Alt Roundup, 2nd Edition
January's style talk is on alt beer, or altbier. 
This is the style of the Broken Hydrometer Invitational.
You have just enough time if you get going now. The styles: Alt is German for old. 
What is meant in this case is that the beer is made in the old, or ale, style. 
In fact, the beer is usually considered to be one of the hybrid ale/lager styles 
(cream ale, steam, and Kolsch are the others). This is because it receives a cold 
conditioning akin to a lager, after its relatively warm fermentation. 
The style is a bit of a mystery for most people for several reasons. First, 
there aren't very many alt beers. What ones do exist actually fall into as many as 
five different substyles. And the "best" substyles, Düesseldorfer and Sticke, 
are essentially impossible to get in the US.
Note, the names given to the substyles are somewhat arbitrary. 
In many cases there are other names used but these are what I have seen commonly.

Düesseldorfer Altbier
AHA/BJCP description:
8B. Duesseldorf Altbier 
Aroma: Munich malt aroma, with a restrained fruitiness. Hop aroma may vary from 
low to moderate. Appearance: Orange-copper to brown color, with brilliant clarity. 
Thick, persistent head. Flavor: Assertively bitter, with intense Munich malt-derived 
flavor to support. Fruity esters should be restrained; 
some chocolatey notes are often present. Hop flavor should be low to medium. 
Mouthfeel: Medium-bodied, with moderate carbonation. 
Some commercial examples have a dry finish resulting from a combination of high 
bitterness, higher attenuation, and moderate sulfate in the water. 
Overall Impression: Bitterness is very high, especially in relation to
the (moderate) gravity. Munich malt character lends balance, resulting in a 
bittersweet character. Very smooth from fermentation at the lower end of the 
temperature range for ales, followed by a period of lagering. 
History/Comments: A very bitter beer with a pronounced Munich malt character. 
Ingredients, fermentation at low temperature (for an ale), and a lagering period 
combine to lend a cleaner palate than for most ales. 
Predates the isolation of bottom fermenting yeast strains, though it approximates 
many characteristics of lager beers. Many Northern German Altbiers are lagers. 
Ingredients: German Munich malt is essential to obtaining the necessary depth of malt 
character. Hops are traditionally Spalt, though other German varieties are often used. 
Vital Statistics: 
OG: 1.040-1.055 
IBUs: 40-60 
FG: 1.012- 1.019 
SRM: 11-19 
ABV: 5-5.5% 
Commercial Examples: Zum Uerige, Zum Schluessel, Im Fuchschen, Widmer Ur-Alt, Schumacher. 

The classic example is considered to be Zum Uerige (55 IBU's). Others are 
Im Füchschen and Zum Schüssel. The Widmer version is only sold in Portland. 
Don't confuse this with their other beer labeled Alt (see below).

Sticke
Sticke alt is a special alt made by the breweries that make the Düesseldorfer alts. 
It is a stronger, more bitter (as much as 65 IBU's!) version and is sometimes dry-hopped.

Northern German or "Dortmund" Altbier
AHA/BJCP description:
8C. Northern German Altbier 
Aroma: Little aroma; malt should dominate to the extent that any aroma is discernible. 
Appearance: Copper to brown color; very clear. Good head retention. 
Flavor: Assertively bitter yet balanced. Munich malt-derived flavor, 
along with a chocolate-like malt aspect, supports the bitterness. Esters are restrained, 
and hop flavor should be low to medium. Mouthfeel: Medium body, with an 
overall balanced impression. Overall Impression: A very clean and relatively bitter beer, 
balanced by Munich malt character. Less intense than the Duesseldorf version of Altbier. 
Comments: Most Altbiers produced outside of Duesseldorf are of the Northern German style. 
Many are simply moderately bitter brown lagers. 
Ingredients: Typically made with a Pils base and colored with roasted malt or some 
dark color syrup. May include Munich malt. Hops are traditionally Spalt, though other 
German varieties may be substituted. 
Vital Statistics: 
OG: 1.040-1.055
IBUs: 25-40 
FG: 1.012-1.019
SRM: 11-19 
ABV: 5-5.5% 
Commercial Examples: DAB Dark, Diebels Alt, Alaskan Amber, Grolsch Autumn Amber.

These are the common alt in Germany. Many of the larger breweries make a beer in this style. 
They are really just dark lagers, without the fruitiness or high bitterness 
found in the Düesseldorfer alts. Examples of this style include DAB dark (32 IBU's), 
Schlösser (32) Hannen, (28), Weihenstephan (27), Diebels (32). 
Note that some of these are made in or around Düesseldorf but don't fit that style.

Pinkus Müller Münster Alt
This beer is unique. With only 18 IBUs, this beer is made with 40% wheat malt, OG of 1.045, 
is top fermented and then cool conditioned for 6 months with a lactic acid bacterium. 
The wheat leaves it pale and cloudy, the bacteria, sour. 
This beer can be found at good beer stores around here.

American Alt
The last "style" is the American alt. These vary but in general are sweeter than any of 
the German versions and lack the bitterness of the Düesseldorfer alts. Schmaltz Alt from 
the New Ulm brewery is one example. St. Stan's makes another ("Amber") which I have 
found to smell of camphor! Widmer and Alaska Brewing Company are other makers.
Making a Düesseldorfer alt:

Fermentation temperature and yeast are probably quite important to getting this just right. 
The WYeast alt yeast (1007) reportedly doesn't have the right character and the BrewTek 
yeast produces a lot of phenol and fusels (probably the yeast from St. Stan's). WYeast 1338 
is worth a try. I like the Head Start alt yeast, which is currently not available. Also the 
American Hefeweizen yeast from various yeast suppliers or Widmer Hefeweizen 
is reportedly the Zum Uerige yeast.

Here is a recipe I put together after some research. I made it a few times with the alt 
yeast from Head Start. Never having had the real thing I'm not sure how accurate mine was 
to style, but I thought it had too much lager character, 
sulfur in particular. Russ Pencin, who has had the real thing, 
indicated it was a good attempt.

For 12 gallons:

14 oz DeWolf-Cosyns CaraVienna 
14 oz DWC CaraMunich 
14 oz DWC Aromatic 
1.5 lbs Munich 
5 oz Belgian Chocolate (Black?) 
DWC Pils malt for an OG of 1.053

Low AA hop added at 60 minutes for 55 IBU's. Spalt preferred, tettenanger or saaz OK. 

Ferment at 60-65ºF 4-7 days, 
then drop to 40ºF at 3-4ºF/day for a total of 3-4 weeks at lower 
temperature (including the ramp). 

Al Korzonas's Altbier (it's had many names, always with the initials ZU ;^)

8# Weyermann Dark Munich or DeWolf-Cosyns Munich
1# Weyermann Melanoidin malt or DeWolf-Cosyns Aromatic
3 oz. Spalt pellet hops (~4.7% AA) boiled 90 minutes
Wyeast #1338 European Ale yeast

Mash for 1 hour at 156F.
Boil for 90 minutes.
Cool, oxygenate, pitch a 2L starter.
Ferment at 63F until done.

I've found that there is little difference from lagering this beer.

OG: 1.050-1.053
FG: 1.011-1.012

Charley Burns' MCAB Dusseldorf Altbier - First Place Recipe

Starting Gravity : 1.056
Ending Gravity : 1.017
Volume: 11 Gallons

Malt
0.25 lb. Black Patent=20
1.00 lb. Crystal 60L -Hugh Baird=20
15.00 lb. DWC Munich=20
5.00 lb. Halcyon Pale Ale=20
1.00 lb. Malted Wheat=20

Hops (all whole):
2.00 oz. Tettnanger 4.4% 60 min
2.00 oz. Hallatauer-Northern Brewer 9.4% 60 min
1.00 oz. Tettnanger 4.4% 30 min

Notes:
Single Infusion Mash Temperature: 156F
Wyeast 2565 (kolsch) 1 quart starter
3.5 months lager @ 33F