One of my favorite styles of beer is the Belgian Golden Strong, and the classic commercial example is Duvel. When operating the brewery in San Miguel, I always tried to have this beer in the rotation, and as delicious as this beer is, the ingredients are as simple as you can get.
Pilsner malt and refined sugar.
You could complicate it if you want to by producing some inverted sugar to replace the refined white sugar, but I haven't found it to improve the beer, and I like to keep things simple if the results are good. The best yeast I've found over the years that comes the closest to mimicking that unique flavor of Duvel is White Labs WLP545 yeast, and I won't brew this beer if I don't have any to pitch.
Now, as simple as I like to keep this recipe, I was forced to use some acidulated malt in my latest batch in order to drop the mash pH to 5.3.
One other caveat: I didn't get the efficiency from my mash that I calculated the recipe based on. I was expecting to be in the low 80%, but ended up with 78% and was forced to add some additional sugar to make my preferred original gravity. Then, rather than do math, I just dumped in 2.2 pounds of sugar when in fact I only needed 1 pound. Soooo... my O.G. came in at 1.079 instead of the 1.074 that I was shooting for. Sooo... the alcohol came in higher. If I'm not mistaken, Duvel is 8.5% ABV, and this beer came in at 9.3% ABV. Not quite as drinkable at that higher percentage, but it will still be a crowd-pleaser for those that like their Belgians boozy.
The following is my recipe as intended, and I've included the discrepancies in parenthesis for your reference.
Recipe:
I brewed an 11 gal. post boil batch anticipating 2 full 5 gallon kegs after fermentation. I referenced Bru'n water yellow bitter water profile and used 100% reverse osmosis water.
Efficiency 84% (actual 78%), Attenuation 87% (actual 92%), ABV 8.5% (actual 9.3), SRM 4.5, IBU 35, OG 1.074 (actual 1.079), FG 1.008, PH 5.3
23 lbs. Pilsner malt (Weyermann)
.75 lbs. Acid malt
4.4 lbs. or 2 kilos (actual 3 kilos) refined sugar at start of boil
Mash in at 152f. in 6 gal. h2o for 60 minutes.
Sparge with 10 gal. for 45 minutes with 170f. h2o
Boil 90 minutes with:
60 min. add: 65 gram Warrior 13% a/a est. 34 ibu's
20 min. add: 20 gram Tettnang 2.1 a/a% for est. 1 ibu's
Chilled down to 68f., transfer to fermenter and pitched 3 pkgs WLP545 yeast.
After 3 days raised temperature to 72f.
After 3 more days raised temp. to 75f.
After 3 more days lowered temp. to 62f. for 1 day.
Transfer to kegs and lagered in kegerator for 2 weeks at 40f.
Lessons learned - Add sugar to achieve gravity a little at a time if needed, checking gravity as I make the additions.
Cheers!