Mash Efficiency- what is it?

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catdaddy66

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After deciding to work towards an all grain set up I have read many posts and articles that state it is desireable to achieve 70% or greater 'mash efficiency'. At first I thought this referred to the percentage of available starches converted to useable, fermentable sugars by the enzyme action during mashing. But now I am a bit confused... Further reading gave indications that efficiency was related to the amount of wort collected from the mash tun.

I am sure it's one or the other. Anyone? Thanks!
 
From my understanding, the efficiency is how many fermentables you pull out compared to the maximum theoretical amount.

It does have to do with how much wort pulled from the tun in that the more water you use to sparge with the more sugars you will pull out. There is a point where you can balance the maximum sugar extraction via sparge with a certain amount of sparge water. i have been told the magical amount is between 4 and 7 gallons of sparge water, depending on the recipe. I know I have not sparged enough and was rewarded with a low efficiency.

All that said, I have yet to find my magical balance, so feel free to take my advice with a grain of salt.
 
Everything you put in has an amount of sugar it should contribute to the gravity. Efficiency is a measure of how many of those sugars you were able to pull out. For example: if the combined sugar available could have given you a gravity of 1.040, 100% efficiency would give you 1.040 original gravity. A 65% efficiency would give you a gravity of 1.026.

A low efficiency can be a problem requiring you to use more grain to hit your target.

For example my efficiency runs between 73 and 78%. If I want a wort of 1.050 then I need to use enough grain to provide around 1.068.
 
Is this reading before the boil? And if so I assume u need to adjust the reading due to high temp? Or do u let a bit cool down n test cylinder?
 
The reading is taken after the mash and before the boil. However, at that point the sugar stays the same and you just boil off water, unless you add some other sugar in the kettle--like Candi Sugar.

This pre-boil reading is to check your efficiency.

From it you can calculate what your post-boil gravity will be. If you pull 7.5 gallons of 1.040 wort and boil it down to 5 gallons, you have only lost water so the new gravity will be 1.060. It is this reading that you use to calculate alcohol with the final, post fermentation gravity.
 
As for the temperature, let it cool down or you have to use a calculation to adjust for temperature. I use a refractometer with automatic temperature compensation. This lets me check my gravity at any point I want with only a few drops of wort and don't need to cool it.
 
Keep in mind that there are a couple efficiencies. Brewhouse and mash (and probably some more). Mash measures conversion of starch to sugar. But honestly the important one IMO for a homebrewer is brewhouse. It takes into account mash efficiency as well as any volume losses in your system (i.e. mash tun dead space, etc.)
 
pabloj13 said:
Keep in mind that there are a couple efficiencies. Brewhouse and mash (and probably some more). Mash measures conversion of starch to sugar. But honestly the important one IMO for a homebrewer is brewhouse. It takes into account mash efficiency as well as any volume losses in your system (i.e. mash tun dead space, etc.)

Brewhouse efficiency is important. However you can't improve what comes out of the end until you have good efficiency coming in the front.

One point though "mash efficiency" is a measure of sugars extracted. It takes into account conversion. You can have low efficiency because of a bad conversion or because you failed to extract everything that you did convert. PH and temperature impacts one, sparging method, speed and temperature impact the other.
 
Brewhouse efficiency is important. However you can't improve what comes out of the end until you have good efficiency coming in the front.

One point though "mash efficiency" is a measure of sugars extracted. It takes into account conversion. You can have low efficiency because of a bad conversion or because you failed to extract everything that you did convert. PH and temperature impacts one, sparging method, speed and temperature impact the other.

Oh, I agree. When troubleshooting, starting with mash efficiency is the way to go. But in the end BH efficiency is where it's at. :mug:
 
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