Originally Posted by dest149
I have been looking into sparging, but it still kind of confuses me. I looked at John Palmer's site, but it just does't add up for me. I get that you are rinsing water over the grains you take out, but the amoount and how you do it doesn't add up. For example
"Sparging is the rinsing of the grain bed to extract as much of the sugars from the grain as possible without extracting mouth-puckering tannins from the grain husks. Typically, 1.5 times as much water is used for sparging as for mashing (e.g., 8 lbs. malt at 2 qt./lb. = 4 gallon mash, so 6 gallons of sparge water). " - From howtobrew.com
It says 4 gallons of mash and 6 gallons of sparge. Thats 10 gallons. How does that work out for a 5 gallon brew?
Well, he does say "typically", not must be. And usually, you don't want more than about 3 quarts/pound of water going through your grain. Most brewers don't do such a thin mash as 2 quarts/pound.
Here's what I do. I will use an example of a 10 pound grainbill (5 gallon batch) for the ease of doing the math!
10 pounds grain @ 1.5 quarts/pound (but 1.25-2 is acceptable)- 15 quarts (3.75 gallons).
The grain will usually absorb .125 gallons per pound, so figure I'll "lose" 1.25 gallons to absorption.
That means I'll get out 2.5 gallons of first runnings.
For a 5 gallon batch, I want to start with 6.5 gallons in the kettle. That means I want 4 gallons of sparge water.
You CAN use more sparge water. That will increase the amount of sugars extracted, however will require more boiling time. Most brewers I know stop when they reach their boil volume and don't extract as much sugar as they potentially could because they don't want to boil down for 3 hours.