Temperature Fluctuation During Fermentation

[arcticsid]

Heres an interesting question for you. I know many people who use wood heat as their exclusive means of heat for their homes/cabins. Several have said they would like to try their hand at making wine, but are concerned about the temp fluctuations. It may be 75F when they leave for work and may be 50 when they return. How much of this sort of fluctuation will adversley affect the whole fermentation process? I used to live in the "woods" and watched my Dad make wine while living with a woodstove, it was more like "hooch" then wine, but it did seem to work, even though the longest any batch was aged was as long as it took to drink Any thoughts on this?
Troy

 

[Wine Maker]

Is there a place in your house that has a somewhat constant temperature? That would be the ideal setting. What you really need to focus on is not so much the ambient temperature of the room (although it will be a factor) but rather the temperature of the must (fermentation). Yeast produce a lot of heat during fermentation. Commercial yeast has various fermentation ranges, for example RC212 has a range of 59F - 86F, if the must temperature gets above or below this range then the yeast can die off and you end up with a stuck fermentation. If the must temp gets close to or above the high range you can use ice to cool down the temp.

In October I fermented 50 gal of Zinfandel in my garage. We had a cold spell and overnight temps dipped into the low 30's, the high for the day ranged from low to mid 50's. Knowing that October is an iffy month for cold where I live I purchased two types of yeast. One EC1118 had a low range of 45F, the other 59F. I went with the EC1118 and had good results, a few days my must was pushing 50F but the yeast continued to work, albeit slowly. I would not be so concerned with the 50F temp of your house because the fermentation will likely keep the must temp in the 60's or 70's, but be concerned with the 75F. You will need to find a yeast that works well in the higher range (again we are dealing with the temp of the must not the ambient temp) and keep a careful eye on the must temp. When a yeast struggles at the higher end of the range you can not only end up with a stuck fermentation but also the strain on the yeast can produce hydrogen sulfide, which is a rotten egg odor.

Hope this helps.

 

[Wine Maker]

I forgot to address the issue of storing wine in areas with fluctating temps. In my opinion, if you are storing wine for a relative short time, 6 months to a year, I wouldn't be so worried about temp fluctuations. Temperature fluctuations of 10F over time will have an effect on aging, in essence it will cause the wine to age much more quickly then desired at constant ranges. If the wine tasted like hooch, it was most likely from the process and not the temp fluctuations.

 

[arcticsid]

Thanks for your response, curious to see what others will add
Troy

 

[phermenter]

I'm pretty new to this game, but everything I've read suggests the yeast aren't very happy stopping and starting as temps bounce around during fermentation. I can tell you for sure that when I was primarily doing beer, my beers weren't very good until I made the simple admustment of moving the carboy into a closet where the temperature was more stable than outside it. After that, bingo, all my efforts paid off.