Trying to calculate my mash efficiency from my first all-grain batch. Using a recipe I found on-line for an Anchor Steam clone:
9.0 lbs German pils malt
1.0 lbs 40L Crystal Malt
0.5 lbs Special Roast
Mashed at 148F, batch sparged at 160F.
Calculated the expected gravity units to be 372 for 100% efficiency (used tables from Designing Great Beers by Ray Daniels), using extract potential of 1.036, 1.034, and 1.027 for each grain respectively.
I collected 6.5 gallons of wort from the mash tun after final sparge (batch sparged), and gravity at 60F was 1.042. Boiled, and was able to get around 5.25 gallons into fermentor, with SG of 1.049 at 60F.
Calculated either 73.5% or 69% efficiency. Am I correct?
Yep, seems right, but make it easier on yourself. Just use 36 for everything grain when using a calculator. Most programs nowadays will calculate it for each grain.
10.5 x 36 = 378 - it will at worst yield an efficiency slightly less than actual.
42 x 6.5 = 273 so 273 / 378 = 72%
49 x 5.25 = 257.25 so 68%
For more info you can read my blog post on the matter, and also find out why you should be calculating your conversion and lauter efficiencies as well. While mash efficiency is very useful, it’s almost meaningless for figuring out what’s going wrong. http://pricelessbrewing.github.io/methods/Efficiency