of open windows.

I pitched all 4 kits on May 1. All are sitting at 24-26 degrees depending on the current state of activity. As I said, these all took off like gangbusters. The Cabernet Zinfandel started at 1.110 and after 72 hours it is at 1.036. 2 more days it should be under 1.000 and that's in the ready to rack to secondary stage for me. Nothing to volcano and they finish dry within days on average. I often wait till day 7-9 where they usually sit at .996-.994

This is pretty typical to all my ferments. I just thought I'd seek out thoughts and opinions. I have 3 reds, currently. The Cab Zin, I am aiming for a BIG red. The other two are my utility 6 week kits. The third is a Passport series Chardonnay.

I am just wondering who is letting nature take it's course and who is controlling temps and what you think of my reckless disregard?

Cheer's

 

[Rice_Guy]

I have the ability to control temperature with four liter batches. (3 Inkbirds)
With the current ferment in the basement at 16C I was measuring 20 on the ferment. The lazy way to deal with a fast ferment was put it on the porch overnight at 7C which dropped the ferment to 9. With daylight it moved to the garage and then warmed up to 12C.
If I ran an Inkbird on the garage fridge I could and in the past have run it at 10 or 15, ,,,, But today i would need to empty the top freezer. ,,, Did I say lazy? ,,,, Or is it that there are a few batches waiting in the freezer. ,,,, the current ferment was cleaning 24 liters of peach out of the freezer.

 

[ChuckD]

I am just wondering who is letting nature take it's course and who is controlling temps and what you think of my reckless disregard?

Most of my ferments have been fall and winter so I’m typically putting a small oil filled heater in the winery (aka downstairs bathroom) to bring the temp up to 70F for the first day or two. After the ferment is going I often reduce it to 65 or so.

 

[BigDaveK]

I've pretty much let Mother Nature have Her way for months, even with basement ambient temps in the 50's. The lower temp really didn't affect the duration of fermentation very much. Though given the opportunity I'd like to test different temps on simultaneous batches.

I don't do grapes but I've read that reds like warmer temps.

 

[winemaker81]

I, too, casually disregard temperature. Most of my fall grape ferments are in the 17 to 19.5 C range (63 to 67 F). When I sprinkled the yeast on top, ferments could take 3 or 4 days to start. Since I've been making the overnight starters, I can smell fermentation within 6 hours of inoculation, and I've had ferments complete in 4 days.

I've made white kits in January where the cellar temp is 14.5/58, and the ferment might take 3 weeks, but it completed.

If I had a stuck ferment, I'd warm up the wine, but normally I just let nature take its course.

 

[cmason1957]

I don't pay much attention to the temperature of most ferments. I do try to keep my whites a bit cooler by putting them directly on the basement floor and for a day or so I will pull my red wines from grapes out into the sunnier area of my walk-out basement. Other than those two things, whatever temperature it is in my basement in Missouri, during the ferment is good enough for me.

It will range from a high of about 66F during summer to a low of about 62F during the deep of winter.

 

[Bmd2k1]

I'm in Michigan, and my lower level ranges from 63F to 70F year long....typically in the mid60s. As long as I'm in that range, I figure I'm good to go.

Cheers!

 

[Rice_Guy]

The lower temp really didn't affect the duration of fermentation very much. Though given the opportunity I'd like to test different temps on simultaneous batches.

FYI; a juice bucket demonstration for the Vinters Club meetings

A fermentation rate temperature study
View attachment 75666

 

[cmason1957]

FYI; a juice bucket demonstration for the Vinters Club meetings

That chart is about what I would have expected. Were there any noticiable differences in the finished wines that could be traced back to fermentation temperatures??

 

[Jovimaple]

When I first started, I worried about temp and ended up with 3 heating pads and 2 Inkbirds. Now the only time I bother using the heating pads is if a ferment gets stuck, which is rare.

My fermenting space ambient temps range from 65° to 74° F.

 

[vinny]

That chart is about what I would have expected. Were there any noticiable differences in the finished wines that could be traced back to fermentation temperatures??

This is the big question for me. I am really not concerned about the reds, but I would be interested to see/taste the difference in a white.

 

[AR324]

I read an interesting article in Wine Maker Magazine about fermentation temps for kits. It said the rationale for fermentation at a cooler temperature for whites and to get a more fruit forward red don’t apply for kits the way it might for grapes. I think it was because kits have already been heated for pasteurization.

Seems like this would not apply for FWKs.

That said, your mileage may very.

 

[BigDaveK]

This is the big question for me. I am really not concerned about the reds, but I would be interested to see/taste the difference in a white.

That would be my interest, also. Though with me it would be dark berries.

These guys found an increase in phenolics, anthocyanins, AND tannin with higher temps. They're talking greater than 30C!
AWRI has a lot of good info.

https://www.awri.com.au/wp-content/...ation-temperature-on-red-wine-composition.pdf

 

[Raptor99]

@BigDaveK Interesting article. It seems focused mainly on tannins and phenolics that affect color. Not as much is said about flavor. Some yeast produce more esters at higher temperatures, which contribute to flavor. Increased glycerol concentration can improve body.

But on the other hand, at higher temperatures more of the volatile compounds that affect flavor are driven off. So it is a trade-off. I would guess that this is more of a concern for fruit wines with a more delicate flavor, such as pear. I know that some hard cider makers say that fermenting at a lower temperature preserves more of the apple flavor.

Out of all the outcomes, the speed of fermentation is the least of my concerns.

 

[BigDaveK]

@Raptor99 this is such a unique hobby. A person can follow a recipe and make a very nice wine. Or you can go in the rabbit hole a bit and realize you'll never know everything, ever, but it doesn't matter. The more I learn the more I want to experiment.

 

[Rice_Guy]

That chart is about what I would have expected. Were there any noticiable differences in the finished wines that could be traced back to fermentation temperatures??

The warmer temp has more off flavor as volatile sulfur.
Current reading would say that we could fight reductive sulfur with better yeast nutrition. I haven’t been the designated person to rerun a temperature experiment with TOSNA 3.0 so I can’t vouch for this. Gut feel is that a typical “northern hybrid” red grape off flavor is worse with higher temperatures.

 

[RylanJacobs]

Quick question:

Can an Inkbird temp probe be placed directly into the fermentation? Or should I tape it to the side of the bucket. Looking to keep accurate control of fermentation temps

 

[vinny]

Depends on what you have, some are waterproof, others not. You can pur it under the fermenter, tape it to the side, or put a thermo well in the bucket lid.

 

[wineview]

I tape mine on the side of the bucket. It’s usually a 2F difference than what’s in the bucket. I just factor that in.

 

[BigDaveK]

I tape mine on the outside as well. Depending on the time of year and ambient temps in the basement, I've noticed 2-4F difference.