How can I improve my mash efficiency?

The fastest sparge impedes the sugar escape route via excessive grain bed compaction. A slower sparge encourages a more porous grain bed and a slightly more efficient extraction of sugar. These are indisputable FACTS envisioned and verified by Brew_Betty via rigorously controlled xBeerImentz.

The good news for the fast sparge camp is a slow sparge doesn't make a big difference. However, it is practically guaranteed to be 1.21-2.24 points mo' better!

Failure to duplicate these results indicates my sparging skill and / or the efficiency of my proprietary lauter apparatus is superior to yours.

 

a discarded drink straw from McDonalds?

 

Another way to improve efficiency is a double batch sparge. Basically divide your normal sparge water in half and sparge twice.

 

That would produce off flavors and wouldn't lauter at all.

 

No. With fly sparging, the runoff gravity is not constant, and the gravity within the lauter tun is not homogeneous. You have to be careful not to make a channel that allows the sparge water to cut through and drain before mixing thoroughly with the rest of the wort. With batch sparging, the wort (and its gravity) in the tun is homogenous after stirring. Exit path doesn't matter, as long as the sparge doesn't get stuck/leave puddles. OTOH, fast fly sparging can cause weak wort to drain while strong wort stays behind.

Yes, with batch, if the bed compacts to the point that less volume escapes, that would affect mash efficiency. I would consider that to be a form of stuck sparge, though maybe not obvious. Allow me to quote myself, with added bold text...

If you do not acknowledge this, I will quote myself again, but without direct attribution so as to make it seem like someone else said it, and with italics added.

That certainly improves mash efficiency vs single batch. I once modeled the process, and it turns out, IIRC, that the most efficient multi-sparge strategy is where the runoff volume in each step is exactly equal.

 

curious, then. any data about the contact time of water with grain in order to have an efficient sparge?

 

That's a pretty weak crush. Looks like quite a few grains are completely intact. I would either adjust the mill's gap. Or if they won't let you do that, run them through again.

 

That is a good example of an LHBS crush that will produce lower efficiency. The white parts should be mostly the size of coffee grounds.

 

Well, he won't have a stuck mash with his false bottom.

 

That kind of crush is a big part of your issue. Definitely run it through again.