Trouble with Efficiency

I would hazard a guess that many people who have low-ish mash efficiency with fly sparging are getting some degree of channeling in their runoff. Channeling causes the runoff to be a higher proportion of sparge water to wort and leaves behind pockets of undiluted/less-diluted wort in the grain bed. And it my not be obvious that it's happening.

Batch sparging/No-Sparging makes channeling irrelevant, because the wort is homogenous. You can still get pooling (like a localized stuck lauter), but in that case, it's obvious and can be easily fixed: re-stir, vorlauf, run-off.

 

Yes, that is my thought also. But I almost always do a mashout which in effect is a mini-batch sparge. I'm pretty slow in the sparge process and the grain bed has the appearance of being well-formed. Plus, my efficiency is pretty damn consistent. That said, channeling is the most likely culprit.

Anyone else crushing as low as 0.034 inches?

 

I double batch sparge on most of my normal brews and get 80-85% most times. Fly sparging would get a few more points but not worth the effort. Big beers I don't have enough sparge water to do a double sparge so I drop 10 to 15% on those.

If you are fly sparging and crushing your own grain, you should be getting in the 80s. Is there a lot of dead-space under your false bottom? Are you mixing the grains well enough to get rid of dough balls? Are you sure everything is calibrated (PH meter, thermometer)?

 

Minimal deadspace ... aggressive stirring, good mix ... positive thermometer(s) are accurate, ph is computed (software) and measured (econ ph meter).

Where do you set your mill crush?

 

I don't measure my gap, but it's pretty tight. I'd say I get about 20% flour, 5% barely cracked, and 75% of the kernels broken into about 6 small pieces each. Husks remain mostly intact.

 

I find it interesting that this discussion seems to be centered around peak efficiency (maybe that is just the way I read it). To me, repeatability and consistency are more important goals.
I'm working on that.

 

Usually about .0375 for most grains. .03 or so for harder wheat malts. I don't know a lot about fly sparging so Vikeman is probably right about channeling. Have you tried batch sparging to compare?

True that! If you're getting over 70% your not saving a whole lot more money by getting more. I only started looking into more efficiency after mine started dropping to 60 and a couple below that after hitting 70s for a number of batches. After getting my own mill, it shot right back up (and then some!) so figure the issue had to be the LHBS widened the crush gap plus the fact I wasn't crushing right before brewing.

 

Excellent point. If you can reach your destination right on the money every time, that's the place to be.

Cheers.

 

I regularly get 82% but I grind super-fine and do BIAB. My first batches with my mill were 82% so I just never changed anything.

 

My two-roller Monster Mill is set to a gap of 0.035". I fly sparge (30 - 40 minutes, typically) and regularly get above 80% efficiency for a standard 5 to 6% beer. Sometimes the efficiency pushes 90% (as in a recent beer with highly enzymatic Briess Pils malt). BTW, I typically use 5 gallons of water for the mash and 4.5 gallons of sparge water. My mash thickness is typically 1.8 quarts / lb of grain. Cheers!

 

Sparging three times instead of two times, and switching from a 60 to a 90 min boil has increased my efficiency by 15-20 points on average. It sucks cause it takes a little more time to do that last sparge and the extra 30 min of boil time, but on the flip side I buy and use less grain now to get my desired outcomes. Something you may want to consider to increase your efficiency