Someone Splain Water Usage To Me.

[PanzerOfDoom]

Let's say a recepie calls for 4 gallons in the mash and 5 gallons of sparge to = 9 gallons, will you end up with 6 for the boil due to loss from absorbtion from the grain bed?

I am building a mashtun and anticipate doing my first all grain within the month, any and all advice welcome.

 

[RichBrewer]

It all depends on how much grain you use. Figure approximately .1 gallons per pound will be absorbed by the grain.
Also, figure 1 quart of water per pound for the mash and 1/2 gallon per pound for sparging.

12 pounds of grain would look something like this:

3 Gallons water for mash.
6 Gallons of sparge water
water absorbed by grain approx 1.2 gallons
Wort in brew kettle 7.8 or about 7 3/4 gallons.

Now you will also have to figure out how much wort you will lose during the process. If there is any dead space in the mash/Lauter tun you will lose some there and you will loose some in the brew pot due to trub and gunk in the bottom of the pot.

 

[Lost]

The normal mash thickness is about 1.2-1.4 quarts per lb. Thicker mashes will tend to convert faster (enzymes are not as diluted in the water) and will be less fermentable. For 11lbs of grain you'd need around 3.5 gallons in the mash. A general rule of thumb is that you should no more than double the mash volume for your sparge.. that means you'd need 5.5 to 7 gallons or so for the sparge in this hypothetical batch. Obviously, your kettle may put a restriction on how much wort you can get out of the grains.. so you could thicken the mash a bit in hopes of leaving more space for the sparge runnings. For this batch you'd end up with around 8 gal in the kettle and you could boil this down to whatever batch size you need or whatever gravity you're aiming for.

You should stop sparging if the ph of the runnings hits 6 or above. While somewhat debatable, you can also lower the ph of the sparge water before it hits the mash by using some lactic acid. This is almost certainly unnecessary with darker, more acidic grains (i.e. porter or stout) but is worth considering if you're brewing a lighter colored beer. Of course, if your water is not extremely hard or soft then you can probably brew great beer without even getting into water chemistry.. just something to think about. Another good failsafe is to stop sparging when the runnings drop below 1.008.

 

[Lounge Lizard]

I'm wondering how many guys (and gals) actually measure how much strike water they use? After a little experience, couldn't you just keep adding water until the mash looks like the right consistency? Maybe just make sure the grain bed is totally soaked, and then add a couple of inches of water on top?


Thanks...

 

[RichBrewer]

I'm wondering how many guys (and gals) actually measure how much strike water they use? After a little experience, couldn't you just keep adding water until the mash looks like the right consistency? Maybe just make sure the grain bed is totally soaked, and then add a couple of inches of water on top?


Thanks...

I've always used 1 quart per pound of grain and I've had good results. I bet you could just guess at it and get it pretty close but I like to keep it consistent.