How to check efficiency?? - Home Brew Forums

 Home Brew Forums > How to check efficiency??

03-06-2007, 06:32 AM   #1
BG73395
Recipes

Mar 2007
Posts: 16

Hi everyone... I am new to AG and I was wondering how people check the efficiency of the mash...please help a noob out

03-06-2007, 01:13 PM   #2
Lil' Sparky
Cowboys EAC

Recipes

Feb 2006
Honolulu, HI
Posts: 3,959
Liked 73 Times on 46 Posts

Read JP's ch 12-3 through 12-5. http://www.howtobrew.com/section2/chapter12-3.html

Then read the rest of his book!

03-06-2007, 01:22 PM   #3
zoebisch01

Recipes

Nov 2006
Central PA
Posts: 5,182
Liked 10 Times on 10 Posts

Basically you compare your final gravity and the amount of grains in lbs to what the max pppg is for a given grain summed per grain, per amount of your total grain bill. The other thing is that grains aren't always exactly what the numbers are cited at, but for the most part they are fairly consistent from what I understand. This is your extraction efficiency I believe. Oh plus the OG is pre-boil and you need to accurately measure the amount of wort collected.
__________________
Event Horizon ~ A tribute to the miracle of fermentation.

Brew what you like. Do this, and you will find your inner brewer.

03-06-2007, 02:06 PM   #4
grnich
Recipes

Aug 2006
Ottawa, ON
Posts: 162

I use the following calculator:

http://www.tastybrew.com/calculators/gravity.html

I'm not sure, but you might have to sign up to use it.

03-06-2007, 07:11 PM   #5
ESPY
Recipes

Jan 2005
Columbus, OH
Posts: 83

"How to Brew" is a good reference and certainly there's web based calculators and software that'll do it too. But to summarize the manual calculation:

1) Measure the gravity and volume of the wort prior to the boil.

2) Determine the theoretical yield based on your ingredients and wort volume. For this you will need to refer to commonly published yield figures for each type of grain in the recipe (as listed in the "How to Brew" link above). The yield figures are generally reported as points per pound per gallon and represent the maximum possible gravity points from one pound of grain in one gallon of water. Use these figures to calculate the amount of gravity points possible from each grain in your recipe.

3) Calculate efficiency as (Actual gravity points) / (Theoretical gravity points).

Here's a simple example. Suppose you have a basic recipe such as 10 lbs 2-row and 1 lb of crystal-60.

1) You measure your pre-boil as 7 gallons at 1045.

2) Look up the yield values for the grain in your recipe:
2-row: 37 p/p/g
crystal 60: 34 p/p/g

Calculate the theoretical points for 7 gallons of wort:
[(10lbs x 37 p/p/g) + (1lb x 34 p/p/g)] / 7 gal = 57.7 theoretical points

3) Calculate the efficiency: 45 actual points / 57.7 theoretical pts = 78%

It is possible to calculate using your after boil gravity and volume, but not as accurate unless you are able to account for all the losses.

SP