Regardless of the season, San Francisco is almost always between 50–70 degrees. So, the past few days have been a surprise. It’s been in the 80s (reaching 90s at some points) during the day and it’s even been warm at night.
When I went to check on my no-additive kit attempt last night, I was met with another heat related surprise. I had left a very small amount of headspace in the carboy with the intent of reducing oxygen exposure. There was maybe an inch to an inch-and-a-half of space there. But, last night, that space was gone and the wine was creeping up the airlock tube. Judging by the color of the water in the airlock, it had also overflowed at some point.
The wine had been degassing on its own, so there was a constant few bubbles on the surface. But, last night, not only was the volume greater, but it almost looked fully carbonated with a constant (though not strong) stream of CO2 bubbles rising up the now full airlock tube.
I took the airlock out, and the wine fortunately did not come spouting out as I had half-feared, and I emptied the water from the airlock a bit. Today, I’m thinking I’ll re-sanitize the stopper and airlock just to be safe.
I’m guessing that this is from the heat causing the expansion of both the wine and the carboy glass, accelerating the degassing process, and maybe even getting a bit of fermentation going again.
This has me super curious about what the effect will be. Will it ruin this batch? Is it sparking a new phase of development I would not otherwise have achieved?
Update: When it cooled down again, the level went back down.