First All Grain Done- Have some ?

[nediver]

So I have some questions after my first All Grain Brew. I am using Beirmuchers SWMBO Slayer recipe. I had no idea what my brewhouse efficiency was so I left it at 75%, but added 1# of DME. I also wanted a higher alcohol % then the original. Here is the grain bill, etc.

SWMBO SLAYER
Simple single infusion mash for use with most modern well modified grains (about 95% of the
time).
Brew Type: All Grain Date: 12/24/2010
Style: Belgian Blond Ale Brewer: ANDREW
Batch Size: 5.25 gal Assistant Brewer:
Boil Volume: 6.50 gal Boil Time: 60 min
Brewhouse Efficiency: 75.0 % Equipment: Brew Pot (7.5 gal) and Cooler (48 qt)
Actual Efficiency: 2.3 %

Ingredients
Amount Item Type % or IBU
1.00 lb Light Dry Extract (8.0 SRM) Dry Extract 8.9 %
4.99 lb Pale Malt (2 Row) US (2.0 SRM) Grain 44.4 %
3.99 lb White Wheat Malt (2.4 SRM) Grain 35.6 %
0.50 lb Caramel/Crystal Malt - 10L (10.0 SRM) Grain 4.4 %
0.50 lb Wheat, Flaked (1.6 SRM) Grain 4.4 %
0.25 lb Munich Malt - 20L (20.0 SRM) Grain 2.2 %
1.00 oz Williamette [5.50%] (60 min) Hops 17.9 IBU
1 Pkgs Belgian Witbier (Wyeast Labs #3944) Yeast-Wheat
Beer Profile

Estimated Original Gravity: 1.063 SG (1.062-1.075
SG)
Estimated Final Gravity: 1.016 SG (1.008-1.016 SG)

Estimated Alcohol by Volume: 6.2 % (6.0-7.5 %) Actual Alcohol by Volume: 0.6 %


So my readings were as follows:

I hit all my target volume pre-boil and post.

Pre Boil Gravity was taken at a high temp, after mash out I added the DME to the kettle, stirred in and took a reading. Adjusted it for temp in BeerSmith (forgot to note temp but prob close to 180 deg).

Post Boil Gravity was taken at 60 deg.

Pre-Boil= 1.053
Post-Boil= 1.052

According to recipe it should have been 1.051 and 1.063 respectively

My interest is in getting my brewhouse efficiency dialed in and consistent. So here goes.

If the total ptnts available for this recipe is 84 than at 75% eff your looking at an OG of 63.

If I measured an OG of 52 than 84/52 gives me a brewhouse efficiency of 61%. Probably right on target for my first All Grain with a single Batch Sparging.

Obviously I was upset because I was hitting all my volumes and temps, and my pre-boil seemed spot on. I expected it to go up after I boiled off a gallon of liquid, but it seems it was an inaccurate reading.

The cooled Hydro sample tasted awesome by the way.











(batch_pts) = (potential_pts) * (brewhouse efficiency)

(efficiency) = (measured_pts) / (potential_pts)

(efficiency) = (measured_pts * target_vol) / (potential_pts * actual_vol)

 

[mkirkland]

The pre-boil reading was the first thing that struck me as odd. If you are boiling off liquid then that pre-boil OG reading must have been wrong. 61% sounds pretty good for a first time AG batch with a single batch sparge.

 

[Bobby_M]

It's very possible that the preboil sample wasn't fully homogeneous. The first runnings and sparge runoff could have been stratified and you took a sample from the lower gravity. Also, I wouldn't recommend dropping a hydrometer into 180F wort. You could shock/crack it.