WTF is That? – The Filter

“It looks like something you would use to hold a monster in a Guillermo del Toro film.” That’s what one member of the trivia team “Keckin’ Ass” guessed, when we asked them about the large contraption of steel that sat directly behind them during our weekly Tacos and Trivia Night in the Beer Hall.

“It might be something for boat captains to practice on?” speculated another, after noting the large wheel at one end of the object. We thought about asking what his particular field of trivia expertise was on the team, but figured it was more prudent to leave it a mystery.

The best answer we received, however, was probably the most succinct. “It squishes shit.” Exactly; and that squishiness is why we thought this medieval torture device was deserving of being the next subject in our WTF is That? series, where we highlight some of the odd, interesting, and downright unique items you can find in our brewery.

It’s called a Plate and Frame Filter, and it’s used for one of the most controversial stages in the brewing process: filtration. Controversial, because some brewers scorn filtration as an adulteration of beer, a process that “robs it of its flavor and depth.” But really, separating a beer from its sediment is just another tool we have that allows us to make creative and delicious beers. Sure, a hazy, yeasty hefeweizen would be destroyed by sending it through a filter. But on the other hand, a bright and crisp pilsner just wouldn’t be the same without this guy.

So how does it work? Well, the crux of this machine are the layers of filter medium, which force the beer through tiny holes that are big enough for liquid, but too small for yeast. The combined pressure of the liquid, the vice at the end and the layers and layers of fabric and metal, indicate that even if you start with a pretty brackish liquid, you’ll end up with something as bright as can be.

And yet, it sits in the corner of our Beer Hall unused. Why? Well, the manufacturer of the thing has gone out of business, so if any part of it breaks, we’re pretty much SOL. And there are a lot of parts – as you can see – which mean more water for sterilizing, more beer waste during filtration, more time spent setting it up, and more of a chance that something could go wrong.

 

So instead, we use these two filters right here. They operate on similar principles (with filter media inside that pick up all that yeast), but with much more control and much less swearing from the brewhouse. In the meantime, the old guy has been retired to the back of the room, spared from an entombment in the local scrapyard because, as our brewer Joe Moakley says…

“It’s really fuckin’ heavy.”