Wednesday, May 13, 2009

Old Dominion Brew Day

The two of us escaped work early and arrived at Old Dominion Brewing Company on a beautiful sunny March afternoon for a day of brewing Old Dominion Pale Ale with Tim Pohlhaus, who is not only one of the brewers but also a good friend of ours. Tim is a brilliant guy with a doctorate in Biochemistry who has completely dedicated himself to brewing.

Founded in 1989, ODBC was recently acquired by Coastal Brewing Company, who operate a second brewing operation (Fordham) in Dover, DE, and who made the tough decision to close the brewery in Ashburn and consolidate brewing in Dover. We both respect the quality and range of ODBC beers and it was sad to hear one of our local breweries was leaving town. It was nice to have the opportunity to do a brew day with Tim before the shutdown, and see the old brewery off in style.

The brewery is located in an industrial park in Ashburn, Virginia, about an hour outside of Washington, DC. Around the front of the building there used to be a brewpub where they had many of the ODBC beers as well as occasional test batches on tap, but it was shuttered a few months back.

The big silos out back contain the base malts.

Mike helped out at Milly's Tavern a couple times and found the general flow of the day to be very similar to homebrewing (you mill, mash, sparge, boil, chill, pitch). The steps were all the same at ODBC, but in this production environment there are always a couple of batches at different points in the process. So for example while one batch is mashing another is boiling. This is a more efficient use of the brewer's time, and allows a smaller system to be used to produce more wort (often four 25 barrel batches are combined into one 100 barrel fermenter). Production brewing on this scale also demands strict organization and complete attention, as you are trying to brew all these different batches at the same time, with multiple clocks running on different tasks. I have no idea how Tim was able to have an engaged conversation, train us on the system and have multiple batches going at the same time.

The brew starts out with milling the grist. The base malt is brought over from the silos by an auger. The desired weight is punched into a control panel and the auger stops when that weight is hit. Next we load a pallet with the bags of specialty malt, Tim hops in the forklift and hefts the pallet up to the top of the mill where we can rip them open and add them by hand. All the while we're wondering if Tim is the sole biochemist-brewer-expert-forklift-operator on the planet.

A second auger brings the milled grain over to the mash tun where it is mixed with hot water from the hot liquor tank.

The hot liquor tank holds the mash and sparge water. This is mixed with cold water by manually opening and closing valves to achieve the desired water temperature.

No stirring the mash by hand for the brewers. The mash agitator spins around mixing the grain and hot water. The same equipment is used to clean the grain out of the mash tun after the boil is finished (an auger at the bottom of the mash tun takes the grain to a storage bin where a local farmer comes to pick up the grain to feed to his livestock).

Below is the lauter tun, and the mechanisms being controlled are the lauter rakes. They help if the bed needs to be cut. Another arm is lowered when it is time to grain-out. The mash vessel is a separate entity.

After the mash and sparge, the rather impressive boil takes place. With the air flow directed up the vent at the top of the kettle, very little steam or aroma makes it from the boil into the rest of the brewery.

Tim took samples at many different points in the process to check the gravity and pH. They have a pretty cool chiller for their samples, when the handle is turned water flows through the PVC around the copper tube which holds the sample.

We made several timed hop additions during the boil and yes, it was as fun as it looks tossing huge quantities of hops into a beer.

To see how much wort was left they have a PVC rod that is calibrated to hang off the lip of the brew kettle. This is pretty similar to the way we take volume readings at home (smaller sticks of course).

During a lull in the action, while the boil was going, Tim pulled us a few samples, including the lightly funky Oak Barrel Millennium and the freshly dry hopped Beach House Golden Pilsner. The amount of experimentation involved in the Oak Barrel Millennium project made it one of the more ambitious projects that ODBC has ever done. We're both gonzo about wild fermentations and we were lucky enough to taste many of the evolutions of the project beers in the course of the last year thanks to Tim.

At the end of the boil the wort is drained out of the kettle leaving some of the hops behind.

On its way to the fermenter any hops that make it into the line are filtered out before they make it to the fermenter.

Other than brew beer, Tim also does most of the lab work for ODBC. The lab is second nature to him and on this night he had to do some cell counts so there would be yeast ready to go for the next set of brews. He also checked some samples he had plated and incubated to check for beer spoilage microbes (they were all clean).

First he weighed out a sample of the yeast slurry, I believe it was 20 grams.

Then he diluted the yeast slurry in 5L of water, agitating with a stir plate for a few minutes to get an even distribution of yeast cells.

After putting a sample onto a slide using a pipette he used a microscope to take an accurate cell count, the dead cells are stained blue by Methylene blue.

Our last task was to stop into the cold room and measure out the hop additions for the next brewer's shift (Tim still had a few more hours to go on his 12 hour shift). The cold room is a real wonderland, a large walk in refrigerator where special one-off kegs and hundreds of pounds of boxed hops are stored. We measured out five mixed hop additions for four batches. When you slice open one of the large sealed hop bags, the aroma is like beer geek heaven.

An altogether great day of brewing with a good friend and awesome brewer. This is a different experience than what we are likely to have in every other brewery we visit: but a last hurrah at our local brewery seemed like the best place to start our journey.

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