Can too fine of a crush hurt efficiency?

[e lo]

I had a distressingly low efficiency this weekend (~50%) for reasons that are unclear. I usually hit 70-75%. I crushed the grains at my LHBS with a MaltMill they have available for customer use. I set it to the finest setting, which is what I've done in the past. However, I've never done an AG wheat beer before, which this was (a weisenbock.) Is it possible that my crush was too fine, and this hurt my efficiency?I would think that the finer the crush, the better the efficiency, and that the only limiting factor on crush would be potential stuck sparges. Is that wrong?

There seemed to be a fair amount of flour after the crush, and while the wort cleared of larger hull pieces within a cuople of quarts of vorlauff, it stayed cloudier than I was expecting. Maybe that's due to the wheat; I don't really know.

Grain bill was 8 lbs wheat malt (Germany), 4 lbs Pils (Germany) and .5 lb Crystal 60L; mash tun is a 60 qt IceCube cooler with stainless steel braid loop. Mash was a single step at 155 for 1 hour. Sparge was a double batch sparge.

 

[Bobby_M]

What was your post boil OG and how much made it into the ferementer?

 

[cubbies]

One thing that would concern me with too fine of a crush would be dough balls. Seems like you could get those pretty easy if you had a bunch of flour.

 

[clayof2day]

I used to use the same mill and always noted lower eff. in my wheat beers. I think the lack of husks and smaller kernels actually requires a finer crush than what you can get on that mill, at least for the wheat. Those little suckers are hard to crush!

On another note, you're the second person I've heard say that that mill is adjustable, but I never figured out how to adjust it. Maybe I'm dim, but I didn't think it was adjustable. Good luck!

Matt

 

[BierMuncher]

...Grain bill was 8 lbs wheat malt (Germany), 4 lbs Pils (Germany) and .5 lb Crystal 60L; mash tun is a 60 qt IceCube cooler with stainless steel braid loop. Mash was a single step at 155 for 1 hour. Sparge was a double batch sparge.

I usually will mill my wheat malt separately and run it through twice. Unlike barley, it may not be sufficient to simply crack the hull. Wheat malt seems to be a solid “seed” if you will and cracking it several times seems to expose more of the “meat”.

If you had a very fine crush...I’d tend to agree that dough balls can be an elusive culprit. I have to stir the **** out of my mash and even after 2-3 minutes, I still seem to b breaking up dry clumps of grain. With such a sever loss of efficiency, I’d look to that as the problem.

 

[Drunkensatyr]

What it looks like to me is low enzyme. Wheat is a bit harder to convert. Did you check for starch conversion?

 

[e lo]

Bobby -- post-boil OG was 1.051; ~4.75 gallons into fermenter, leaving about a quart and a half in the kettle with break/hop sludge. Was expecting more like 1.066 with that bill and my usual efficiency.

cubbies -- Yeah, I was really careful to avoid dough balls when mashing in, because I thought the wheat would make everything gummy. I added ~ 1/4 of the water + 1/4 of the grain, stirred very well, then repeated until it was all in. I'm reasonably certain I had a well-mixed mash. Thickness was 1.25 qts/lb.

Matt and Bier -- that's a good point about the wheat probably needing a different/more aggressive crush. I can't actually say how well the wheat was crushed. I ran it though first, and didn't stop to examine it before I crushed the pils and crystal on top of it, which is probably where the flour came from. I should have paid more attention to the crush of the wheat, but SWMBO was with me at the brew shop, and she was anxious to get home, so I wasn't as careful as I should have been. Matt, to adjust it, you have to loosen the thumbscrews on the edges of the sideplates. Then you can turn the adjustment knobs and re-tighten the thumbscrews. I don't know much about the JSP line, though -- maybe there are both adjustable and non-adjustable MaltMills.

Satyr -- no, I didn't. I know I should have; I guess I'll start!

Thanks for the input, guys. Maybe this will move me a step closer to getting a mill of my own...

 

[david_42]

Probably a crush problem with the wheat as stated earlier. Wheat, even malted wheat, is tough & the kernels are small. The setting that will properly crush wheat will turn barley into flour. Malted wheat has plenty of enzymes, so that isn't the problem.

One question, the wheat malt was German. Is it fully converted? Many European malts are not, this gives the brewer more control over the mash. Wheat malts frequently require a protein rest, if not fully converted.

 

[e lo]

David, that's another good point. It was from Durst -- I'm not sure what the answer is to your question, though. You said fully converted -- did you mean fully modified, or am I misunderstanding the question?

I found this in reference to Durstmalz, which leads me to believe that their wheat malt is not fully modified, so I should have used a protein rest (something I considered, but chose not to do in the spirit of KISS) : "Wheat: Because the company believes that an intensive malting process should be avoided with wheat, it gives preference to wheat varieties that show low protein modification and low viscosity (Borenos, Atlantis, and Tambor)."

 

[modenacart]

like to measure the volume and gravity of my wort just after mashing, before adding anything to the wort, ie, sugar, water, ect, for the efficiency measurement. I feel it gives me a more accurate reading.