Weizenbock missed gravity

First things first...recipe.

5 gallon


8.5# wheat
4.25# Munich I
2.25# Pils
.25# chocolate
About 1/3# DME leftover from my started thrown in for good measure.

Intended OG: 1.082
Real OG (temp corrected from hot wort): 1.056

Basically I hit all my temperatures, but my gravity was way off. I was going for 70% efficiency and a final of around 8% (close to the Aventinus numbers I saw when doing research). I very well just could leave this and be well within the ranges and color for a dunkelweizen, but I would really like this to be a bigger beer to be ready for cool fall nights.

I was wondering what dumping around 2 pounds of sugar would do to this? I haven't pitched the yeast yet, and I know there have been some spectacular accidents (pliny, brown shugga, ect) when missing the OG and using sugar. Is 2.25 pounds of table sugar too much? Too little?

If you used flaked wheat you may not have had enough diastatic power to fully convert the malt.

Flaked wheat= 0 degrees Lintner
Munich I= 50 dL
Pilsen= 130 dL
Chocolate= 0 dL

So if you do a weighted average:

(0*8.5Lbs Wheat + 50*5.25Lbs Munich + 130*2.25Lbs Pilsen + 0*.25Lbs Chocolate)/15.25Lbs Total Grist Weight = 36.4 dL/Lb

The minimum average for conversion is around 50 dL or so, but it's a good idea to get higher than that to be on the safe side. There's a good article about diastatic power on BeerSmith's Blog Site here

The other possibility could be that not enough sugar got rinsed in the sparge with all of that wheat in the grain bill. Maybe try adding 1/2Lb of rice hulls the next time you brew the recipe to see if it loosens things up and improves efficiency.

Instead of the sugar I'd be more inclined to add 1-2lbs of wheat DME to spike it, dissolved in about 1-2 qts of hot, sterile water. That much sugar may add more funk than you would like and would dry it out quite a bit.