VoceWeiser said:
I am only about a month into this, so be nice. How can you measure your efficiency? How can you tell if you are at 60, 70 or 80 percent?
Within brewing there are two types of efficiency. Both are related to sugar yield (extract) from grain. Various grains have varying yields, but BeerSmith calculates them individually and totals them to get an accurate efficiency number.
Mash Efficiency: This is the percentage of sugar pulled from grain, based on its total potential yield. It means the yield of one lb of grain mashed to make one gallon of wort. The measurements become "Points per Gallon" or ppg (sometimes pppg). To get that number, multiply the preboil starting gravity by the volume, then divide that by the grain weight in pounds.
The total potential is based on a lab procedure called "Congress Mash" which pulls everything solubol out of the grain. This is not a procedure a homebrewer needs to do. BeerSmith has the typical potential in each grain. It's just a reference point for comparing recipes and malts.
You don't actually want everything that's soluble from the grain. Tannins and gums, for instance, are best left behind. So, the brewer's mash efficiency will always be less than 100%. Homebrewers tend to get 70 to 80% of what's available. Pro brewers tend to get 90+%.
Brewhouse Efficiency: This is the number that BeerSmith uses. It takes the mash efficiency a few steps further by being an expression of how much sugar actually makes it into the fermenter. Within BeerSmith it's strongly effected by the "Loss to Trub and Chiller" number in the equipment profile. BE tallies up the mash efficiency PLUS all of your losses, post boil, so it's always lower than your mash efficiency number.
Unless you're pouring 100% of your kettle into the fermenter, there will always be some spent hops and protein break in the bottom of your kettle. Brewhouse Efficiency will figure that as a percentage of the total wort produced and a loss of sugar to the fermenter.
A half gallon of trub loss to a fermenter yield is 8.3% of the total. So, BE can't be any better than 91.6%. However, you then multiply that by your expected mash efficiency to get your actual BE. So, with an expected mash efficiency of 75%, you get: 0.916 x 0.75 = 0.687 or 68.7% Brewhouse Efficiency.
If you accurately measure volumes, losses and gravity, BeerSmith will calculate your BE. It'll be on the Fermentation page as "Measured Efficiency." You can just use that number in your equipment profile for better accuracy.