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Old 05-26-2012, 07:57 PM   #1
Moonraker
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Jun 2011
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Mash today gave me 6.25 gallons at 1.058 (1.041 @ 145F). Before pitching I had 5.0 gallons at 1.064 (1.062 @ 80F). I would have expected to get 1.072 (i.e. 58 x 6.25 / 5).

Is there a rational explanation for where the sugar is going? I'm as careful with the hydrometer as I can be, and getting the wort mixed well before sampling.



 
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Old 05-26-2012, 08:04 PM   #2
neosapien
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my bet is that the sugar never went anywhere. it was never there to begin with. from 1.058 -> 1.064 was just a matter of your boil-off. the fact that you expected to hit 1.072 means your efficiency was just not as high as expected. look to things like mash time/temp, grain mill size, etc. to improve that number. Also, as much as you mix the wort after you top off, it's still possible to find a non-homogenous region in it, so that may account for it as well.



 
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Old 05-26-2012, 08:12 PM   #3
Moonraker
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Jun 2011
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The 1.058 is after the mash, so mash time, grain mill size etc not a factor after that point. I had 77% mash efficiency , which I'm happy enough with.

I did forget to factor in loss to hop sludge, which I measured at a little over half a quart. Even calling that a whole quart would mean I should have gotten 1.069 (54 * 6.25 / 5.25). I leave nothing in the kettle...

 
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Old 05-26-2012, 08:26 PM   #4
Moonraker
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Jun 2011
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Quote:
Originally Posted by neosapien
my bet is that the sugar never went anywhere. it was never there to begin with. from 1.058 -> 1.064 was just a matter of your boil-off. the fact that you expected to hit 1.072 means your efficiency was just not as high as expected. look to things like mash time/temp, grain mill size, etc. to improve that number. Also, as much as you mix the wort after you top off, it's still possible to find a non-homogenous region in it, so that may account for it as well.
Sorry, I should have at least said thankyou for the response - was in a hurry to get out the door and to the pub.

 
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Old 05-26-2012, 08:29 PM   #5
ShinyBuddha
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Dec 2011
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So you dump the cold break and the vegetative material from the hops into the fermenter? Why don't you use hop bags? Just curious. I make 6.5 gallon batches to end up with 5 gallon batches in the keg/bottles. I plan on loosing 1 gallon to the brew kettle (trub & cold break) and another .5 gallons to the fermenter (yeast & whatever else settles out).

 
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Old 05-26-2012, 08:42 PM   #6
Moonraker
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Jun 2011
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Quote:
Originally Posted by ShinyBuddha
So you dump the cold break and the vegetative material from the hops into the fermenter? Why don't you use hop bags? Just curious. I make 6.5 gallon batches to end up with 5 gallon batches in the keg/bottles. I plan on loosing 1 gallon to the brew kettle (trub & cold break) and another .5 gallons to the fermenter (yeast & whatever else settles out).
I read somewhere here that you get more flavour out of the hops if you let them roam free. I used to use hop bags and still got a fair amount of sludge. Now I just pour everything through muslin into a bottling bucket before racking to a carboy. I figure anything the muslin doesn't catch will end up in the trub at the bottom of the carboy after three weeks and be left behind before bottling.

 
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Old 05-26-2012, 08:43 PM   #7
neosapien
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Quote:
Originally Posted by Moonraker View Post
Sorry, I should have at least said thankyou for the response - was in a hurry to get out the door and to the pub.
THAT is a worthy cause

 
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Old 05-26-2012, 09:24 PM   #8
Yooper
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Remember that any reading with wort above about 90 degrees is worthless- even with conversion tables/correction software it is notoriously accurate. So I would say the sample at 145 degrees is simply wrong.

Next time, cool the sample in a water/ice bath in a pitcher to under 90 degrees and then take the reading. At that point, it can be temperature corrected to an accurate reading.
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Old 05-26-2012, 09:58 PM   #9
Moonraker
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Jun 2011
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Quote:
Originally Posted by Yooper View Post
Remember that any reading with wort above about 90 degrees is worthless- even with conversion tables/correction software it is notoriously accurate. So I would say the sample at 145 degrees is simply wrong.

Next time, cool the sample in a water/ice bath in a pitcher to under 90 degrees and then take the reading. At that point, it can be temperature corrected to an accurate reading.
Ah, this I was not aware of. Excellent, thanks. My faith in physics may be restored.

 
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Old 05-26-2012, 10:12 PM   #10
neosapien
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Quote:
Originally Posted by Yooper View Post
Remember that any reading with wort above about 90 degrees is worthless- even with conversion tables/correction software it is notoriously accurate. So I would say the sample at 145 degrees is simply wrong.
Whoops! Totally missed that part of the OP. That'll teach me to talk without reading all the words!



 
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