Mash efficiency question.

[BlackSailJ]

Do you see a difference in sugar mash efficiency when fermenting on the grain vs off the grain?

When brewing beer I use my mash tun to separate the sugary wort to boil then ferment it. I know that my mash system is pretty consistent at 82% extraction, leaving a sg of around 1.008-1.012 remaining in the malted grains depending on the run. If I use the same recipe using 100% malted barley and leave it in fermenter, oppose to removing it, should I expect to see a higher mash efficiency rate because the yeast has access to all the sugars? Shouldn't the mash efficiency be 100% if all the enzymes and temperatures were done correctly?

[still_stirrin]

... Shouldn't the mash efficiency be 100% if all the enzymes and temperatures were done correctly?

It would if you could get all the liquid out of the grains when done fermenting. But you won't. You'll get them quite pastey, but not dry. So, you will lose some efficiency during this process.

Fact is...it is impossible to get 100% efficiency. You can get close (above 90%), but unlikely you could get 100%...unless you actually stripped the mash "on the grain". Then, you could see higher (approaching 100%) extract efficiency.
ss

[BlackSailJ]

Ok, that does make sense. Then I guess it is best if I left my mash efficiency at ~80% for all my recipe formulations.

[still_stirrin]

Actually, 80% extract efficiency is very good for a lautering system, which I assume you're doing.

I lauter my mashes as well and I'm down around 72-75% extract efficiency. But it is predictable, so I simply adjust the recipe calculator to compensate and I'm good to go.

Old grains can screw up the reliability and variations of extract potential from malt house to malt house will as well.

The grains are relatively inexpensive and I prefer quality over quantity. So, I don't need to get to 100% efficiency...like I ever could! And I don't like to water down an all grain product with sugar...it steals from the flavors.

Consistant results from a predictable recipe and process are the key to success...not how much it costs or how much I leave behind in the fermenter. But...YMMV.
ss