Last Friday I brewed some Oatmeal Stout. Some for friends, and some for us. (Those dark beers have all the heart-healthy benefits of wine, which Calvin needs because our insurance won’t pay for cholesterol meds though they will pay for heart attack care. The meds seem cheaper to me, but hey, I’m not an insurance executive. The dark beers are good for me because they are about the only thing besides heavy-duty meds that prevent bone loss, a risk for me because I have tiny bones.) Anyway, back to brewing. I brewed, chilled, and poured the wort into the primary fermenter. (Wort is the beer base consisting of water in which various grains have steeped, boiled malts, hops, Irish moss, etc.)
Then, I pitched the yeast. Cal and I have different opinions on yeast. I like the dried yeast—it takes longer to get going, but it’s reliable. Cal likes the pitchable active yeast because it’s faster and more authentic. It is also HUGELY unreliable. In other words, when you pitch 1 billion live yeast cultures into 5 gallons of malty delight, they go crazy. I pitched the yeast and only muttered slightly under my breath. I put in the air lock. For those of you who aren’t familiar with the chemistry of yeast, here’s a primer. Just like bread yeast, brewer’s yeast digests the sugars and releases carbon dioxide and alcohol. (That wonderful smell of baking bread is a combination of ozone and alcohol—but with bread the alcohol evaporates.) The air lock in the fermenter allows the carbon dioxide to escape while preventing the beer from being contaminated with wild yeast. There’s yeast all around us in this wide world.
Of course, 1 billion active yeast cultures produce a lot of carbon dioxide. Before we went to friends’ house for homemade ice cream and fireworks, we checked the beer. Everything was proceeding smoothly. The airlock was releasing the carbon dioxide properly.
We had a lovely time eating ice cream and watching the fireworks. Then, we went home. The children were the first ones in the kitchen. I heard “OH. Wow.”
Needless to say, 1 Billion live yeast cultures release A LOT of carbon dioxide, enough to easily overwhelm an airlock. My first mistake was inserting the air lock tightly into the primary fermenter. If it hadn’t been in quite so tightly, the CO2 would have just blown out the air lock. But, it didn’t. Instead, the pressure built and built...until the lid blew off the fermenter. Imagine trub (the fancy word for yeast by-products, which really ought to be called “yeast scum”) all over the floor, the cabinets, the WHITE curtains, the counters, the stove, and the ceiling. Yep, if it hadn’t been so funny, I might have been frustrated. But trub on the ceiling really is funny.
Cal helped me clean up and then moved the fermenter to the laundry room. Later, just before we went to bed, I decided to check the fermenter one last time. The lid, which is supposed to be convcave, was convex. I decided to release the pressure by wiggling out the air lock. Let’s just say that 1 billion live yeast cultures' by-products pouring out of a small opening travel with great force. I got a faceful of trub. I suppose if I owned a salon I could charge lots of money for yeast-extract facials (read “a faceful of yeast scum”), but I don’t. So, I washed it off and went to bed.