Grain crushing -- size

mr_beer

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Does it matter if the grain is crushed fairly fine -- .010 or so.

Since there is no sparge with this method, aside from slow drain of the bag, my sense is that the finer grind will result in improved efficiency because more surface area being exposed.

My grinder is set for that fine grind and I would rather not change its settings.

Comments and opinions are solicited.
 
The problem with milling that fine is that you'll be milling the husks and extracting tannins. I really don't think you'll see much difference in extraction once you mill finer than about.020 to .025".
 
Great factual answer -- something I had not considered.

Tannin extraction would certainly affect the flavor.

I am using a 'crusher' set up for distilling -- grinds stuff to almost powder. Not good for this type of mash preparation as you pointed out.

Thanks for the answer. Have a good weekend.
 
Also if you go too fine you will actually get a lot of grain pieces in the wort. In a normal crush with a dual roller mill, the grain husks act as a filter bed for the grains, and this is true even for BIAB where you are merely lifting the grains out at the end of the mash. This helps reduce the cloudiness in the wort and aids overall beer clarity (as does recirculation which many BIAB systems have).
 
Great factual answer -- something I had not considered.

Tannin extraction would certainly affect the flavor.

I am using a 'crusher' set up for distilling -- grinds stuff to almost powder. Not good for this type of mash preparation as you pointed out.

Thanks for the answer. Have a good weekend.

I don't often disagree with BOB357 but tannin extraction is less from too fine a crush and more to do with too high of a mash PH.

Mash conversion can suffer with too coarse of a mash so you might think it would improve the finer the crush when in actuality there is a point of diminishing returns.

Everyone's system is different with various false bottoms, homemade mash manifolds, different malt pipes in all-in-one units or different brands of BIAB bags The common rule of thumb used to be to start at .030 and see how that goes... for the next brew dial that down to .025 and so on until you get the efficiency you want without getting so fine that you risk a stuck sparge.

Another rule of thumb for those without a feeler gauge is to set the rollers to a point where the malt kernels are broken into three or four pieces but the husks are still intact and begin adjusting downward from there until you dial it in the way you want. Its a lot of trial and error but you will end up with the crush that works for you and your process.
 
Well, let me expand a bit. Everyone making beer uses a two or three roller roller mill. Works fine for softer grains like barley. Use on denser grains like corn or rice will quickly ruin your roller mill.

I purchased an actual 'grinder'. eBay has them -- "Electric Grain Mill Grinder Corn Wheat Feed Flour Cereal Grinding Machine 110V"
It will grind everything and is substantially more durable than a roller mill.

I sold my roller mill because I did not need two items that do the same thing.

Adjusting the coarseness of the grind is not scientific -- fiddle with an adjustment setting and then observe the results. As I currently have it set, the results are just a skosh coarser than flour.

I use a 200 micron BIAB item for beer -- pretty fine but certainly it would allow some finer pieces through. No issue with stuck sparge.

My sense is that I will have to make the grind coarser -- Brad provided a reason (clarity) and there might be an issue tannin extraction.

I will experiment to determine if I can see malt kernels are broken into three or four pieces.

Thanks again to all who took the time to respond.






 
I don't often disagree with BOB357 but tannin extraction is less from too fine a crush and more to do with too high of a mash PH.

Mash conversion can suffer with too coarse of a mash so you might think it would improve the finer the crush when in actuality there is a point of diminishing returns.

Everyone's system is different with various false bottoms, homemade mash manifolds, different malt pipes in all-in-one units or different brands of BIAB bags The common rule of thumb used to be to start at .030 and see how that goes... for the next brew dial that down to .025 and so on until you get the efficiency you want without getting so fine that you risk a stuck sparge.

Another rule of thumb for those without a feeler gauge is to set the rollers to a point where the malt kernels are broken into three or four pieces but the husks are still intact and begin adjusting downward from there until you dial it in the way you want. Its a lot of trial and error but you will end up with the crush that works for you and your process.
We're on the same page @Kevin58.

I agree 100% that tannin extraction is much less likely to be caused by too fine of a crush than by too high of a mash PH, as long your crush is within a range where the husks remain relatively intact, as is normal when brewing beer. Once you approach a point where the husks are being pulverized, you will be much more likely to extract tannins. IMHO, setting most mills to .010" will produce a crush that's, at very least, approaching that point.
 
I have been reading where others are pre conditioning the grain before milling, This lets the husk get a little tougher and remain more in tact while reducing the crush size. Any experience here doing this and is it worth the extra time and effort? how would this affect the Tannin extraction or would it have any effect?
 
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Well, I might have some better info in a couple of weeks.

I have a favorite recipe -- a highly hopped IPA style with higher ABV. I have used it many time over the past decade.

By accident I 'crushed' or milled my grains to a fairly fine amount -- probably in the .010 area. I elected to continue.
Then I blew past my target temp for steeping -- up to 180.
Rather than discard the wort I went ahead and it is now dry hopping and will be bottled in a week or so.

At that point I will be able to determine if it tannin extraction materially affects this recipe. Sort of an interesting (unintended) experiment.

Will report back regarding the taste -- specifically the bitterness.
 
I have been reading where others are pre conditioning the grain before milling, This lets the husk get a little tougher and remain more in tact while reducing the crush size. Any experience here doing this and is it worth the extra time and effort? how would this affect the Tannin extraction or would it have any effect?
Like many things in homebrewing if you find value in doing it then by all means continue. As in any hobby each participant goes about things a bit differently. For some, that process becomes part of the enjoyment. For me however I find wet conditioning grain before milling one of many things in homebrewing that simply take up my time and give me little or no benefit in return. Imo if you are using a basket or bag in your system then there should be little or no concern about how fine you crush and whether husks remain intact or not.
 
Wouldn't an iodine test tell you if your crush was good enough? it would seem that if all the starch has been converted, then grinding any finer would only increase the chance of bad things happening. i.e., no upside.

-pat
 
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