All Grain OG and Volume a little low...

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Stevorino

Stevorino

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My keggle spigot got clogged by hop leaves at the end (any good suggestions?) and left about a gallon to a gallon and a half of a very hoppy chilled wort in the keggle. I think I ended up getting 4.5 gallons.

I took an OG reading from the remaining hoppy chilled wort I couldn't get into the fermenter and came up short at 1.041 (shooting for 1.049-1.051). What could I have done wrong to come up short (again) on volume and OG?


(11 lbs of grain-- 5 gallons of water in mash, added another 4.5 in second batch sparge-- had 7.5 in boil. Approximately 1 gallon evaporated and 1.5-2 gallons stuck in bottom that I couldn't get from stuck spigot-- total 4.5-5)
 
Wait. 5 gallons in the mash is like 1.8 quarts per pound which is a little high for my tastes. It leaves very little for the sparge. Lean towards 1.25 instead, which would have been more like 3.5 gallons in the mash.

When you say 4.5 in second batch sparge, I think you mean you sparged once with 4.5 gallons. It's on the second batch sparge if you didn't already drain twice.

Just to baseline some terminology....
My first runnings come right from the mash.
Then I infuse a first batch sparge and drain that (second runnings).
Then I infuse a second batch sparge and drain (3rd runnings).

It sounds like you might have added some water to the mash prior to running off anything. This is a "mash out", not technically a sparge yet.

In any case, I recommend 3 discrete runnings.

On the stuck drain in the kettle, you'll either want to install a screen on the drain, something similar to the hop stopper or you'll want to use hop bags. All that wort left in there takes away from your brewhouse efficiency.
 
Bobby_M said:
Wait. 5 gallons in the mash is like 1.8 quarts per pound which is a little high for my tastes. It leaves very little for the sparge. Lean towards 1.25 instead, which would have been more like 3.5 gallons in the mash.

When you say 4.5 in second batch sparge, I think you mean you sparged once with 4.5 gallons. It's on the second batch sparge if you didn't already drain twice.

Just to baseline some terminology....
My first runnings come right from the mash.
Then I infuse a first batch sparge and drain that (second runnings).
Then I infuse a second batch sparge and drain (3rd runnings).

It sounds like you might have added some water to the mash prior to running off anything. This is a "mash out", not technically a sparge yet.

In any case, I recommend 3 discrete runnings.

On the stuck drain in the kettle, you'll either want to install a screen on the drain, something similar to the hop stopper or you'll want to use hop bags. All that wort left in there takes away from your brewhouse efficiency.
Click to expand...

Bobby, you're my hero.

To clarify, I had 5 gallons worth of first runnings, then I added 4.5 gallons at 150 degrees for second runnings. Never did a third. Will do next time.

Yeah, I need to get some kind of screen-- that sounds fairly necessary.

Any ideas on the OG being so low?
 
Yeah, the low OG was just having really low efficiency. I think it's because of your really high volume of mash water. In order to get 5 gallons of first runnings, you must have infused a total of about 7 gallons prior to first runnings. That's a lot.

Let's suppose you doughed in your 11 pounds of grain with only 3.5 gallons.
At the end of the 60minute mash, vorlauf and drain. Given that grain usually absorbs about .1 gallons per pound, I'd expect you to get out only 2.4 gallons on first runnings.

If you want 7.5 gallons in the kettle, that means you need to sparge about 5 gallons (7.5 - 2.4 = 5.1 gallons).

In order to maximize efficiency (in my experience), break that 5.1 gallons into two 2.5 gallon batches at about 180F.

You'll easily meet your OGs next time, if not overshoot them. In order to troubleshoot the process, I recommend taking gravity readings of each running. The last running should be 1.020 or lower. If it's higher, the process can use tweaking.
 
That sounds good-- Is there anything I can/should do to this brew or do you think it'll turn out okay w/ the low OG?
 
Stevorino said:
Bobby, you're my hero.

To clarify, I had 5 gallons worth of first runnings, then I added 4.5 gallons at 150 degrees for second runnings. Never did a third. Will do next time.

Yeah, I need to get some kind of screen-- that sounds fairly necessary.

Any ideas on the OG being so low?
Click to expand...

For the second runnings, you need to heat the sparge water to at least 170. (After mixing with the grain, you want the water to stabilize at about 165 - 170.) Low temps will contribute to low OG.

-a.
 
ajf said:
For the second runnings, you need to heat the sparge water to at least 170. (After mixing with the grain, you want the water to stabilize at about 165 - 170.) Low temps will contribute to low OG.

-a.
Click to expand...

That's what I remember being told and reading-- why does Clonebrews suggest you sparge at 150?
 
For an extact with steeping grains, where you are only trying to extract the flavor from the speciality grains, 150 wouldn't be out of line, but that's not sparging where the objective is to extract the sugars.

-a.
 
ajf said:
For an extact with steeping grains, where you are only trying to extract the flavor from the speciality grains, 150 wouldn't be out of line, but that's not sparging where the objective is to extract the sugars.

-a.
Click to expand...


Makes sense-- I wonder how much of my OG discrepancy is due to the temperature error...
 

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