Tuesday, October 30, 2007

Brew day: Doppelbock? Schwarzbock? Imperial Schwarzbier?

Okay, so Sunday was a brew day, and Leah and I were planning on taking our first shot at a Doppelbock for our Christmas beer. With 20 lb. of malt and a target O.G. of 1085, it was by far the biggest beer we have planned (especially all-grain). While things didn't go totally as planned, I think I'm starting to get a better handle on all-grain brewing and I consider it progress. Here's the recap:

First, I decided to follow Dave Miller's suggestion and pre-heat the mash tun. Based on the resulting mash temp, I don't plan on doing it again. Between letting the strike water sit for twenty minutes and re-heating it to the mash temp, it probably added a good 45 minutes to the brew day.

I mashed in (1.25 qt./lb.) at 1pm at 171°F with a target mash temp of 158°F. Based on past experience I would've gone with 175°F (the suggested temp from the Green Bay Rackers website) but since I pre-heated the mash tun I decided to go with the ProMash strike temp, which has generally been too low for me. Turns out to be a bad idea as the mash ended up at 152°F. After 15 minutes the pH was at 5.1 so that was looking good. However, at thirty, when I stirred the mash, the temp was down to 148°F. I added some boiling water, but I didn't have much to add so it only brought it back to 152°F. Naturally I'm concerned that the beer won't have sufficient body, but what are you going to do?

During the mash rest, I heated up around seven gallons of sparge water to 168°F. The pH was at 7.1, so I added 1/2 tsp. acid blend. That only brought the pH down to 6-something so I added another 1/2 tsp. I forgot that pH was logarithmic, and I ended up bringing the pH down to 4.4. Oops. I can't find anything that says what happens when you sparge with water that's too acidic, but that may have contributed to the low efficiency that I achieved yet again.

At 2:08pm I started to recirculate. At 2:25 I started to collect the first runnings. I measured a gravity reading of 1072, which is a bit low (if I am to believe my fellow homebrewers at BeerAdvocate) but it's possible that the overly acidic sparge water was part of the problem. Also my sparge water cooled down to 162°F by the time I sparged (something to keep in mind next time).

I began to sparge at 2:35 and by 2:55 I had run off 3 gallons. I started the burner on the boil kettle as soon as I started sparging to carmelize the first runnings. The wort was at 1056. At 3:10 I had collected 4.5 gallons at 1041. By 3:20 the sparge water ran out. At 3:25 I had collected 6.5 gallons and the runoff was at 1030. At 3:40 I stopped sparging as I had collected what I thought was 8 gallons. Unfortunately, I was using a new keggle which required me adjusting my calibration sheet from the old keggle, and I think I screwed something up at some point because as I started the boil I realized I had actually collected close to 9 gallons. Obviously this makes it a little difficult to figure out what my sparge rate was, and this was something I really wanted to keep track of this time. D'oh.

I boiled from 3:40 to 6:25, boiling down from 9 gallons to 6 (I would've kept boiling down to 5.5, but we had company as of 5pm and I hadn't planned on being out there so long in the first place). My gravity reading at the end of the sparge was 1045, which would boil down to 1072 at 5.5 gallons. As it was, I boiled down to 6 gallons and ended up with a gravity of 1065.

Given the low O.G. and the low mash temp, I'm thinking this might come out too thin to be a Doppelbock. Given the generous amounts of Carafa I malt that I used, it's very dark so I'm thinking it might be considered a Schwarzbock. However, the low mash temps may make it too thin to be classified any kind of Bock, so perhaps Imperial Schwarzbier will be most appropriate. I suppose I won't know for sure until I try it.

In the meantime, I pitched at 70°F with the yeast cake from a 2L starter of WLP833 German Bock Lager yeast. I put the carboy into my chest freezer set at 55°F and fermentation had started by the next morning. Today I dropped the temperature in the freezer down to 50°F. Now I'll just have to wait and see how everything turns out!

So, in the end, it was a long day with some minor issues but things I can learn from. Mainly, I'm going to go with the Green Bay Rackers mash calculation plus 2°F for my strike temp and I'm going to go with 173°F for my sparge temp, figuring it will drop to 168°F by the time I actually sparge. I'm also going to add 3/4 tsp. acid blend per 7 gallons sparge water and see if that hits my desired pH range. In the meantime, we'll soon be off to Germany to visit Leipzig, Bamberg and Düsseldorf. Ja woll! I'll be posting pictures and brewery reviews when I get back. Auf wiedersehen!

Saturday, October 27, 2007

Brew day checklist

The following is a cheat sheet for tomorrow's brew day (and, if all goes well, future brew days as well):

1. Add hot water after cleaning mash tun and leave closed until ready to mash in.
2. Make sure to cover mash tun manifold with water before adding grain.
3. After mash-in, after mash has stood undisturbed for five minutes, check pH. Should be at range of 5.2-5.6.
4. Check mash temp. every 15 minutes. Stir mash at 30 minutes.
5. Before sparging, make sure pH is in range of 5.2-5.6 (for Chicago water, add 1/4 tsp. acid blend per 4 gallons sparge water).
6. For recirculation, run off 0.5 qt/min. Should take around 15 min.
7. For run-off, reduce rate to ~0.33 qt./min. Start sparge when water gets to 1-2 inches above grain bed. Should take 10-20 min.
8. Begin sparge; slowly increase rate of run-off to .5-.6 qt./min. Should take around an hour.
9. Don't let run-off drop below gravity of 1010; also avoid a pH of above 7 (adjust sparge water pH if necessary).

Okay, that should be good for now. Just some guidelines to keep in mind for the whole all-grain process. For anybody else reading this, I would recommend checking out this site instead of relying on these notes, as these are just things that I'm likely to forget or overlook.

Wednesday, October 24, 2007

Next up: Humbug Alleviator [?] Doppelbock

Our next beer--which will be our Christmas beer--is going to be a Doppelbock. Traditionally, the names of Doppelbocks end in "-ator" (e.g. Salvator and Optimator), so I'm trying to come up with a name that's related to Christmas, weather, or ideally both. Right now the leading name choice is "Humbug Alleviator," though other options are "Arctic Precipitator," "Red-Nosed Navigator," "St. Nick Impersonator," and my personal favorite, "Snowed-in Fornicator" (think blizzard babies are a myth? check it out: http://abclocal.go.com/wls/story?section=local&id=5680050). Feel free to contribute other suggestions.

Anyway, I made the starter last night after some thermometer issues. I'm making a 2-liter starter for a 5-gallon batch, and after pitching around 11pm last night I saw signs of fermentation when I woke up this morning. Tentative brew day is Sunday.

Tuesday, October 16, 2007

Altbier update

I kegged the Altbier on Sunday. The good news is it seems to have attenuated well (down to 1011, just a hair below my target FG) and there don't seem to be any off-flavors. The bad news is, upon tasting it, I realized that I never scaled down my bittering hops from the original 5 gallon recipe to the 3.5 gallons I actually yielded. The result? One bitter Altbier. I'm talking citrusy, IPA-level bitter (despite the fact that I used Northern Brewer hops for bittering and not some Northwest U.S. grapefruity hop). It's a must-drink for any hophead out there. Too bad I'm not really a hophead myself, but it's definitely interesting. And, while it's not what I was going for, it's a unique and drinkable mistake, which is part of the fun of homebrewing. I still think next time I might go for a little more malt, but it's hard to say with all those hops! I think it will be interesting to see if the bitterness mellows at all with the cold conditioning and carbonating. My experience has been that the flavor/aroma hops are more likely to subdue than the overall bitterness, but oh well.

Wednesday, October 03, 2007

Brew day - F5 Altbier (take two)

So this is my first post in a while. It's not that I haven't brewed in the last couple months, it's just that I've been brewing for parties. That means quick, tried-and-true mini-mash recipes which are fairly routine and not worth blogging about unless something goes drastically wrong. Thankfully, nothing did.

Anyway, after the last Altbier fiasco (see the last two posts), I decided to give the Altbier another shot this past Sunday. I also decided to just go with a 5-gallon batch this time, to eliminate some issues from the last time (mainly cooling, as it was 80°+ on the brew day). Unfortunately, it was another day with several issues (why can't my all-grain brew days go as smoothly as my partial-mash ones???), but we'll see how it all ends up. For now, here's a recap...

I mashed in at 168°F with a target temp of 152°F. Yeah, I know that's high, but my tun (a converted Rubbermaid cooler) doesn't seem to retain heat very well, so I'm more concerned about being too low than too high. One frustrating thing is, with the Gott-style coolers (that is, the cylindrical ones), I would think you would have a significant vertical temperature profile within the tun, so I don't think taking a temperature reading at the top of the tun is going to give you a good idea of the mash temp at the end of the mash. As such, I have no idea where my mash is finishing. I suppose I could stir the mash during the rest, as it will settle while recirculating, but for some reason that didn't occur to me until now. Mental note for next brew day. Anyway, I mashed for an hour and then recirculated for about fifteen minutes. It cleared up pretty quickly. I then sparged with 168°F water for about 45 minutes. Everything seemed to go well until I ran out of sparge water and I only had about four gallons of wort. I tried tipping the mash tun slightly but that didn't do anything. I decided to roll with it, figuring I had already extracted most of the sugars and could always add some water to bring the volume up.

As the wort was heating up, I took a gravity measurement. 1020 without the temperature correction; 1032 with a temperature correction, which estimated at a 1042 original gravity after accounting for evaporation during the boil. Dammit, I was pissed. How could my gravity be that low AND my yield be so low? Well, I figured I would again roll with it, rather than add some dry malt extract to bring the gravity up. I added my initial hops (Northern Brewer with a little bit of Spalt for logistical reasons) at the beginning of the boil, adjusting for a 3.5 gallon batch (since the recipe was obviously for five gallons). At fifteen minutes I added my immersion chiller and Irish moss. Then, when I was about ready to add the final hops, I realized I forgot the addition at 15 minutes. So I added half of what was left of my Spalt bag (roughly .3 oz), let it boil for ten more minutes, and added the final .3 oz at knock-out.

I chilled to around 70°F, racked to a carboy (with an estimated yield of--yikes--three gallons) and took a final gravity reading. 1052, only two points off from my target gravity. Of course, if you get that extraction for a 5-gallon yield, your gravity would be 1032. But at the same time, it's way better than the 1032 I estimated for 3.5 gallons. I attribute this error to a combination of two things: 1.) the inaccuracy of taking a gravity reading at 135°F, and 2.) while some have told me otherwise, I believe that the denser wort settles to the bottom of the brew kettle, so even though I stirred it well before taking my sample, my sample was drawn from the top which had a lower gravity (being a late running). Next time I'm thinking I should take gravity readings during the run-off to get a better idea of my runnings. Plus, had I done so this time, I could at least estimated what my yield would have been had I not run out of sparge water. (For the record, when I dumped out the grains, there didn't seem to be an excess of water so I suspect somehow measured my sparge water incorrectly).

Just for fun, I'm going to do some back-of-the-envelope calculation of what my gravity would have been had I not run out of sparge water. Let's start by assuming that gravity decreases linearly (which it obviously doesn't, due to the law of diminishing returns). Next, since my gravity reading after the sparge was 1032, and I had done some mixing, let's estimate the gravity of that final run-off was 1020. Now I've heard that it's supposedly not worth sparging below a gravity of around 1006, so let's assume that's what the gravity would have been at the end of the sparge. Since the average of 1020 and 1006 is 1013, we'll assume that would be the gravity of the final 2.5 gallons we should've extracted. That's approx. 33 additional gravity points we would have gotten. That gives us a final gravity of 1043 for a five-gallon batch. That would be 62% brewhouse efficiency, which still isn't great. Of course, there are a lot of faulty assumptions there, so who knows what it really would have been. Regardless, I'm concerned about my efficiency. I currently don't use a sparge arm; I'm thinking of making one and seeing if that helps.

Anyway, once I pitched the carboy went straight into the fermenter set at 65°F. Last time I fermented way too hot and bad things happened (especially since I'm using the White Labs Alt/Kölsch yeast, which doesn't like high temperatures). Of course, since I didn't make a starter, the cooler temp meant we didn't get fermentation until around 60 hours after pitching. I hope that doesn't cause any problems, though I guess time will tell.

Oh, and one other thing went wrong. When I was putting stuff away, I found an extra bag of Spalt hops. That's when I realized that it wasn't just the one remaining bag of hops that was supposed to go into the kettle; there was a whole 'nother bag as well. Fortunately, I'd rather add too little flavor/aroma hops than bittering hops, and if it needs more aroma I can always dry-hop (which will also give an illusion of more flavor). But we'll cross that bridge when we get there. In the meantime, I'm just glad that we have fermentation and we'll see what happens from here on out. Cross your fingers!