30% efficiency! Help!

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Okay, so I brewed again this weekend and got low (42%) efficiency. What did I do wrong? Here is my process:
--Mash--strike water 5qts at 162*F, 4lbs Marris Otter, 60 min mash, 152 starting temp/ 150 finishing temp.
--1st runnings--3qts @ 1.074 gravity
--Batch Sparge--2 qts @ 162*F
--2nd runnings--2 qts @ 1.060 gravity
--Pre-Boil-- 5qts @ 1.064 gravity
--Boil--60 min.; hop additions--.15oz at 60, .50 at 15, .25 at 10, and .25 at flame out; post boil vol. 4qts
--Into fermentor--3.5(ish) qts, so I added tap water until 1 gallon; S.G. 1.060

I'm tempted to move to BIAB, but I like the easy temp control from mashing in a cooler vs. stove top mashing; I don't have to constantly turn fire on and off to try and maintain temp. Advice anyone?
 
Analysis:

Estimated efficiencies with a 95% conversion (typical value for a good mash):
Mash, 69%
Brewhouse 61% (due to the half quart of loss in the kettle after the boil).

Actual/measured:
Your numbers don't make sense (3*74 + 2* 60)/5 does not equal 64. Likely cause: Inaccurate volumes.

Conversion: 82%. Suggestion, look into grain crush, dough in, and/or mash ph.
Lauter: 56.6% This is pretty low. How did you sparge?
Mash: 53.7% low again. Both conversion and lauter are low, it's too be expected.
Brewhouse 48%, 5% lower than mash due to kettle losses.
 
If you had 100% conversion at the end of your initial mash, your first runnings SG should have been about 1.094 to 1.095, and your second runnings should have been around 1.056. Your pre-boil SG should have been about 1.079 - 1.080.

The fact that your first runnings were only 1.074 indicates that your mash was only about 74 / 94.5 = 78% completed. Your second runnings came out high because the additional time for the sparge allowed some additional conversion to occur, thus raising the SG above what you would have gotten if conversion was complete in the initial mash.

I get your mash efficiency at 49% - 50%.

With a post-boil volume of 1 gal, and pre-boil SG of 1.064 @ 1.25 gal, your post-boil gravity should have been 1 + (0.064 * 1.25 / 1.0) = 1.080. Your OG should have been 1 + (0.080 * 0.875 / 1.0) = 1.070, vs. 1.060, so your measurements are not self consistent. Your OG measurement was probably in error (low) due to insufficient mixing of the dilution water.

Your transfer efficiency was 0.875 gal / 1.0 gal = 87.5%, which makes your brewhouse efficiency 49.5% * 87.5% = ~43%.

If you got your conversion efficiency up to 95%, then your mash efficiency would be about 67%, and your pre-boil SG about 1.076. You should probably be looking into finer crush and verifying your mash pH is in the 5.3 to 5.6 range.

Brew on :mug:
 
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I dont own a mill...I crush 50 + pounds at a time at my LHBS and store it...I dont buy into the whole, have to use the grain up in a few weeks thing if its pre-crushed. Maybe in the humid South but not up here. Try double crushing it if their mill insist getting it fine enough on the first go.

And if you buy a sack of grain at a time..no mail order store should be able to compete with your LHBS. Assuming you have one. I pay 90 cents per pound.
 
You really can't crush it yourself without a mill. You might see some benefit to double milling at the lhbs if possible.
 
Having it milled at my LHBS is not an option; I'm in W.Va., and we have one in the entire state; its about 3 hours away. Everything I get has to be mail ordered. I usually order from Keystone Brewing or Austin Home Brew.
 
Having it milled at my LHBS is not an option; I'm in W.Va., and we have one in the entire state; its about 3 hours away. Everything I get has to be mail ordered. I usually order from Keystone Brewing or Austin Home Brew.

Sounds like you next post then will be to the "What was/is your next major upgrade" thread..:D
 
If you can't mill your own or get your supplier to double crush for you, one thing you can do is mash for a longer time. This allows more time for the larger grits to gelatinize, and gelatinizing the starch is the rate limiting step in the mash. The enzymes act pretty fast once the starch is in solution. Mashing thinner to get a faster conversion rate, and stirring occasionally during the mash may also help (by getting gelatinized surface layers off of the large grits.)

If you want a labor intensive solution to getting a finer crush without a mill, grind about 1 cup of grain at a time in a blender. But, don't over do it and turn it into flour. You want a robust blender for this.

Brew on :mug:
 
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