Sunday, October 4, 2009

New tun, new water, new yeast, new hops, new volume = new beer?

There's a commonly-held belief that you should only change one thing at a time while troubleshooting a problem. My philosophy is more like "let's change things and see how it breaks differently." Saturday's brewing session exemplified that quite well.

Brewed: 091001 Geordie-Boy Ale

Can I even call this Geordie-Boy with all these changes? On the ingredient side, I used all the right grains, but the grind on the 4 ounces of chocolate malt was a little fine - I have it uncrushed, and I used my coffee mill. (Actually, "a little fine" is an understatement - a lot of it was powder. Wonder what that will break?)

I was going to try for the original recipe's hop schedule as well. The IBUs on the finished beer have been a little light because I didn't scale the East Kent Goldings I was using for bittering to take into account the difference in alpha acid percentage between EKG and Target, which is what the recipe actually calls for. I set out to use Target for the bittering, but Alabrew didn't have any so I got Galena instead. It has the same alpha acid percentage (11%) as Target. I used East Kent Goldings as usual for the flavor and aroma addition.

I used different yeast too. Since I don't have any Wyeast 1099 (Whitbread Ale) which is what I had been using, I switched to White Labs WLP005 British Ale yeast. It's the first time I have actually used a White Labs vial. I have two Irish Ale vials that are now expired, from my plan to brew a Guinness recipe that never made it into the pipeline because I didn't invest in the nitrogen system to serve it. The yeast was easy to use (they don't call it "pitchable" for nothing). We'll see how the fermentation goes.

Process changes abounded as well, and some of them were not intentional at all.

I planned from the start to use my newly-constructed larger mash tun, and it worked out fine. I was a little concerned because the grain bed wasn't very deep, being spread over a much larger surface area, but gravity-wise it worked out. As I suspected, I was able to control the heat loss during the mash just by insulating the lid. I used bed pillows, laying them on top of the tun, and I had no measurable temperature loss over the hour of mashing. This tun was large enough to take my entire volume of sparge water at once, and my screen manifold worked just fine. The best part was the convenient rolling of the tun to the back yard to dump the spent grains.

About that water: I constructed a filtering system to provide filtered tap water for brewing instead of using it straight from the Pelham Waterworks. I got a Omni U25 whole-house filter at Walmart. It is intended to be plumbed directly into the 3/4" supply line in your home. The filter housing itself is 3/4" NPT threaded, so I got a female garden hose to 3/4 NPT male adapter for the inlet side, and an threaded hose bibb for the output side, and voila! instant on-demand filtered water in a volume and delivery format I can actually use. I hooked it up to the hose system I was using, drew the mash and sparge water volumes, and disconnected it to store for the next brewing session.

Of course, filtering the water's not much use when you boil it away. Somehow during the boil session I let the boil-off rate get out of control and I ended up with a post-boil volume of 4.6 gallons. I'm not really sure how that happened, to be honest. I actually started with more wort than the batch sheet called for and had to boil some down to the right amount before starting the "timed" 90 minute boil. I flamed out right at 90 minutes and ended up a half gallon short. Guess it's time to recalibrate the boil rate. Maybe it's seasonal - it is a bit cooler now than it has been.

The original gravity for this batch came in at 1.048, which I computed as equivalent to 1.044 in 5 gallons using this great discussion on gravity in wort. The particular calculation I used to determine this is labeled as Equation 7 in that article: SG2(points) = v1/v2 * SG1(points). So in my case it was SG2(points) = 4.6/5 * 0.048 = 0.044 (you only use the fractional part of the gravity in the calculation, see the article for an explanation). That means I had 65% efficiency in the new rig, which is about what I expected.

Kegged: 090902 Por Favor

The Vienna lager-as-ale is in the keg now. It finished at 1.010, for an ABV of 5.74%. The sample tasted pretty good. I put it in the keg under 10 psi and will leave it there to carbonate the "set and forget" way. It should be ready next weekend.

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