General Category > All Grain Brewing

Brewing Calculator and Mash Eff

<< < (2/2)

ddcurtis69:
Mash efficiency is calculated from the maximum Ppg of the grain bill you are using, the actual points you get from your pre-boil gravity, and the pre-boil volume. You can research maximum extractable sugar, or Ppg, online for the grains you are using. You then calculate the Maximum Ppg As-Is for each grain on the bill with the following equation:

Max-Ppg As-Is= (Max Ppg*lbs of grain)/pre boil volume

Then you sum up all of the Max-Ppg As-Is for each grain in your grain bill and that is the maximum points you can get from your grain bill and pre-boil volume.

You then measure the pre-boil gravity to calculate your efficiency as below:

If your summed Max-Ppg As-Is = 49 points or a gravity of 1.049 and you measured a pre-boil gravity of 1.040, the mash efficiency is calculated as:

Mash Efficiency= 40/49 = .816 or 81.6%

Beersmith uses brewhouse effiiciency and estimates a mash efficiency. For this to be correct, you must go to your equipment profile and enter your system losses correctly or the estimated mash efficiency will not be right. The brewhouse efficiency is a combination of mash efficiency and system losses to calculate an overall total efficiency. They have some helpful aids on the Beersmith web page to describe this in more detail.

malzig:

--- Quote from: ddcurtis69 on February 11, 2013, 08:42:02 PM ---...You then calculate the Maximum Ppg As-Is for each grain on the bill with the following equation:

Max-Ppg As-Is= (Max Ppg*lbs of grain)/pre boil volume
--- End quote ---
It doesn't have to be pre-boil volume.  Post-boil volume and gravity will give you the same value.

--- Quote ---Beersmith uses brewhouse effiiciency and estimates a mash efficiency. For this to be correct, you must go to your equipment profile and enter your system losses correctly or the estimated mash efficiency will not be right.
--- End quote ---
Beersmith has an implementation of this that continues to confuse people, much like it's bizarre suggestions of multiple small batch sparges.  It may be a lot easier to just do the calculation by hand, using 36 ppg as a decent average potential, if you don't have the actual potential for your lot of grain.

ddcurtis69:

--- Quote from: malzig on February 11, 2013, 11:43:03 PM ---
--- Quote from: ddcurtis69 on February 11, 2013, 08:42:02 PM ---...You then calculate the Maximum Ppg As-Is for each grain on the bill with the following equation:

Max-Ppg As-Is= (Max Ppg*lbs of grain)/pre boil volume
--- End quote ---
It doesn't have to be pre-boil volume.  Post-boil volume and gravity will give you the same value.

--- Quote ---Beersmith uses brewhouse effiiciency and estimates a mash efficiency. For this to be correct, you must go to your equipment profile and enter your system losses correctly or the estimated mash efficiency will not be right.
--- End quote ---
Beersmith has an implementation of this that continues to confuse people, much like it's bizarre suggestions of multiple small batch sparges.  It may be a lot easier to just do the calculation by hand, using 36 ppg as a decent average potential, if you don't have the actual potential for your lot of grain.

--- End quote ---

I totally agree.  I only use pre-boil volume because sometimes I add honey, or other fermentables to the boil that will throw off my mash efficiency if I use post boil gravity.  Yes, I agree the Beersmith implementation is quite confusing and frustrating when you really want mash efficiency to be repeatable.

ukolowiczd:
I use hopville.com. It's free, online, saves recipes and you can set all your own standards like mash efficiency. It's got some bugs but still great.