Legend tells of a beer most foul, which when loosed from its growler, scorches the nostrils of any who dare to drink it.
This prophecy was fulfilled, and my growler batch was virtually undrinkable. There was a distinct smell of sulfur that was tolerable at first but became overwhelming after the first few sips. From what I have read, the sulfur smell is a common symptom of yeast autolysis, which is probably the most likely culprit given the circumstances.
The beer was given about 1.5 weeks to ferment, and another 1.5 weeks to carbonate—3 weeks is a fairly young beer, but in this case, the beer was sitting on the yeast cake for that entire time. Most resources recommend no longer than 10 days on the primary yeast cake.
I was aware from the outset that this could be a possible spoiler in my experiment, but there is a lot of controversy about autolysis. The 10-day rule seems to be pretty common received knowledge. After that point, the theory goes, the yeast begin to cannibalize themselves and contribute off flavors; thus the need for a secondary vessel for longer fermentations. On the other side of the debate, there are those who claim that the effects of autolysis are overblown. It’s not that it doesn’t occur, or that it doesn’t effect the beer, but rather that the yeast eventually clean up their own byproducts and the off flavors dissipate over time. Thus, they claim, a long fermentation can just as easily be carried out all in one vessel.
I was turning all this over in my mind while pouring the remains of my sulfury beer down the drain, and then a thought occurred to me: I have one more growler of this stuff, so I have a good way to test for autolysis. At data point one (this beer), the effects of autolysis were obviously evident. But I have another growler full of the same beer, sitting on the same yeast cake, which I can open a couple weeks from now to get data point two. My growler batch experiment has turned into an autolysis experiment.
There is actually a lot to be hopeful about. As you can see to the right here, it was a pretty good looking beer, pretty well carbonated, and with a good flavor (at least as much as I could detect through the smell). If the off flavors do indeed take care of themselves, then the growler batch may still be a viable system.