Efficiency And Gravity Help Please

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symphony1975

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hi
i have done 4 batches of all grain brewing now (urn for HLT, esky mashtun and kettle) and am trying to iron out a few numbers in beersmith. i have been hitting my volumes:

32L pre boil
4.5L boil-off (14% per hr)
1.0L cooling loss
5.5L trub loss
21L into fermenter

i am also hitting my strike water temp, mash temp, P/H (batch sparge, 1 sparge)

currently 66% efficiency.

for the last 2 batches i have been 7 points under target pre boil gravity and 11 points under target OG.

i was expecting that if you have your volumes correct for the boil process that your gravity would be out by the same amount for pre boil and OG. i.e if preboil is 7 points under, OG will also be 7 points under. Therefore the above gravity readings would indicate not enough boiling of the wort.

am i way off the mark?

how would you interpret these numbers?

thanks for your help....
 
Is the boil off volume correct between actual and estimate? If you boil off more/less than expected, that will also effect your gravity readings.
 
Is the boil off volume correct between actual and estimate? If you boil off more/less than expected, that will also effect your gravity readings.
yes these are the estimate volumes which i have accurately been hitting. i have been measuring all the volumes and have been stoked to see i have been hitting them

Are you measuring samples at the same temp ?

yes samples are all measured at 20 degrees which my thermometer and hydrometer and refractometer are calibrated at.
 
whilst I'm still new to the game... if your volumes are right, and your readings are right - it seems your efficiency is out, right?

I've found when measuring my strike temp that my thermometer takes some time to finalise its reading, in fact both my thermometers do - subsequently before discovering this, I was getting substandard efficiency as I was mashing too high. Is there a possibility you may be experiencing this?
 
what are the actual gravity readings you got?
 
whilst I'm still new to the game... if your volumes are right, and your readings are right - it seems your efficiency is out, right?

I've found when measuring my strike temp that my thermometer takes some time to finalise its reading, in fact both my thermometers do - subsequently before discovering this, I was getting substandard efficiency as I was mashing too high. Is there a possibility you may be experiencing this?
yes i am sure my efficiency is out but i am trying to make sense of the gravity readings before adjusting my efficiency.

my thermometer stays in the HLT so there isnt an issue with giving the thermometer time.

what are the actual gravity readings you got?

so the estimated gravity was:
pre boil - 1056
OG - 1068

actual readings:
pre boil - 1049
OG - 1057

so pre boil 7 points under
and OG 11 points under
 
Id guess that your boil rate is incorrect and should be lower and that your volume measurements are wrong for the five point difference in gravity targets. Plug in 12% next brew and see how that fares.

5.5 l trub seems high to me but i have a one vessel system, however even when i did biab and squeezed it wasnt that high. Some 3V brewers might give some advice on this?

When i did biab i filtered the trub through some voile/ cheesecloth to improve wort recovery, you might want to try this to gain some effeciency until you can reduce trub content to be more inline with other 3 V brewers.
cheers
sean
 
re the 5.5L trub.....the tap on my kettle is at a height that requires 5.5L trub otherwise i have to tip it and trying to hold hose to fermenter, balance kettle (with immersion chiller) and gently tip so as to not tip break material and hops etc into fermenter is a tad tricky for my little arms! so i wound up the loss to trub amount so i just turn kettle tap and 21L pours into fermenter while a grab a beer.....

thanks for the tip on evaporation rate. i will plug in 12% and see how that goes
 
The tap on my urn left a fair bit too,if your valve is attached to pot with a threaded nipple then you can screw on a ss angle and hose barb. Have done this on my rig and bugger all waste now.
 
Also there is no reason to have your immersion chiller
in the kettle when you are syphoning to the fermentor.

Regards

Graeme
 
I usually get around 4-5L of trub left in the bottom of my pot after filling my cube. I then tip the pot up and pour all of the trub into a 5L jug, then cover it with gladwrap and leave it in the fridge overnight. In the morning I usually have around 2L of clear wort that I can pour off and use in a mini boil for my late hop additions (I no-chill and use Argon's method for late hop additions). That will help your efficiency and give you another 2+ longnecks of finished product for your troubles.
 
so the estimated gravity was:
pre boil - 1056
OG - 1068

actual readings:
pre boil - 1049
OG - 1057

Something looks wrong in the estimated values.

49 (pre boil gravity) * 32 (pre boil volume) / 27.5 (post boil volume) = 57 (post boil gravity) So your actual readings are correct

56 * 32 / 27.5 = 65 not the 68 from the software. Which makes your actual 8 below expected (not 7, but there is probably rounding off somewhere to account for that)
 
actual readings:
pre boil - 1049
OG - 1057


32L starting volume @ 1.049, 1L cooling loss, 14% boiloff, 60 min boil time should result in around 1.059 in theory. You were close, no problem other than low mash efficiency as far as I see.

Screwy
 
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