Edit: Bumpity Bump! I just realized this was from 2010, not 2011.
I'm curious about your recipe and how you decided to proceed with your DAB. I am going to brew a Dortmunder Export in another week -- I included my recipe (below) and bought some ingredients to modify my local water but have yet to decide how to proceed.
Dortmunder Export Recipe
8 lbs. German 2-row Pils
1.5 lbs. German Vienna
1.5 lbs. Dextrine Malt
0.5 lbs. German Light Munich
1.2 oz. Hallertau Hersbruck Pellets boiled 60 min.
0.50 oz. Hallertau Hersbruck Pellets boiled 15 min.
0.50 oz. Czech Saaz Pellets boiled 1 min.
Teaspoons of gypsum and calcium chloride
Yeast: White Labs WLP830 German Lager
Original Gravity 1.056
Terminal Gravity 1.013
Color 4.22 °SRM
Bitterness 26.5 IBU
Alcohol (%volume) 5.6 %
I added some gypsum and calcium chloride to the recipe to mimic the water of Dortmund. BCJP site speaks specifically to the type of water needed.
Most recipes that I looked at while I formulated this one had multi-step mashes. When malt wasn’t so well modified, it probably had a bigger effect on the beer. There are enough purists that would tell you otherwise, so…
Perform a protein rest for 30 mins @ 122° F. 60 minute saccharification rest at 152° F. Primary fermentation for 2 weeks with a diacetyl rest. Lager for a least four weeks at refrigerator temperatures. Brew on.