# Homebrewers Association | AHA Forum

## General Category => All Grain Brewing => Topic started by: micsager on October 14, 2010, 03:50:27 PM

Title: Mash efficiency
Post by: micsager on October 14, 2010, 03:50:27 PM
Well guys, I finally ordered a sight guage for my HLT, so I can know for certain how much water I was added to the mash.  (I had been just eyeballing to what I perceived as a good water/grain ratio.  It seemed the next step for my brewing system.

And I will be able to calculate my mash efficiency since I will know with great accuracy how much water I'm using.  Can someone explain how to do such?  I've read Palmer's book on it, and read some other forums, but it's still a bit confusing to me........
Title: Re: Mash efficiency
Post by: hopfenundmalz on October 14, 2010, 03:58:41 PM
Kai has a better write up than I could do.
http://braukaiser.com/wiki/index.php/Understanding_Efficiency

He also gave this talk at the NHC, which I have heard was excellent.
http://www.homebrewersassociation.org/attachments/0000/4797/A_Closer_Look_at_Efficiency-Kai_Troester.pdf

Hope that helps.

Edit: link fixed - thanks for the catch Sean.
Title: Re: Mash efficiency
Post by: a10t2 on October 14, 2010, 04:04:02 PM
Pretty simple calculation. Essentially you just need to divide your actual sugar extracted by the total amount of sugar (potential extract) in the grains. The total amount of sugar is just the gravity of the wort multiplied by the volume (so "point-gal" typically for a unit). The potential extract is the sum of the extracts for each type of grain in the grist, weighted proportionally.

For a really simple example, say you're brewing a pale ale with 9 lb of 2-row and 1 lb C60, and you collected 6.5 gal of 1.040 wort. Looking up the extract of the grains (this chart is handy (http://www.homebrewtalk.com/wiki/index.php/Malts_Chart)) you find they're about 37 and 34 point-gal/lb, respectively. The potential extract is:

9*37 + 1*34 = 367 point-gal

You collected 6.5*40 = 260 point-gal, so the efficiency is 260/367 = 0.708, about 71%.

edit: I think the link to Kai's writeup was supposed to be: http://braukaiser.com/wiki/index.php/Understanding_Efficiency
Title: Re: Mash efficiency
Post by: micsager on October 14, 2010, 04:47:25 PM
Pretty simple calculation. Essentially you just need to divide your actual sugar extracted by the total amount of sugar (potential extract) in the grains. The total amount of sugar is just the gravity of the wort multiplied by the volume (so "point-gal" typically for a unit). The potential extract is the sum of the extracts for each type of grain in the grist, weighted proportionally.

For a really simple example, say you're brewing a pale ale with 9 lb of 2-row and 1 lb C60, and you collected 6.5 gal of 1.040 wort. Looking up the extract of the grains (this chart is handy (http://www.homebrewtalk.com/wiki/index.php/Malts_Chart)) you find they're about 37 and 34 point-gal/lb, respectively. The potential extract is:

9*37 + 1*34 = 367 point-gal

You collected 6.5*40 = 260 point-gal, so the efficiency is 260/367 = 0.708, about 71%.

edit: I think the link to Kai's writeup was supposed to be: http://braukaiser.com/wiki/index.php/Understanding_Efficiency

So I need to install the sight gauage on my boil pot?  I thought it would go on the HLT?????
Title: Re: Mash efficiency
Post by: euge on October 14, 2010, 05:03:10 PM
In an ideal setup (in my brewery) I'd have a sight glass on both. You'll still have to account for expansion. That's what throws most people off IMO. They may think they're using a certain volume but it turns out to be much less when all is said and done and the wort cools.
Title: Re: Mash efficiency
Post by: a10t2 on October 14, 2010, 05:18:14 PM
So I need to install the sight gauage on my boil pot?  I thought it would go on the HLT?????

You don't need a sight gauge, just a way to measure volume. Markings on a stick or spoon work fine.
Title: Re: Mash efficiency
Post by: jaybeerman on October 14, 2010, 05:27:55 PM
Just a thought - put the sight glass on the hlt.  Find a stainless section of pipe or even a wooden dowel; add water to your kettle in whatever increment you'd like (half gallon at a time if you wish), just remember to heat the water as you go.  Use a hacksaw or permanent marker (on the dowel) to make a few marks; half gallon, one gallon, one and a half gallon...  use a tape measure and a little math to measure out the rest of the marks.  Now when you've finished your runoff place the dowel into your kettle to see your fill volume.
Title: Re: Mash efficiency
Post by: timmyr on October 18, 2010, 12:37:47 PM
Quote
Well guys, I finally ordered a sight guage for my HLT,

What did you order?  I am thinking about putting a site gage on my HLT and MT.
Title: Re: Mash efficiency
Post by: micsager on October 18, 2010, 04:10:55 PM
Quote
Well guys, I finally ordered a sight guage for my HLT,

What did you order?  I am thinking about putting a site gage on my HLT and MT.

Weldless Sight Gauge, 16" 6693

From www.midwestsupplies.com
Title: Re: Mash efficiency
Post by: richardt on October 18, 2010, 04:40:08 PM
Experience has taught me that using a sharpie to make markings on a long plastic mash spoon does not leave a permanent mark.
I suspect the heat and the acidity of the wort and/or StarSan solution dissolves it off within one brew day.

I'd suggest the "notching" idea mentioned earlier.
e.g., Dremel tool or the back of a heated metal dinner knife (wear gloves) to melt a "notch."

If anyone knows a marking pen that stands up to acidic environments, please let us know.
Title: Re: Mash efficiency
Post by: a10t2 on October 18, 2010, 07:27:55 PM
If anyone knows a marking pen that stands up to acidic environments, please let us know.

Nail polish lasts much longer, and when it does go it tends to flake, so it's easy to separate it from the beer along with the trub.
Title: Re: Mash efficiency
Post by: jaybeerman on October 19, 2010, 02:51:31 AM
Experience has taught me that using a sharpie to make markings on a long plastic mash spoon does not leave a permanent mark.
I suspect the heat and the acidity of the wort and/or StarSan solution dissolves it off within one brew day.

I'd suggest the "notching" idea mentioned earlier.
e.g., Dremel tool or the back of a heated metal dinner knife (wear gloves) to melt a "notch."

If anyone knows a marking pen that stands up to acidic environments, please let us know.

If you're using anything other than a wooden dowel use a notch.  I will say that 9 years ago +/-  I marked a wooden dowel with an "Ideal Mark" black marker, they're made for land surveyors, and most of the marks are still there.  Cheers, j
Title: Re: Mash efficiency
Post by: Mikey on October 19, 2010, 03:45:25 AM
I use a piece of 1/2" X 1/8"  aluminum bar stock and stamp the levels. They're not going away.

FWIW you can get metal stamping sets from Harbor Freight for cheap.
Title: Re: Mash efficiency
Post by: gordonstrong on October 19, 2010, 11:48:46 AM
I think you're missing the most obvious solution.  Why are you sticking your volume measuring device into the wort?  Why not measure from a fixed point on the top of the tun?  You still calibrate it the same way, but you don't have to immerse anything.
Title: Re: Mash efficiency
Post by: jeffy on October 19, 2010, 12:12:04 PM
I think you're missing the most obvious solution.  Why are you sticking your volume measuring device into the wort?  Why not measure from a fixed point on the top of the tun?  You still calibrate it the same way, but you don't have to immerse anything.
That's thinking outside the box, err kettle.  I like it.
Title: Re: Mash efficiency
Post by: hopfenundmalz on October 19, 2010, 01:16:10 PM
I think you're missing the most obvious solution.  Why are you sticking your volume measuring device into the wort?  Why not measure from a fixed point on the top of the tun?  You still calibrate it the same way, but you don't have to immerse anything.

That's they way I do it.  Seemed obvious the first time.
Title: Re: Mash efficiency
Post by: timmyr on October 23, 2010, 12:53:25 PM
I think you're missing the most obvious solution.  Why are you sticking your volume measuring device into the wort?  Why not measure from a fixed point on the top of the tun?  You still calibrate it the same way, but you don't have to immerse anything.

+1, I had a metal yardstick that no longer has all the markings...now I measure from the top and plug into a spreadsheet to do the hard math.  However, I recently upgraded to a Blichmann 20-gallon boil kettle and now REALLY want site gages on my other two vessels...looking the the MB site gages for my 26-gallon HLT and 15-gallon MT.