Exothermic

[Billaban]

Greetings,

I have been brewing beer for many years and had never been aware that fermentation is exothermic. Ambient temps in various rooms have always done me well for brewing.

I started my first wine kit today. The slab floor in my unfinished basement in MD today is 46 degrees. I made a insulated enclosure w/ plywood and 2x4s and obviously insulation. Perhaps most importantly a insulated base for the enclosure to get off the slab floor. Additionally I'm using a FermWrap heater w/ a Johnson controller to hopefully maintain 72 degrees.

So I'm wondering about a exothermic fermentation, i.e., if I have insulated too well will my temp actually climb beyond the desired range? I suppose the only solution is to monitor temp and remove the lid of my enclosure if the temp rises.

 

[sour_grapes]

Yes, fermentation is exothermic. I personally have not witnessed any effects of this, although on this forum I have read many people who reported they can keep a decently high temperature in their must during fermentation by using blankets around their fermenting bucket. I have heard only a few, very few, accounts of fermentation buckets getting too hot due to the reaction. (Of course, this can be a problem in a commercial winery, with much larger tanks, but not often a problem in the home.)

Bottom line: I think you are correct, the only solution is to monitor your temperature. But I also think that at 46 F ambient, you will have no problems getting too hot, even with a well-insulated box. I think your FermWrap will be on more than it will be off!

 

[Billaban]

>>> I think your FermWrap will be on more than it will be off!

That appears to be the case. Currently only managing to hold 70 degrees this morning. I have added more insulation.

 

[jamesngalveston]

Last year i made a fig wine, about 60 lbs of fresh figs for a 3 gallon batch. I started with about 5 gallons of must, becuase I knew I would loose about 1 to 1 1/2 gallons for lees.
ambient room temp was about 73 degrees, as well as the must.I use a very good digital thermometer.
During fermentation the must got to 105 degrees....so much so that i put fans around it to cool it down....

 

[Billaban]

I have 12 gallons (two kits of WE Chianti) in a 13 gallon carboy. This is my first batch. I have one fermwrap which goes about 1/2 way around the circumference and a Johnson controller. The sensor is taped to the middle of the carboy on the far side from the fermwrap.

I have never liked using plastic for my home brewing and that has carried over to this new adventure with wine.

I started yesterday and this morning the heater was on and the temp was at 70, i.e., 2 degrees below the setpoint. I was right on 72 last evening when I pitched. I added more installation inside and on top of my enclosure this morning and it has recovered to 71. So far.

I have an old house w/ an unfinished basement. It is mighty cold these days here in the MD suburbs of DC. I think my summer time temps in the basement will be well suited for future batches. I have 3 of these monster 13 gallon carboys so I could easily do two batches each summer. Hmmm. I think I have a plan.

 

[Billaban]

FWIW -

Much to my surprise my thermal enclosure in conjunction w/ the exothermic reaction has my 12 gallon batch holding temp with very little evidence of the heater actually running despite almost 30 degrees difference between ambient temp and the thermostat set point. Interesting. I would have bet money that the heater would be running frequently to maintain a delta that large. Nice.

 

[sour_grapes]

FWIW -

Much to my surprise my thermal enclosure in conjunction w/ the exothermic reaction has my 12 gallon batch holding temp with very little evidence of the heater actually running despite almost 30 degrees difference between ambient temp and the thermostat set point. Interesting. I would have bet money that the heater would be running frequently to maintain a delta that large. Nice.

Well, that is great! As you know, I predicted it would take more heating to maintain that temperature. You must have done a great job insulating.