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General Category => Extract/Partial Mash Brewing => Topic started by: shaggywhodey on July 04, 2011, 11:07:22 PM

Title: Mash efficiency using LME?
Post by: shaggywhodey on July 04, 2011, 11:07:22 PM
Trying to calculate my mash efficiency for a hefeweizen extract recipe.  Reading "Designing Great Beers" and using it's table to calculate.  Ray Daniels has liquid extract potential as 1.037-1.039.  Wouldn't this drastically change with different LME's?  I used a wheat LME that's 65% wheat extract and 35% barley LME (pilsner I think?).  Also steeped 1lb. Munich.  Here's my calculations:

1lb Munich=1.035=35GU
6.5lbs. LME=1.038=(38x6.5)=247GU
Total=(247+35)=282GU potential gravity of grains

My OG was 1.059 at 5.5 gallons.  So 59x5.5=325 total gravity of wort

With this I end up with (325/282)=1.15 or 115% efficiency which is obviously incorrect.  Can anyone tell me where I went wrong?
Title: Re: Mash efficiency using LME?
Post by: dbeechum on July 04, 2011, 11:32:33 PM
Usually with extract batches if you have abnormally high or abnormally low gravities it's due to incomplete mixing of the concentrated wort into the chilled water.

The gravity contributions will change with manufacturer and type, but not that significantly.
Title: Re: Mash efficiency using LME?
Post by: stlaleman on July 04, 2011, 11:57:14 PM
And or inaccurate volume measurement.
Title: Re: Mash efficiency using LME?
Post by: tschmidlin on July 05, 2011, 08:44:57 AM
You steeped Munich?  At what temp and for how long?  Munich should be mashed.
Title: Re: Mash efficiency using LME?
Post by: Jimmy K on July 05, 2011, 12:58:54 PM
You're right on with the brewing and measuring, just not the calculations. I put 6.5 lbs LME + 1lb munich into my brewing software and got a predicted OG of 1.062. 6.5lbs LME alone gives a predicted OG of 1.057. You're right in the middle.

Unless you really love doing the calculations by hand, I'd recommend using brewing software.  I like Beersmith which is under $30. I also used to use www.beertools.com where you can get a free account with slightly limited, but still useful, functionality.
Title: Re: Mash efficiency using LME?
Post by: Hokerer on July 05, 2011, 02:59:37 PM
And just to be clear, since this is using extract, we're really talking about "brewhouse efficiency" and not "mash efficiency", right?
Title: Re: Mash efficiency using LME?
Post by: shaggywhodey on July 05, 2011, 11:56:28 PM
I steeped the Munich at 150 for an hour.  I don't have a mash tun yet.  @Mtnrck, thanks for the website, I'll use it.
Title: Re: Mash efficiency using LME?
Post by: tschmidlin on July 06, 2011, 12:17:57 AM
I steeped the Munich at 150 for an hour.  I don't have a mash tun yet.  @Mtnrck, thanks for the website, I'll use it.
Ok, cool.  That's called mashing, not steeping ;)
Title: Re: Mash efficiency using LME?
Post by: gordonstrong on July 06, 2011, 09:15:55 PM
Depends on the ratio of water to grain.  If it's the full volume of strike water, it's steeping...
Title: Re: Mash efficiency using LME?
Post by: tschmidlin on July 06, 2011, 09:22:51 PM
I guess it would depend on your water and where the pH balances out.  As long as you're still getting conversion I would call it mashing.
Title: Re: Mash efficiency using LME?
Post by: Joe Sr. on July 06, 2011, 09:49:26 PM
I agree.  If it was at 150 for an hour, I'd call it mashing, too. 

Efficiency doesn't really matter, since you're fermentables are coming from the extract, but that's more than a steep.
Title: Re: Mash efficiency using LME?
Post by: afacini on July 08, 2011, 07:59:02 PM
This is actually something I was about to ask... probably close enough to not be its own thread.

So a lot of recipe analyzers (e.g. BeerTools) ask for your mash efficiency to calculate tons more data. As a partial mash & extract brewer, how does one accurately figure that out?

If, for example, I mash some amount of 2-row and crystal malts for 30 minutes, but am not very confident the temperature was accurate for what I wanted (too hot, too slow, etc), what should I do? This particular recipe was 4lbs grain, 3.2lbs LME.

BeerTools sets a default for partial mash recipes at 70%, and for someone still fighting a stovetop burner to get things right, how should I adjust?
Title: Re: Mash efficiency using LME?
Post by: tschmidlin on July 09, 2011, 05:34:42 AM
You efficiency for any extract and sugar should be 100%.  It is automatically set to that in BeerSmith, regardless of the manual setting.  That should be the case for any brewing software.
Title: Re: Mash efficiency using LME?
Post by: a10t2 on July 09, 2011, 02:14:05 PM
So a lot of recipe analyzers (e.g. BeerTools) ask for your mash efficiency to calculate tons more data. As a partial mash & extract brewer, how does one accurately figure that out?

Take gravity and volume readings after the mash/sparge, but before adding any extract or additional water. That's all you need to calculate efficiency. You can do a weighted average of the grist to get a more accurate answer, but assuming the mash is mostly base malt this will be pretty close:

Eff = 1000*V*(SG - 1)/(36*W)

Where V is the wort volume in gal and W is the grist weight in lb.
Title: Re: Mash efficiency using LME?
Post by: Joe Sr. on July 09, 2011, 02:39:53 PM
After a few batches you should have an idea of your mini-mash efficiency.

You can always adjust your dme or sugar to hit your target after your gravity readings.