Mash Efficiency vs Total Efficiency

I use Beersmith to make my recipes. I made an imperial stout yesterday and my measured mash efficiency was 80%, but my brewhouse or total efficiency was on 65%. How did I lose 15% and is there a way to increase my total efficiency without increasing my mash efficiency?

The large amount of grain in the mashtun is holding a proportionately larger volume of wort than in a typical mash, so if you want to keep your efficiency in the normal range, you can run a little more water through the grain and then boil off the excess. I’d rather just accept the lower efficiency and add some more grain to compensate. But you also mention a mash efficiency of only 80% - you should be able to achieve 100% conversion, so you might want to look at your crush and your mash pH, see if there’s an easy fix.

According to John Palmer in a Brew Strong podcast the sweet spot for mash efficiency is 75%. The higher you go above 75% the more husk flavor and tannins you get out of the grains. I’ve considered a more coarse crush to lower my mash efficiency. I will test your info out on my next brew. I will use a bigger pot to collect more runnings and go with a longer boil

[quote=“kjhebert10”]According to John Palmer in a Brew Strong podcast the sweet spot for mash efficiency is 75%. The higher you go above 75% the more husk flavor and tannins you get out of the grains.[/quote]Perhaps there’s a misunderstanding on “mash efficiency” - to me this means the % conversion, which should be close to 100%, but maybe you’re meaning the mash plus the lauter efficiency, which is typically in the 70-90% range, a measure of how much potential sugar ends up in the kettle. For big beers, it’ll drop lower unless you compensate as I posted already, or you can do a partigyle with the first runnings going for a really big beer and the second for a smaller (this is a traditional way to maximize the efficiency).

Yes, I believe Beersmith uses pre-boil volume and pre-boil gravity measurements to calculate “mash efficiency.”

I don’t think you need to worry about this if pH and temps are where they should be.