Help analyze my results from efficiency calculator

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Apollo

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I used Kaiser's Efficiency Analysis Calculator yesterday and could use some help in improving things. I'll try to be very detailed on the recipe and my process and equipment. I realize this may be long, but I appreciate any help.

First the recipe. I used The Goodness scaled down to 5.5 gallons. Mashed at 156 for 60 min. Crushed at the LHBS at I believe .02 and ran the grains through twice.
9# 2-row
1.25# Caramel 40L
.5# Aromatic Malt
.5# Munich Malt
.5# Flaked Oats
.1# Chocolate Malt

Next my equipment: My mash tun is an old Coleman rectangular cooler which I believe is about 12.8 gallons (I calc'd it from determining how many square inches). I wanted to keep it as a functional cooler as well as a mash tun so when I brew I just stick a hose in the drain stick and put a ss braid on the end of the hose. My kettle is a keggle with a dip tube.

I mashed with 14.8 Qt with a 4 Qt mash out. Batch sparged with 15.4 Qt. Found out I was 4 Qt short of my preboil volume so I heated 10 Qt more and did a second sparge. 4Qt of that sparge went into the kettle and the additional approx 4.5Qt went into a separate pot for a future starter.

First runnings: 10.75Qt @ 1.075 grav
Sparge 1: 11.81Qt @ 1.028
Sparge 2: 8.7Qt @ 1.018
Preboil: 26.6Qt @ 1.042
Postboil: 22Qt @ 1.052

Here's the results from the efficiency calculator:

Conversion efficiency: 96.8%
Efficiency lost in wort not drained into kettle: 5.0%
Efficiency lost in work held back by spent grain: 13.3%
Lauter efficiency: 81.1%

Starches not converted 3.2%
Extract potential lost in wort drained from lauter tun after collecting into the kettle 5.0%
Extract potential held back in the wort held back by the spent grain 13.3%
Extract potential into the boil kettle 65.2%
Extract potential left behind in the kettle -3.0%
Extract potential into the fermenter 68.3
Total. This number should be close to 100% 86.8

I think this about covers it. If I forgot anything let me know. My goal with this is to bump my overall efficiency up to at least 70% (if not 75%). To me it looks like the biggest area that is holding the efficiency low is the extract potential being held back by spent grains. I don't know if there's anything I can do about that. I realize this is a lot of information to analyze but I'm looking to improve my process. Thanks!!
 
since i haven;t read up on what kai has been up to lately he really should be the one to help you..


that being said base grains from different malters will vary on their "ideal" extraction rates. i know that when i switched from dingmans to canadian mallting i lost about 4ppg, ie i went from getting 1.037 from a pound of grain in a gallon of water down to 1.033-34. it is just something to think about and a few maltsters will have a label attached on the sack giving their ideal values.
 
Thanks for posting these results. I'll have to look at them in more detail. So far it has always worked for me but that doesn't mean that it is guaranteed to work for everyone :(

Kai
 
Which of the volume numbers are temperature corrected?

Your numbers track well with what I would expect from batch sparging. Except your pre-boil gravity seems a little low based on the gravity and volumes of the individual run-offs.

I get this:

(10.75 * 75 + 11.81 * 28 + 4 * 18) / 26.6 = 1045

which would be 73%

And if you add the 5% you lost due to having too much water you get 78%

Kai
 
The volume measurements are not corrected for temp. As I drain the mash tun each time, I have a Qt measuring cup I use to get my volumes, so as I get farther along in the drain process, the temp drops some. In the kettle section of the spread sheet, I used 142.8*F for the temp of wort when the volume was measured. I forget exactly when I measured this temp, but suspect it is not accurate for the entire process. The gravity readings are corrected.

Looking back, I'm guessing I didn't stir the first running and the sparges enough to mix them together completely. I thought I had stirred enough, but if the numbers don't add up, then I guess there was an error elsewhere.

So, other than hitting my water volumes, where else do you think I can improve?
Thanks!
 
So, other than hitting my water volumes, where else do you think I can improve?

The grain absorption rate might be something that need to be watched as well. If it's high your lauter efficiency will also suffer.

Kai
 
Apollo,

here is something that might help. I filled you data into my recently completed batch sparge simulation spreadsheet:

http://braukaiser.com/documents/misc_forum/batch_sparge_simulator_for_apollo.xls

The calculated gravities for the individual run-offs match fairly well. Just the total gravity in the kettle is estimated higher than what you measured. That's also why the efficiency calculates higher.

I assumed a grain absorption og 0.12 gal/lb which is lower than what you actually saw since the spreadsheet always calculates that you have more wort available to drain than you actually drained. Larger than expected grain absorption may actually be your main efficiency problem.

If I calculate the apparent grain absorption I see that you used a total of 42.2 q and drained ~31 qt. 11.2 qt or 2.8 gal seem to be stuck in the grain which gives you a grain absorption of 0.24 gal/lb. 0.12-0.14 gal/lb are typical. Are there large dead spaces in your lautertun design?


Kai
 
+1 for checking your MLT deadspace. Double crushing at 0.020 might also explain some of the excessive grain absorbtion. I'm pretty sure I use the same mill as you (at BYOB on Campbell) and do a single crush set at ~0.026. I've been averaging 0.12 gal/lb grain absorbtion and 78% overall efficiency doing it this way.
 
When I was setting up Beer Smith, I measured my dead space to be .13 gallons. I have a feeling that my dead space is somewhat variable. If I leave the tun flat, I'm sure there's more dead space then if I tip it (which I do). I'll measure again this weekend.

Next time I brew, I'll use the .026 setting for my crush.
 
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