Very active wine Shiraz

[Desmnd]

I added some 1kg of sugar to a beverdale Shiraz. I have done this in the past with other kits because the volume was lower than I liked. However, to my surprise it measured 110. That equates to 14.5% APV. I tend to put a heater in their which is set to 20C. I also put a duvet. To keep the temperature more stable across the fermenter and in winter it is needed.

After the first day it was bubbling over the sides of the fermenter. I don’t have one of those annoying bulb system and I can’t put the lid on the fermenter as the cable for the heater comes out the side. However, for cleanliness, I put a clean tea towel over the top with the duvet around it.

If it is bubbling over the sides this suggests that it is too hot. But as the heater will not be on, how. Can the fermentation process heat the wine over the temperature it should be at? I would have thought that it would self regulate, in that if the temperature increased the yeast activity would slow down.

I don’t think I have done any harm to the outcome but I am concerned about the over activity.

The SG dropped over 24 hours from 110 down to 60 and fermentation has settled done now.

 

[kelper]

Did you measure the temp in the FV. Maybe the heater 'stat is broken or inaccurate?

 

[Desmnd]

I did measure the temp. The heater is OK fairly new and has been used lot of times in beer brewing and checked. Never monitored temp when it was flowing over as I haven't got a very long temperature probe.

Can the fermentation drive the temperature VERY high. Compost heaps are very hot inside and temperature is increased during fermentation.

 

[kelper]

Mine go up about 2 celsius but I don't lag the bucket!

 

[Desmnd]

I lagged it so that the temperature would be more consistent all through. For example, if the temperature goes down the heater comes on. It will be a lot hotter around the area of the heater. This would increase as the heat moves out. Doing this keeps it more consistently the same throughout. Also in the winter time if the outside temperature is low. This can benefit.

f it goes out of control like this is it because...
A) The temperature is too high, or.
B) The amount of sugar (SG 110), requires more activity but not necessarily that it is hotter. IE jus simply over active.

Over activity would not degrade the wine but a high temp would, if you can get my meaning.