Efficiency Mini Test

Based on my last brew with my new mill(est. OG was 1.069, measured was 1.046), I wanted to explore setting a finer crush. These results were a 47.8% efficiency.

Is there a “mini efficiency” test I can do with say a pound or two of grain, do a mash and run the measurements? I suppose like a mini brew day that stops after the sparge.

I know this is time consuming, but seems less of a loss than doing a 5 gallon to completion and getting poor results.

*The above results were based on a 13.32 pounds of grain on a 5 gallon batch.

I would bet that your crush is not solely to blame here.  What was your mash temp? How do you sparge?  Fly, batch? Most likely you did not rinse the grains enough to get more sugars out.

My process hasn’t changed. Batch sparge, 152 or so mash for an hour, sparged around 175.

wow Justin…something happened for sure. that low, you would have had to barley even crush grain at all. did you observe the crush at all?

Which mill did you purchase and what factory gap setting did it come set to?

+1 to always checking the crush prior to doughing in.

I did, seemed fine to me. However, I am no expert at judging what a good crush looks like.

MM2 Pro, .045"

You know, I do recall not stirring the mash very much. I ended up hitting the mash temp right away after transferring the strike water. Maybe I didn’t stir enough? I know there weren’t dough balls though.

Back to my Q, mini efficiency test?

I am sure you could brew some small batches (1G-ish) to check efficiency trends but the actual efficiency from the small batches would not likely match your 5G efficiency since the equipment and methods would be different.

You can do mini mashes. Covered in a May/June Zymurgy article by Agatha Feltus.

I tested my 2 gal Coleman stacker mash tun with 4-5 test mashes. Measured efficiency and dumped then afterward.

This makes me very sad. You still had wort that wanted to be beer.

If you did 1-2 gallon batches using the same mash tun, it shouldn’t be, right?

My thought is that there are only a few variables and you should be able to get close enough by being careful right away and it doesn’t need to be perfect:.
I would do this: calibrate your thermometer, use brun water to get ph in range, mill your malt until your scared then run through again (stuck sparges and tannin extraction are bogeymen few of us have seen face to face), stir the heck out of your mash, keep boiling water and ice cubes ready so you can quickly adjust mash temp, make sure temp and time is right. Also keep some light dame on hand. You will take a few times to dial it in but you’ll have beer.

Light DME, not “dame”. Not the first time auto correct has made me look like an awful person.

Good advice. Everybody has to dial in their system at first. Crushing your own malt is great but takes a little time to dial in what to expect there as well. Might as well have some beer for the effort.

Edit -  Also, Justin - on the 1.069 ‘expected OG’, was that based on the efficiency you’d been getting prior or just a software number ?

:-.

They were very small volumes of grain. 1lb. Pale and 1lb. Pils each time. I felt terrible but alas I got to test out my equipment!

In addition to dialing in your system with the test mashes, the “crush your grain until you’re scared” comment is not only funny, it’s true.  My initial gap setting from the factory with my Barley Crusher was .039", I’ve dialed it down to .035". I can probably go finer, but I’m happy with the results.  On my system that took me from 65% to around 70% efficiency. I also mash at 1.75 quarts of water per pound of grain.  That works well for my Blichmann kettle and false bottom.  Lauter speed is good, and I haven’t ever gotten a stuck sparge (well, that one time when I used 20% rye and the mash turned into cement  :o).

OK, so did a mini mash tonight…and changed my mill gap setting to .035" (.88m guitar pic, don’t judge me).

2 gallon batch (specs. below). I hit my pre-boil OG on the nose. I dumped almost all of the wort except a small sample tube worth.

Is there any point in boiling this and testing post-boil OG? Shouldn’t they be in line given a normal boil?

2 gallon batch, 3 pounds 2-Row
1.670 mash thickness (1.25 gallons strike, 2.58 gallons sparge)
Mashed at 150, sparged at 180
Pre-boil OG est.-1.025 (hit 1.025)

No need to boil in this case. As long as your volumes are accurate and boil off rate fairly consistent, the postboil reading would be the same differential higher as it would normally be.