The Danger of Belgian Yeast

As far as I know, there is only one: it can be extremely active. We were gone most of the day for Thanksgiving, and when we got home this evening this is what I saw:

Well, not quite. The right fermenter had an airlock installed and the lid was bulging up so far I was sure it would explode any second. So I quickly pulled it and installed the only blowoff hose I had, then took the picture. The left fermenter was also bulging so I pulled the airlock to let it deflate a little and quickly made another blowoff assembly, then went to work cleaning up all the yummy-smelling, disgusting-looking, blown-off yeast.

I had started these batches at 68 degrees, and when I took the picture they were at 78 degrees. I had briefly used a heating pad to get the temperature ramping up, but by this time it had been off for more than eight hours, so they were producing all that heat themselves. This batch being a tripel, I'm glad they got that warm because it will just mean more Belgian ester flavors (think banana). Once I got everything installed and cleaned up, it looked like this:

With these fermenters both blowing off into the same jar of dilute Star San solution, it sounded (according to the Fair Wx Runner) like the beer was having serious intestinal problems. Fortunately, that's not the case: that's some happy beer, and in three months there will be some happy folks drinking it.