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Grind = Crazy Efficiency

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thirstypanda

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Abbotsford, BC
So I dropped by my trusty LHBS (Goldsteam) and I asked Jason if he could double grind my malts for my BIAB session. He said he had just got new grinding rollers and wasn't sure if that was worthwhile. When he did the initial grind it was CRAZY - definitely no need for a second go around.

Anyway, I'm usually in that 65-75% efficiency range depending on how lazy I am with doing a little sparging. Also for BIAB I get a bit extra base malts but considering I had to make one minor grain adjustment, and was doing a Belgian Wit I decided to stick with the recipe.

Anyway, so I go through the process, sparged like a madman, boiled, etc. etc., tested my OG and....How does 83% grab you???? That's crazy efficient. Not too sure, however, what my Belgian Wit's going to turn out like. Was supposed to be 1.052 according to my adjusted Brewer's Friend recipe, and not 1.061!!!

I'm thinking that if I checked gravity before sparging I would have skipped it altogether.

Live, brew, and learn.
 
I always want higher efficiency, so 83% is very good, I would not worry. I want higher efficiency, in order to actually use smaller grain bills to get the ABV I'm after. I brew with the Grainfather, so cutting down on the recipe is always a good thing.
 
So I dropped by my trusty LHBS (Goldsteam) and I asked Jason if he could double grind my malts for my BIAB session. He said he had just got new grinding rollers and wasn't sure if that was worthwhile. When he did the initial grind it was CRAZY - definitely no need for a second go around.

Anyway, I'm usually in that 65-75% efficiency range depending on how lazy I am with doing a little sparging. Also for BIAB I get a bit extra base malts but considering I had to make one minor grain adjustment, and was doing a Belgian Wit I decided to stick with the recipe.

Anyway, so I go through the process, sparged like a madman, boiled, etc. etc., tested my OG and....How does 83% grab you???? That's crazy efficient. Not too sure, however, what my Belgian Wit's going to turn out like. Was supposed to be 1.052 according to my adjusted Brewer's Friend recipe, and not 1.061!!!

I'm thinking that if I checked gravity before sparging I would have skipped it altogether.

Live, brew, and learn.

Your LHBS gave you a great grind which is definitely an advantage with BIAB. Problem is how "consistent" can you expect this to be in the long run. If you use some pre-milled grains from another source, will they yield the same results?

You had great results with 83% efficiency (is this mash efficiency) and your efforts were rewarded. SO next brew day you get 70% efficiency with grains you have no control over. Your recipes suffer, your OG suffers and your beer suffers. Consistency.

If you have any items on your equipment wish list, may I suggest a grain mill. Doesn't have to be all the bells and whistles....just something that gives repeatable crushes.

I doubt the Wit will suffer with a .009 difference, but I'm sure you had rather be on the money than just "fairly close".

Happy Brewing...good job!!
 
If I could consistenly get between 83 and 85% efficiency, I would be delighted, but as Morrey pointed out, without your own malt mill at home, to really nail that sweet spot you're after, you will probably experience a whole different range of efficiency, when the grains are crushed at a home brew store. Not much you can do, besides asking them to crush finer than usual and for a better efficiency than the norm.

I do that with the shops I order from. Sometimes it is really good ( themaltmiller.co.uk - I got between 81 and 89% efficiency after I asked them to make it finer ) and sometimes it is less good. Usually, I get around 75-77% and that's OK. But I want better.
 
I fail to see how double grinding your malts would do anything for efficiency, if the grain is strong enough to move the mill wheels out of alignment and not grid to the gap setting there is something very wrong with that mill, unless on the second run the gap is being adjusted to something far less nothing would change from the first running.

While I have never brewed in a bag it is my understanding the bag takes the place of the husk filtration variable in a traditional mash tun so your grind for BIAB should be all but flour for maximum efficiency. I think most brew shops set their mills to 4.5mm as its the sweet spot for most brewing rigs, its the fastest they can process your order, and extend the life of their mill as long as possible. However, this gap is still a bit to large for peak efficiency for BIAB. It might be the gap on your LHBS's new mill is tighter on the new mill or the old mill desperately needed replacing as the old rollers were all but polished.

I guess the take away would be, unless it makes you feel better I wouldn't waste your time double milling.
 
I fail to see how double grinding your malts would do anything for efficiency, if the grain is strong enough to move the mill wheels out of alignment and not grid to the gap setting there is something very wrong with that mill, unless on the second run the gap is being adjusted to something far less nothing would change from the first running.

Your viewpoint is very theoretical imo, in practice a second run at the same mill setting definitely produces more crush. The grain bits are not going thru the rollers one bit at a time but rather in mass. One piece may get further fractured against another piece and the roller on the second pass. Additionally the piece may pass between the rollers at a different angle in a longer dimension and be further crushed.

Your thinking a grain mill operates like a sieving operation and not a crushing operation.
 
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Anyway, so I go through the process, sparged like a madman, boiled, etc. etc., tested my OG and....How does 83% grab you???? That's crazy efficient. Not too sure, however, what my Belgian Wit's going to turn out like. Was supposed to be 1.052 according to my adjusted Brewer's Friend recipe, and not 1.061!!!

Not a bad problem to have. I've overshot my OG a few times due to efficient crush. Low to mid 80s isn't terribly unusual once you get the crush just right.

I have my mill's gap set to just under 0.030" which works well for me. No double-crushing needed.
 
I have a Corona style mill like this one. http://www.discounttommy.com/p-189-...er-for-wheat-grains-or-use-as-a-nut-mill.aspx

I haven't gotten below 80% since I bought it and usually my brewhouse efficiency is above 85% which it where I have set my software.
Corona's are cheap and perfect for BIAB. I never got below 80% with mine until recently. My issue was all my beers were all dry no matter what, with higher projected OGs and lower FGs. I recently expanded my gap quite a bit to where I think I have the perfect fit for a fine enough crush, but I'm still able to manipulate the body of the beer.
 
I also highly recommend getting your own mill. I was fortunate to get good results from both Ritebrew and AtlanticBrewSupply and using their double milled option when ordering, always around 75-77% mash eff. But I wanted to start buying unmilled grain in bulk so I got a corona style mill, mounted it in a bucket and put a drill on it to motorize it. I am now consistently getting 83-84% eff. and Ive cranked down the plates and got 89% on a sweet stout I did, but I have backed off back to the 84% setting.
 
I fail to see how double grinding your malts would do anything for efficiency, if the grain is strong enough to move the mill wheels out of alignment and not grid to the gap setting there is something very wrong with that mill, unless on the second run the gap is being adjusted to something far less nothing would change from the first running.

.

I agree. Double crushing never had a significant effect on my efficiency. Buying a grain mill had a tremendous effect. Brulosophy had a podcast regarding grain crush and if I remember correctly they were not impressed with double crushing either.
 
I agree. Double crushing never had a significant effect on my efficiency. Buying a grain mill had a tremendous effect. Brulosophy had a podcast regarding grain crush and if I remember correctly they were not impressed with double crushing either.

I do not agree. I have double crushed a few times. I use a Corona style and the second run through pretty much made flour. I got a lot higher efficiency. I also, almost, had stuck sparges on those so I don't do that anymore. I think it depends more on the particular mill, some will do more with a second pass than others depending on setup and wear.
 
I do not agree. I have double crushed a few times. I use a Corona style and the second run through pretty much made flour. I got a lot higher efficiency. I also, almost, had stuck sparges on those so I don't do that anymore. I think it depends more on the particular mill, some will do more with a second pass than others depending on setup and wear.

My results agree that double crushes generally have an impact on efficiency. With BIAB, my system is not likely to have issues like yours, albeit draining can need coaxing. Adding to this, wheat and rye can greatly benefit from a double crush due to the inherent hardness of these grains. I mill wheat and rye separately from barley malts, usually double crushing the wheat and rye, then single crushing the barley. I prefer this method over tinkering with the mill gap.

One small "issue" I note with double grinding is that I have a heck of a time with dough balls when mashing in.
 
I do not agree. I have double crushed a few times. I use a Corona style and the second run through pretty much made flour. I got a lot higher efficiency. I also, almost, had stuck sparges on those so I don't do that anymore. I think it depends more on the particular mill, some will do more with a second pass than others depending on setup and wear.

I should probably clarify that double crushing at the LHBS had no effect but it could now that I have my own mill. I've just never found the need once I bought the mill and got it set to a gap which is a finer crush than the LHBS. I just assumed the LHBS had to set their mill to an average crush that didn't cause a stuck sparge for non-BIAB brewers.
 
I should probably clarify that double crushing at the LHBS had no effect but it could now that I have my own mill. I've just never found the need once I bought the mill and got it set to a gap which is a finer crush than the LHBS. I just assumed the LHBS had to set their mill to an average crush that didn't cause a stuck sparge for non-BIAB brewers.

It seems to me that double crushing at the LHBS who set the gap for the average of all brewers is where you would see the most difference. If you set your own mill to your system you shouldn't have to double mill.

I also never change the setting on my Corona style mill. It is too imprecise to really know what is happening so I tested, checked, adjusted until I got what I was looking for then locked it down. The only time readjusting was after my move from RI to FL. I had partially disassembled it. Like Morrey, I double grind wheat and rye. - usually.
 
Your viewpoint is very theoretical imo, in practice a second run at the same mill setting definitely produces more crush. The grain bits are not going thru the rollers one bit at a time but rather in mass. One piece may get further fractured against another piece and the roller on the second pass. Additionally the piece may pass between the rollers at a different angle in a longer dimension and be further crushed.

Your thinking a grain mill operates like a sieving operation and not a crushing operation.

I try to double crush using my 20 year old JS non-adjustable Maltmill when I do BIAB (using your great bag, thanks!) and I see at least a 5 point OG increase over a single crush BIAB batch.

When I use my 3 vessel system which has a cooler mash tun with bazooka screen filtering I can't double crush without getting a stuck mash in my HERMS coil.

However I recently had the long-overdue idea to put double-crushed grain in my mash cooler inside my BIAB wilserbag and I didn't have a stuck mash and my efficiency went from the typical 75% to 79%. I also had exceedingly clear wort into the kettle with only about 10 minutes of extra time spent double crushing the grain. I only wish I'd thought of this when I first got my BIAB bag months ago.
 
Your viewpoint is very theoretical imo, in practice a second run at the same mill setting definitely produces more crush. The grain bits are not going thru the rollers one bit at a time but rather in mass. One piece may get further fractured against another piece and the roller on the second pass. Additionally the piece may pass between the rollers at a different angle in a longer dimension and be further crushed.

Your thinking a grain mill operates like a sieving operation and not a crushing operation.


I know on my mill the gap is tight enough that 2 pieces of grain could not occupy the same space and the same time and be milled, this will maximize the efficiency but increase the mill time. If the mill gap is so large that 2 or 3 previously milled kernels could fit in the gap than yes, double milling would give you a different result, but why stop there, why not do a triple or quad milling. Every pass through the mill would then in theory increase the efficiency so keep doing it until you have flour but I would be interested to know what your "more crush" consists of, is it more of the bran being shredded and separated or are you really milling the endosperm down further. My understanding is the grain should be rolled through the mill so no fragment should be larger than the gap setting, if it is than the rollers are slipping or worn down so the grain isn't rolling through properly.

Sure, having your grain double milled from your LHBS could make a difference but if you own a mill setting the gap to your desired gap and running it thought once is ideal for many reasons. If youre a home brewer who is at the point of caring about your efficiency or consistency between brewers you should own a mill and not be depended upon whatever magical random setting or condition the communal mill is in.
 
If youre a home brewer who is at the point of caring about your efficiency or consistency between brewers you should own a mill and not be depended upon whatever magical random setting or condition the communal mill is in.

Absolutely!!
 
I mash in a bag and the last time I went to my LHBS, they double milled my grains after asking if I was happy with my efficiency (currently 65-70%, which I would prefer to be higher). I noticed no difference whatsoever, so either the grain crush is still not fine enough or that’s not the variable I need to change in my current system.

For those of you with your own mill, how fancy of a mill does one need to get in order to achieve a crush fine enough for BIAB/MIAB? I never had any interest in milling my own grains before now so admittedly I have done almost no research on what to buy.
 
I mash in a bag and the last time I went to my LHBS, they double milled my grains after asking if I was happy with my efficiency (currently 65-70%, which I would prefer to be higher). I noticed no difference whatsoever, so either the grain crush is still not fine enough or that’s not the variable I need to change in my current system.

For those of you with your own mill, how fancy of a mill does one need to get in order to achieve a crush fine enough for BIAB/MIAB? I never had any interest in milling my own grains before now so admittedly I have done almost no research on what to buy.

For the best results from your brewing efforts, a grain mill is a wise investment. You don't have to break the bank, but the main thing you'll accomplish is consistency compared to having others control your grind. Even if you don't hit crazy high efficiency numbers, many brewers will be pleased to have very consistent numbers albeit not unusually high. But, with some experimentation with your BIAB grind, your current numbers may likely increase.

Some mills are two roller and some are three roller systems. Three rollers are more expensive in many cases and the crush may be more consistent....but this is an arguable point. A decent 2 roller mill will run you around $100 and the 3 roller version a bit more.

You can crank it by hand, use a hand drill or get supremely innovative and run the mill with a direct drive motor. Top of the line mills (in my opinion) are Monster Mills while Cereal Killer is another less expensive option to look at. Hopefully some other HBT members will offer suggestions they have experience with.
 
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I BIAB and have my own cheap corona mill off amazon and have an efficiency problem. ;)

Every recipe I've followed for AG ended up with an OG .010 to 0.12 points higher than called for.
I double mill.
When I didn't and kept the crush about a credit cards thickness i got lower OG.
I use a drill motor to power the mill so milling 15lbs of grains twice takes like 15 mins from the point I cut the ziplock on the bag.

I also squeeze what I can out of the bag so maybe that contributes to the higher efficiency.

Is there a calculator to figure out how much base malt I can leave off the bill to make up for it or is it going to be trial and error?
 
I BIAB and have my own cheap corona mill off amazon and have an efficiency problem. ;)

Every recipe I've followed for AG ended up with an OG .010 to 0.12 points higher than called for.
I double mill.
When I didn't and kept the crush about a credit cards thickness i got lower OG.
I use a drill motor to power the mill so milling 15lbs of grains twice takes like 15 mins from the point I cut the ziplock on the bag.

I also squeeze what I can out of the bag so maybe that contributes to the higher efficiency.

Is there a calculator to figure out how much base malt I can leave off the bill to make up for it or is it going to be trial and error?


Once you have an efficiency number dialed in, you can put that number in Beer Smith. You can scale (reduce) your grain bill to show projected calculations so you don't exceed your target OG . I am familiar with Beer Smith altho I am sure other programs like Brewers Friend may do the same....just haven't used them.

BTW...that's a good problem to have to deal with...LOL
 
Once you have an efficiency number dialed in, you can put that number in Beer Smith. You can scale (reduce) your grain bill to show projected calculations so you don't exceed your target OG . I am familiar with Beer Smith altho I am sure other programs like Brewers Friend may do the same....just haven't used them.

BTW...that's a good problem to have to deal with...LOL

Normally i'd say it's not a bad problem but I brewed up some of EdWorts Pale Ale and it came in at %7.5.
I wanted an easy daily drinker not something that will make my eyes blur after beer two. :)
 
I BIAB and have my own cheap corona mill off amazon and have an efficiency problem. ;)

Every recipe I've followed for AG ended up with an OG .010 to 0.12 points higher than called for.
I double mill.
When I didn't and kept the crush about a credit cards thickness i got lower OG.
?

You should be able to adjust your corona mill to get a very nice fine crush with one pass thru the mill.

Setting a gap on the corona mill isn’t applicable imo as the burr grind plate is loosely mounted and can’t be gapped. Best to just tighten the mill until almost zero whole grains exit, or about the consistency of coarse corn meal. One pass thru a corona will overcrush if the mill is very tight ime, two passes shouldn’t be needed.

When people talk about two passes, it is typically on a roller mill with a wider gap.

If you like doing two runs, that’s fine just thought I’d mention it likely isn’t needed if the corona is adjusted properly.
 
You should be able to adjust your corona mill to get a very nice fine crush with one pass thru the mill.

Setting a gap on the corona mill isn’t applicable imo as the burr grind plate is loosely mounted and can’t be gapped. Best to just tighten the mill until almost zero whole grains exit, or about the consistency of coarse corn meal. One pass thru a corona will overcrush if the mill is very tight ime, two passes shouldn’t be needed.

When people talk about two passes, it is typically on a roller mill with a wider gap.

If you like doing two runs, that’s fine just thought I’d mention it likely isn’t needed if the corona is adjusted properly.

I'm new to this and its an amazon $30 job not an actual corona.
I worry about metal on metal and my drill motor gets hotter the tighter I make the crush so I double run it.
Like i said it takes little time but I'll make it tighter and see what that does for me.
May need the more powerful harbor freight drill.
Right now it gets like you describe with the double run.
 
Check...sounds like you are doing fine....run what you brung if the smaller drill works well with two passes than you’re good...

Yes again, almost all of the “Corona” mills spoken about here are the cheap Chinese copies, inexpensive but very effective if set up properly.

Yes again, at a tight setting the mill plates may clack and grind one another, I thought this may lead to some wear but after many sacks the grind plates on mine look as new, cast iron is some very hard material so wear doesn’t really happen at all ime.
 
... how fancy of a mill does one need to get in order to achieve a crush fine enough for BIAB/MIAB? I never had any interest in milling my own grains before now so admittedly I have done almost no research on what to buy.

Take a look at the Kegco 2 roller mill.

I have the Kegco 3 roller mill, and I drive it with a half inch electric drill. It works great. I see no reason the 2 roller mill would not do everything you need, be easy to adjust, and last a very long time.
 
I BIAB and grind using a Cereal Killer to 0.025" and regularly get 82% efficiency.
 
The Cereal Killer is on sale right now for $99, which includes shipping and a wood base -- that's a good deal.

I also have my mill set to .025", and get 82-83% efficiency.
 
x3 on the Cereal Killer. I've got mine adjusted as tight as it will go (can't remember the number) and hit high 70 to low 80s. Had the same problem mentioned above with Ed Wort's Pale Ale. Came in around 7.5% ABV.

To comment on Morrey's post, Brewers Friend also allows you to scale your recipe based on efficiency. I had no idea and when he mentioned that, I checked and its an option.
 
I just picked up the 2 roller Monster mill. I love knowing that I can depend on a consistant crush every time. Been very happy with the first two brews with the new mill.
 
I also experienced the joy of a tight grind. I also experienced overshooting my OG by quite a bit as a result.

I use a 2 Roller Monster Mill set to 0.022 on my mash in a bag setup. I had recently changed the gap tighter, was using a low speed drill instead of a high speed drill, and was doing a big grain bill for a 15 gallon batch so I assumed a 65% efficiency. I hit 82%.

Being able to grind fine with my mash in a bag setup raised my efficiency almost 10 percentage points, makes clean up easier, and gives me super clear wort. The only downside is I have to adjust all my grain bills down, due to the changes.
 
I’m still new to the process but all I’ve done is BIAB and I am starting to dial in my numbers now that I’ve got 4 batches under my belt in the last 5 weeks :D

I did an IPA yesterday based on a Brewer’s Friend recipe and, with my set up, it was stupid high conversion (92.5%) and my efficiency was upwards of 80% (probably could have been higher had I realized I made errors using the refractometer).

Regardless, I milled my own grain and went very fine but not “powdery” - the bag’s going to retain most of the bits anyway - this is a great way to brew and perfect for small batch guys like myself.

Cheers,
Dave
 
I always want higher efficiency, so 83% is very good, I would not worry. I want higher efficiency, in order to actually use smaller grain bills to get the ABV I'm after. I brew with the Grainfather, so cutting down on the recipe is always a good thing.

I don't care much about efficiency as long as it's consistent so that I can nail my numbers. That statement comes with one caveat....Brewing low to mid gravity beers (up to low 1.060's), you really want to get at least 70% if you want to brew super high gravity beers. The reason is that adding grain drops your efficiency given a set boil volume. With efficiency much under 70, you have to add so much more grain that it drops your efficiency, meaning more grain and even lower efficiency and, ultimately, you can't get there from here.

Other than that...70%, 80%...don't really care as long as it's consistent.
 
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