I think I still have efficiency issues....

[Hwk-I-St8]

Tell me if I'm doing this right:

Theoretical ppg is 528.6 (sum of ppg for each grain * # lbs)
Volume first runnings: 3.3 gals @ 1.071
Volume second runnings 3.6 gals @ ? (forgot to check)
Pre-boil volume 6.9 gals at 1.050

Actual points extracted: 50 * 6.9 = 345
Lauter efficiency: 345/528 = .65 = 65% (seems really low)

I had 5.2 gals into ferm at 1.064 = 332 points.
Brewhouse efficiency = 332/528 = .629 = 62.9% (amazingly close to lauter efficiency)

This is typical of my results. I usually figure 61-62% and come in very close on my gravities.

Looking at this, it looks like my lauter efficiency sucks. I'm not sure if it's the ubiquitous crush and conversion efficiency or if my batch sparge process is the problem. I always set up my numbers so that first and second runnings are close to the same. In this case, mash thickness was 1.5 G/lb.

Thoughts?

 

[beermanpete]

Your calculations look right. You have what appears to be a typo (332/345 that should be 332/528).
The brewhouse efficiency includes losses in the boil kettle and hoses. The small drop from lauter efficiency indicates you are not losing much wort after the boil.

Improving mash/lauter efficiency will be a trial and error process. As a place to start, your data suggests you used about 14 lbs of malt. If this is correct your mash is 0.9 qts of water per pound of malt which too dry. Try using about 1.25 to 1.5 qts/lb for the mash which is 4.4 gals to 5.25 gals of water. Depending on your boil kettle volume you may have to reduce the sparge volume a bit so it all fits.

 

[doug293cz]

65% is your mash efficiency. Mash efficiency equals conversion efficiency times lauter efficiency. Conversion efficiency is sugar created in mash divided by potential sugar. Lauter efficiency is sugar into BK divided by sugar created in mash. Lauter efficiency is determined by grain absorption and the concentration of sugar in wort left in the grain bed. If you have your strike volume recorded you can determine your conversion efficiency from your grain bill weight and first runnings SG using the method here. Once you know your conversion and mash efficiencies you can calculate your lauter efficiency. Then you can compare your efficiencies against what constitutes "good" conversion (95%+) and good lauter (70 - 88%) depending on size of grain bill) efficiencies. Then you know what you need to work on. My guess is that it will be conversion efficiency, and be a result of poor crush.

So, what was your strike volume and grain bill weight?

Brew on

 

[doug293cz]

...

Improving mash/lauter efficiency will be a trial and error process. As a place to start, your data suggests you used about 14 lbs of malt. If this is correct your mash is 0.9 qts of water per pound of malt which too dry. Try using about 1.25 to 1.5 qts/lb for the mash which is 4.4 gals to 5.25 gals of water. Depending on your boil kettle volume you may have to reduce the sparge volume a bit so it all fits.

You forgot to allow for grain absorption (about 0.12 gal/lb) when figuring OP's strike volume.

I estimate OP's grain bill at 14.3 lb, so grain absorption would be 14,3 * 0.12 = 1.71 gal, and strike volume would be about 3.3 + 1.7 = 5 gal. That would put OP's mash thickness at 5 * 4 / 14.3 = 1.4 qt/lb. Much more reasonable than 0.9 qt/lb.

Assuming these guesstimates are anywhere close to reality, OP's conversion efficiency is about 80%, and lauter efficiency at about 83%. This would make OP's' efficiency issues due to conversion efficiency.

Brew on

 

[Hwk-I-St8]

Your calculations look right. You have what appears to be a typo (332/345 that should be 332/528).
The brewhouse efficiency includes losses in the boil kettle and hoses. The small drop from lauter efficiency indicates you are not losing much wort after the boil.

Improving mash/lauter efficiency will be a trial and error process. As a place to start, your data suggests you used about 14 lbs of malt. If this is correct your mash is 0.9 qts of water per pound of malt which too dry. Try using about 1.25 to 1.5 qts/lb for the mash which is 4.4 gals to 5.25 gals of water. Depending on your boil kettle volume you may have to reduce the sparge volume a bit so it all fits.

I have 5.4 gallons going into the mash, 3.3 coming out with a grain bill of 14.5 lbs.

5.4*4 = 21.6 qt / 14.5 lbs = 1.49 qts/lb

 

[Hwk-I-St8]

65% is your mash efficiency. Mash efficiency equals conversion efficiency times lauter efficiency. Conversion efficiency is sugar created in mash divided by potential sugar. Lauter efficiency is sugar into BK divided by sugar created in mash. Lauter efficiency is determined by grain absorption and the concentration of sugar in wort left in the grain bed. If you have your strike volume recorded you can determine your conversion efficiency from your grain bill weight and first runnings SG using the method here. Once you know your conversion and mash efficiencies you can calculate your lauter efficiency. Then you can compare your efficiencies against what constitutes "good" conversion (95%+) and good lauter (70 - 88%) depending on size of grain bill) efficiencies. Then you know what you need to work on. My guess is that it will be conversion efficiency, and be a result of poor crush.

So, what was your strike volume and grain bill weight?

Brew on

strike volume was 5.4 gallons.
grain bill 14.5 lbs
first runnings 3.3 gallons at 1.071

 

[beermanpete]

You forgot to allow for grain absorption (about 0.12 gal/lb) when figuring OP's strike volume.

Yes, I did. Thank you for the correction.

I have 5.4 gallons going into the mash, 3.3 coming out with a grain bill of 14.5 lbs.

5.4*4 = 21.6 qt / 14.5 lbs = 1.49 qts/lb

strike volume was 5.4 gallons.
grain bill 14.5 lbs
first runnings 3.3 gallons at 1.071

Ok, one item off the list. What size is your boil kettle? If you have the volume for it add some more sparge water to the second batch or do a thirf batch.

Grain milling is important. How is your malt being milled? Do you have any control over the process?

 

[doug293cz]

strike volume was 5.4 gallons.
grain bill 14.5 lbs
first runnings 3.3 gallons at 1.071

Ok, using those numbers I get:

Conversion Efficiency: 85.3%
Lauter Efficiency: 79.3%
Mash Efficiency: 67.7%
First Runnings SG: 1.071
Sparge Runnings SG: 1.032
Pre-Boil SG: 1.0505
Apparent Grain Absoprtion Rate: 0.145 gal/lb​

The fact the the simulated pre-boil SG is close to the measured pre-boil SG gives me confidence in the validity of the simulation, and means your volume and SG measurements don't appear to contain any significant errors.

Your conversion efficiency is less than desirable, so improvement efforts should be focused there. Finer crush and/or longer mash times can improve the conversion percentage. Also, are you doing anything to control mash pH? pH out of the range of about 5.3 to 5.6 can slow the conversion process, which can result in incomplete conversion.

Your grain absorption rate is high (0.145 gal/lb vs. typical of 0.12), which lowers your lauter efficiency somewhat. This calculated absorption rate assumes you have no undrainable volume in your MLT. If you do have undrainable volume, then your grain absorption rate is actually lower. If we assume an absorption rate of 0.12, then that would require an MLT undrainable volume of 0.36 gal, which is pretty high compared to a good MLT design. Undrainable volume reduces lauter efficiency in a similar fashion as grain absorption, except the effect is not variable with grain bill size. If you do have undrainable volume, you can increase your lauter efficiency by reducing or eliminating it.

Brew on

 

[Hwk-I-St8]

Yes, I did. Thank you for the correction.





Ok, one item off the list. What size is your boil kettle? If you have the volume for it add some more sparge water to the second batch or do a thirf batch.

Grain milling is important. How is your malt being milled? Do you have any control over the process?

10 gallon boil kettle. Malt is milled at the LHBS. Getting my own mill is high on the priority list.

 

[Hwk-I-St8]

Ok, using those numbers I get:

Conversion Efficiency: 85.3%
Lauter Efficiency: 79.3%
Mash Efficiency: 67.7%
First Runnings SG: 1.071
Sparge Runnings SG: 1.032
Pre-Boil SG: 1.0505
Apparent Grain Absoprtion Rate: 0.145 gal/lb​

The fact the the simulated pre-boil SG is close to the measured pre-boil SG gives me confidence in the validity of the simulation, and means your volume and SG measurements don't appear to contain any significant errors.

Your conversion efficiency is less than desirable, so improvement efforts should be focused there. Finer crush and/or longer mash times can improve the conversion percentage. Also, are you doing anything to control mash pH? pH out of the range of about 5.3 to 5.6 can slow the conversion process, which can result in incomplete conversion.

Your grain absorption rate is high (0.145 gal/lb vs. typical of 0.12), which lowers your lauter efficiency somewhat. This calculated absorption rate assumes you have no undrainable volume in your MLT. If you do have undrainable volume, then your grain absorption rate is actually lower. If we assume an absorption rate of 0.12, then that would require an MLT undrainable volume of 0.36 gal, which is pretty high compared to a good MLT design. Undrainable volume reduces lauter efficiency in a similar fashion as grain absorption, except the effect is not variable with grain bill size. If you do have undrainable volume, you can increase your lauter efficiency by reducing or eliminating it.

Brew on

Great info here. I appreciate you guys taking the time to help analyze this.

For pH, I use Bru'n Water. I started out borrowing a meter and checking, but the calculated pH was always pretty close. Since all my beers to date have been a very similar grain bill in size and makeup, I pretty much just trust the calcs. In this recipe, I added 2 oz of acidulated malt. I start with RO water and build up a water profile appropriate for a NEIPA. pH should be around 5.3.

I use a rectangle cooler with a bazooka tube and I've estimated about a quart of undrainable volume. I don't really know how to correct that with this MLT. I'm open to ideas however.

 

[doug293cz]

Great info here. I appreciate you guys taking the time to help analyze this.

For pH, I use Bru'n Water. I started out borrowing a meter and checking, but the calculated pH was always pretty close. Since all my beers to date have been a very similar grain bill in size and makeup, I pretty much just trust the calcs. In this recipe, I added 2 oz of acidulated malt. I start with RO water and build up a water profile appropriate for a NEIPA. pH should be around 5.3.

I use a rectangle cooler with a bazooka tube and I've estimated about a quart of undrainable volume. I don't really know how to correct that with this MLT. I'm open to ideas however.

Looks like pH is not an issue.

Eliminating your MLT undrainable volume could give you about a 3 percentage point improvement in your lauter efficiency. On the other hand, getting better conversion could get you 9 to 14 points improved conversion efficiency. A grain mill looks like your biggest bang for the buck.

Brew on

 

[beermanpete]

Talk with the LHBS about this. They are likely brewers and hopefully know the efficiency of their system and presumable they use the same malt mill. If there is a homebrewers club club associated wit the store you could ask some of the club members about this. Some of them are likely to use the same mill.

 

[Hwk-I-St8]

Thanks everyone. I've been on the verge of picking up a mill for multiple reasons (resolving efficiency is just one of them). I think I'll just bite the bullet and snag one.