Wednesday, July 21, 2010

On Cleaning the Boil Pot

Last Monday I had the wonderful opportunity to help brew a batch of beer at the Goose Island Brewpub here in Chicago. This was to be a collaboration brew between Goose Island and the Chicago Beer Society. The beer is a recipe by Randy Mosher for a spiced Belgian Wit called Partial Eclipse. There were a number of us helping, which basically meant we did a lot of cleaning while guys like head-brewer Jared, Randy, and Ray Daniels took care of the recipe and managing the brew process.

Anyways, of the many things I learned (and cleaned), the one that I took immediate notice of was the boil kettle - mostly because I found myself getting inside it (a tricky climb through the top port - thank you yoga!) and scrubbing while holding onto a flashlight in the other hand (very dark in there!), and trying not to hit my head/rack myself on various steel tubing. Here's me in the kettle:


The first thing that struck me was, dang - even dirty this thing is cleaner than my boil kettle! So I just set about cleaning it best I could before hosing everything down. Well, after assistant brewer Todd checked my work, he climbed in and scrubbed out a spot I missed around the drain pipe - damn! He then filled the bottom with an acid-based caustic solution, let it sit awhile, and pumped it through the plumbing. So anyways, that got me wondering....

Just How Clean Should My Kettle Be?
I posed this question to both Randy and Rodney Kibzey (Sam Adams Longshot Winner). They both recommend keeping your pots good and clean, free of both gunk and beerstone because it helps minimize any off-flavors, saves your pot from pitting, keeps the heat dispersal even, and general peace of mind. On the other hand, I've heard guys say the dirtier the pot, the better the beer - like seasoning a cask iron skillet. Post boil I've been scrubbing down with dish soap and a kitchen scrubbie-sponge, getting most, but not all, the gunk off, and then spraying the pot down with some StarSan, which is acid-based and good for the steel. I started doing this less-than-polished type of cleaning after a metallic taste appeared in one of my batches.

So the next day I decided to try properly cleaning my pot. I gave the entire thing a good 1 hour soak in PBW (1oz per gallon), scrubbing with a brush. I also opened/closed the ball valve a few quick times before and after the soak, trying to loosen any gunk in there. After an hour I gotta say the water was a gross, murky brown - and some of that gross murky brown stuff was probably getting into my boiling wort SCREW THAT! I drained it through the ball valve, hoping to flush any more crap outta there. Makes me think about investing in a 3 piece valve I can take apart and clean.

The PBW took away most everything, except there was some white stuff at the bottom that wouldn't scrub off - I took this to be some hardcore beerstone or maybe a limestone-like substance, either of which can harbor microorganisms and damage the steel underneath it. There was also some particularly stubborn, brownish beerstone along the sides still. From an article on byo.com:

Bio-fouling (trub deposits) and beerstone scale (calcium oxylate) can also cause corrosion. The metal underneath the deposit can become oxygen depleted via biological or chemical action and lose passivity, becoming pitted. A two step procedure is most effective for removing beerstone. Beerstone is a combination of protein buildup and mineral deposit, so removal works best if the protein is broken up with a caustic, like sodium hydroxide or PBW, and then the remaining lime can be dissolved by an acidic cleaner like CLR (Calcium Lime Rust Remover).

Off course you can say we're killing all those nasties during the boil, but if we're going to be clean let's be clean, and keep our kettle in good shape while we're at it. So after the PBW soak I did a splash of warm water, and an equal splash of CLR, and a sponge-wipe, and it was gone just like that. Rinse with some cold water, and wow - like new! A quick spray with some StarSan, and it's good for storage. Now my kettle is as clean as I can make it - looks good, and ready for my next batch :)

Friday, July 9, 2010

Full Length Sierra Nevada Beer Camp Entry

So I decided to enter the Sierra Nevada Beer Camp contest this year. Since I've been a drummer for 20-some years, I thought it might be cool to outfit my drum kit with various pieces of brew gear and see what sorts of sounds I could pull out of them.

So, after making my masterpiece, I got around to reading the rules - and fortunately read that the video had to be under 2 minutes long - doh! Mine was close to 5 minutes! So I had some editing to do, which didn't turn out too bad - you can see the cut version on the Beer Camp site here.

But just in case you want more - here's the raw, uncut version feature the full jam - cheers!

Matt's Uncut Video Entry for the 2010 Sierra Nevada Beer Camp Contest from Matt M. on Vimeo.

Sunday, July 4, 2010

The Other Dreaded D: DMS (Dimethyl Sulfide)

Last week we tapped our second light-colored lager, a German Pils - made with 100% pilsener malt. Our fist light-colored lager, an American Premium, suffered from diacetyl to the max (not enough yeast, no diacetyl rest). This time around I managed to get rid of the butter, but handily discovered another flavor: DMS.

At first I wasn't quite sure what I was tasting. The beer is super clear and beautiful, but yet - what is that? Unlike our previous lager, this wasn't terrible. There was just too much of something unbalancing the beer. After having a couple beer-judge friends taste it, the culprit was identified - Dimethyl Sulfide.

A small level of DMS in lagers is acceptable. In fact, now that I know what it tastes like (think corn when drinking a Schlitz), I can pick it out in other beers. Ours just has a too much of it - thankfully there's enough hop bitterness in there to cover it up some, especially when it's nice and cold. But we pitched plenty of yeast, and cooled fast by pumping ice water through our immersion chiller, so....

What Causes DMS?
The first thing each judge asked us is if we boiled with the lid on. Nope. But, I don't think I boiled hard enough to drive it all off. In an effort to save gas and avoid kettle caramelization, I've been experimenting with a less-than-rolling boil - just getting it going enough to be boiling. Well, no more wimpy boils here, now that I know that a boil isn't just to sanitize and add flavor/hops to the wort, it's also supposed to drive off stuff you don't want in there. So it's time to crank it up a bit (but not so much that hot wort is leaping out of the kettle!). In general, a 10-15% evaporation rate per hour seems to be the goal. So if you start with 7.5 gallons, you want to boil off around 1 gallon or a little more in an hour, or around 1.5 gallons for a 90 minute boil. In the meantime, I'm just going to bring the iced keg to a 4th of July party, where I'm sure it'll get sucked down pretty quick on this hot Chicago day (update: it did). Cheers!