When I first wanted to be a brewer, I had a VERY incorrect image of what the day to day job was like. I retained this image all the way up until November 2008, when I got to brew for the first time at Tyranena in Lake Mills, WI (they have a killer bourbon aged brown ale!!!). My image was related to what I did when I was homebrewing: standing around, watching my brew bubble away, while checking the temperature every now and then, and making a mess with peanuts all over my parents garage floor. What I learned at Tyranena is that professional brewing is not standing around with a clip board watching your beer bubble away. It is 90% cleaning and 10% brewing. Sucks don't it?
Surprisingly, I realized today that one of my favorite things to do in the brewery is to clean fermenters, after we are done using them. Why you ask? Shouldn't I prefer to be standing next to the brew kettle as it boils away, smelling of malt and hops? Let me tell you first hand, this smell gets less and less exciting. What is always exciting though is the dirty fermenters! They are quite challenging to get into and when you get into them... you never know what you are going to get!
To start the fermenter cleaning, there is the yeast removal. This has to be done with the tank under pressure. There is a 2 foot thick plug of semi-solid yeast trying to get through a 2" hole on its own! Doesn't work so well. See the video below for what this process looks like... gross huh?
Often we use a hose, leading to a drain and a water spray to break apart the solid yeast "poo," so it actually goes down the drain. It comes out of the hose in this form (see video), sometimes more like diarrhea, and sometimes the hose gets a little constapated. The real attention getter of this process is when we are nearly done emptying the yeast. Now think of this... above the yeast is a 20 barrel tank pressurized to 10-12 psig with a smaller and smaller amount of yeast standing in the way. Do you see a problem here? If you aren't careful that last plug of yeast turns into a high-velocity "shit cannon" that can and will spray the wall all the way across the brewery with gooey, bubbling, yeasty goodness! The way to prevent this is the sit, crouched on the ground, next to the valve on the bottom of the fermenter cone. With your hand on the valve you can feel when gas bubbles come through. When you feel a big one, shut the valve! Simple and easy... you never know when it is going to come, you can't see or hear it, you just "feel" it through a solid pipe.
Once the yeast is out, take a few minutes to relieve the tank pressure. This sounds astonishingly like you are standing next to a jet engine if you do it fast enough. Cool huh? Then the challenging part... opening the man-way for the very first time! Unscrew the handle, pop the door inside, and do you dare peak inside??? NO! Run away! Waiting inside the tank is a wall of CO2 which will rush out, burning your eyes, nose, and lungs. Wait a few minutes until the CO2 (which is heavier than air) has a chance to leave the top of the tank, then come back for a closer inspection.
Now, finally, I can peak in the tank to see the mess left behind from our last brew. I have to spray off the door, take apart the rest of the tank, spray out the openings, and again be careful when I look inside! It is still full of CO2 in there. A warning: many breweries have lost good men who climb into fermenters too soon after opening. Make sure someone is with you if you are going to climb into one!
All that is left to do now is to hook up the CIP cart and wash the tank until its shiny and spotless!
Cheers, Prosit, and Skoal!