WineXpert Fast vs. Slow fermentation

[Rocky]

I would like to hear the forums views on the benefits or issues with fast vs. slow fermentation. I am making four kits which I began on 2-3-25. The next morning, the fermentation was unimpressive but my cellar temperature was in the mid 60's F and I thought temperature could be a factor. I added heat to two of the fermenters and the process really took off. Today, 3 days after starting, one of the wines with heat had dropped from SGi 1.092 to SG 1.013 so I racked the wine off its residue (grape skins and oak powder and chips, etc.) into a 6 gallon carboy and added an airlock. I don't see a problem with this but I would like to throw it out to the community. Two other wines were SG 1.035 or so and will likely be below SG 1.020 by the EOD tomorrow. The third and largest batch is being more cooperative and is sitting at about SG 1.060.

Just wondering what you all think. Thanks for your consideration.

 

[Rice_Guy]

* high temp increases nutrient demand and increases the risk of off flavors / yeast stress. I have seen SO2 production when at 35C.
* high temp is said to be responsible for blowing off fruity aromatics.
* the yeast are hearty buggers they will do their job at faster rates up until death.
I have done 40C and it was 3 days for dryness.
* fusil alcohols, off flavors.

 

[Rocky]

* high temp increases nutrient demand and increases the risk of off flavors / yeast stress. I have seen SO2 production when at 35C.
* high temp is said to be responsible for blowing off fruity aromatics.
* the yeast are hearty buggers they will do their job at faster rates up until death.
I have done 40C and it was 3 days for dryness.
* fusil alcohols, off flavors.

Wow, you're just full of good news!

I did not get that high, maybe hit 25 degrees C.

 

[winemaker81]

With overnight starters I get a faster ferment.

But, upon reflection, do I? An overnight starter gives the yeast a larger critical mass, so it can dominate the must quicker. A large part of the reproduction is done in an environment that is more to the yeast's liking.

Without a starter, it typically takes a day to notice fermentation, and another day (or two) for it to get vigorous. So what seems like a longer ferment may actually more a longer soak.

I've learned to like a colder ferment, as I do get more aroma. Reds can be too fruity for my liking, but barrel aging dampens that.

Last fall I left the reds in the fermenter for 2 weeks, so I had a short EM. Great for color and tannin, although I use Color Pro so color and tannin are good, anyway.

I'm just spitting out facts/ideas. I haven't conducted qualitative tests to determine if one method is actually better than another.

 

[sour_grapes]

On the plus side, a hotter fermentation is purported to extract more goodness from the skins.