Grain absorption question

Looking for reasons why my grain absorption is so high, at least high in my mind. I made a recipe with a grain bill of 12lbs. I initially started with 3.25 gallons water. I didn’t quite hit mash temp so I quickly added about another gallon, giving me about 4 gallons or maybe a little more in the mash. One hour later I drain and get exactly two gallons out. How is this possible? It seems to happen on all my mashes. They all seem to absorb a lot more than the norm. I try to stick with the usual 1.25 galls per lb of grain but this is obviously not enough. Tried 1.5, not enough. Anyone else experiencing this or is it something I am doing wrong? Or is this just the way it is for me?

Grain typically absorbs 1/2 qt water per a lb. SO on a 12lb grain bill, you could expect to lose 1.5 gallons to grain absorbtion.

As for the other 1/2 gallon you are losing I would attribute that to the dead space in your mash tun.

What type of mash tun do you have? False bottom, SS braid, manifold? Batch or fly sparge?

I believe it is a 48 quart cooler with a SS braid. I can also promise you there is not that much dead space going on. I am tilting this thing to grab every single drop I can. I am very patient with that. I may leave some behind but I can promise you after clean up there is no wheres near even a quart left. We are talking MAYBE a cup, maybe two left behind.

If it’s not dead space, then it might be your volume measurements.

Can’t be. I use a plastic measuring container that holds up to one gallon that has all the measurements on the side. I know EXACTLY how much I put in and take out. Not trying to be a smartass, just letting you know what I use

Maybe the extra half gallon is being absorbed by the grain. It could be that with such a large cooler and small grain bill, the grain depth is only 10 inches or so. This low grain depth would reduce the pressure being placed on the grain, reducing the amount of wort that is squeezed out by the wieght of the grain.

I know that the absorbtion in my round cooler mash tun is 1/2qt per lb, and that is with a grain depth near 24 inches, theoretically twice the pressure compressing the wort out of the grain.

Just a thought.

You’re not being a smartass. :wink:

So if it’s not your measurements and not deadspace, then as gregscu mentioned above, it might be that the grain isn’t draining completely - next time you brew, keep the hose attached to the valve and put a bucket on the ground, let the siphon work on it for 30 minutes, see what you get. Yesterday I pulled an extra gallon of wort out of a 36# mash letting it slowly siphon overnight (I mashed and brought the wort to a boil then shut it off and went to bed, finished in the AM).

How long are you allowing to drain the first runnings? It sometimes takes me 20 minutes or longer to get close to my first runnings volume.

I’d get as much as I can from the first runnings in a reasonable amount of time then begin the sparge. When I’m close to my boil volume I start the boil and collect the rest in another pot and add it prior to the boil commencing.

That brings up another question. Is it possible to do the mash say at night and drain it and then boil the next day? Just a thought.

I would say 10-20 minutes. I get very very little to no grains at all in my drains so I tend to let it fly so to speak but then it will slow down and that is when I begin tipping back and forth to get every single drop I can.

Do you mean “gallons” or a different unit of measurement? I believe you meant “quarts” and that is the ROT I use as well. Are you using alot of wheat malt in your grain bill? I will got with a little extra water if doing a hefe.