Corn Grind..when is it too fine?

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Corne
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Corn Grind..when is it too fine?

Post by Corne »

Hello,
My goal is to grind the dried corn from the local feed store into a product for an AG recipe.
The mash cooker is a BIAB pot with an immersion heater controlled. I don't know if I'll ferment on the grain or not, haven't got that far yet.
What will too fine look like? The grinder I've tried is slow and at the coarsest setting seems really fine. The grinder is a Mockmill Stand Mixer attachment.
Here is a picture of the grind next to a few kernels for reference.

Thanks.
Coarsest Grind I could get
Coarsest Grind I could get
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Re: Corn Grind..when is it too fine?

Post by ShineonCrazyDiamond »

Sounds like there ain't a lot of fat to be chewed here. Start with the coarsest abs go from there.
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Re: Corn Grind..when is it too fine?

Post by fizzix »

I do not have a mill and neither does the farmers' co-op where I get my cracked corn.
So what to do? For 2 years since I started doing this, the corn gets run through a kitchen blender
and turned into a fine flour. So I had the same question as yours: too fine?

Here's how I justify the answer "No. Not too fine."
Briess Whitepaper -specifically malt flour
ADI Forum

Interestingly, it looks like distilleries don't use flour because of the fire hazard it presents, and subsequent expensive safety equipment required for handling it!

I say relax, and go with it, chief.
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Re: Corn Grind..when is it too fine?

Post by Corne »

Fizz,
Thanks for the links and quick feedback.
Surface area is pretty much king for reactions between things. Power plants don't shovel lump coal into their boiler, it is pulverized and injected.
My concern isn't conversion or potential ABV, it's going to be whether or not the fines will pass through the screen basket of my cooker which could lead to'-
- collection at the heater element and possible scorching
- sucked into wash pump and clog the sparge spray tip or subsequently clog the plate type cooler.
I'm pretty sure I'll find out, as ShineOn suggested. What fun would the first cook be if everything was simple?
The slow little grinder did about 8# of whole corn, 1.3# of whole rye and 4# of malted barley in 4 hours. Corn was super slow (20 minutes a pound). The stand mixer got pretty hot!!
The local grain mill has cracked corn offering, I may do that when my first 40# bag of whole corn is used. Hate to waste the $6.50 FFS.
Alternately, the brew shop 30 minutes away will grind anything I bring in for a fee.
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Re: Corn Grind..when is it too fine?

Post by shadylane »

Corne wrote: My concern isn't conversion or potential ABV, it's going to be whether or not the fines will pass through the screen basket of my cooker
Just guessing, but I'd say neither the finely ground corn nor the liquid will pass through your cookers screen basket
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Re: Corn Grind..when is it too fine?

Post by CuWhistle »

Thing is, it's a PITA no matter what.
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Re: Corn Grind..when is it too fine?

Post by MtRainier »

Corn will clog it no matter what you do. 8)

I thought this was interesting about grinding into flour (barley, not corn). The distillery apparently doesn't like to use the barley flour and they send that to a local bakery since they run their mill output through a set of screens:

https://youtu.be/R-hz0ilhRlo?t=719" onclick="window.open(this.href);return false;" rel="nofollow
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Re: Corn Grind..when is it too fine?

Post by greggn »

It sounds like you're approaching this from a beer brewing perspective (e.g. , BIAB and sparging). I suggest you try a different, and arguably easier, approach ... read woodshed's post "Booner's Casual All Corn."

viewtopic.php?f=14&t=51458

I follow the same basic protocol for most all of my recipes. I grind to a flour, pour boiling (or near boiling) water over the grains, and add high-temp liquid enzymes as the temps drop downward. I ferment off-grain and strain using 600 micron bucket strainers.

https://www.usplastic.com/catalog/item. ... &catid=685" onclick="window.open(this.href);return false;" rel="nofollow

Honestly, the process is so simple that I mash and ferment in a room with wall-to-wall carpeting (granted, I throw a plastic tarp down beneath my pots and buckets but still, my wife doesn't even blink an eye).

I think it's a given that the blender/grinder you're using is not going to last long given the load you're putting on it. Get a cheap Corona/Victoria, drive it with an electric drill, and you'll knock out that grain bill in minutes rather than hours.
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Re: Corn Grind..when is it too fine?

Post by Twisted Brick »

Corne wrote: Surface area is pretty much king for reactions between things.
+1

Running cracked corn through my corona resulted in a quicker conversion and higher ABV, a process I would recommend to all who currently just run cracked corn. Hand-squeezing a grain-in ferment through a BIAB was easy, about 1hr for a 12gal mash with 24lbs of grain.

When I ran my corn through a hammer mill, the corn ended up finer than meal, just short of flour, and the job of hand-squeezing became tedious because the finer material escaped the mesh. Again, I experienced another small uptick in ABV, however the squeezed but uncleared wash produced a (NG) scorch (twice!) To answer your question, this is where I think a corn grind becomes too fine.

I have now taken to letting my hammer-milled bourbon washes clear in carboys and just siphon the clear off the top. One advantage is that the flour particles that made it through the BIAB settle and compact more tightly, ending up in a dense custard. The other advantage is that a finer grind allows for more grain in the mash.

Because the hammer mill has created additional layers of work, I'm currently working on a steam masher/stripper. So if you don't want to end up going down this road, I'd recommend not grinding past a coarse meal.
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Re: Corn Grind..when is it too fine?

Post by CuWhistle »

I asked elsewhere but no answer yet and it is directly related to this topic. What do you do with the dense custard? Is it just waste? My custard sediment from a recent AG amounts to more than 25% of the total recovered volume of liquid after squeezing and 3 days of settling. It immediately blocks any attempt at filtration.
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Re: Corn Grind..when is it too fine?

Post by Twisted Brick »

25% after squeezing is a lot. I experienced this early on and eventually discovered grinding it a little finer caused it to compact more densely. I'd say the hammer-milled/squeezed wash amounted to ~15% of the carboy volume, something I could live with. You also might try using a tighter-mesh squeezing implement.

What do I do with the custard? It ends up in the compost pile. It's so thick it sun-dries into a cake and has to be broken up into the soil.

Recently, I have considered saving a quart of it and boiling it with some yeast to add to my next ferment as nutrients, but haven't gotten around to it, wondering if AG ferments actually benefit from added nutrients.

Hope this helps.
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Re: Corn Grind..when is it too fine?

Post by jonnys_spirit »

I just purchased an agristore grinder and it’s well worth it turn 35lbs of feed corn into corn flour and do larger ferments in a 32g brute. Still working out my #’s but i grind it fine, ferment on-grain, and squeeze. I’ll be adding a thumper soon to cook the slop too so eff that squeezin once I can move on.

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Re: Corn Grind..when is it too fine?

Post by CuWhistle »

Thanks TB. I'll see if I can improve my squeezing to reduce the custard volume. I pitched yeast into 19 litres of liquid plus grain and ended up with nearly 4.5 litres of custard and only 12.5 litres of cleared mash. I've got some landscapers biomat random direction fabric but it just holds it. Virtually no liquid comes through.

Edit: I must have been a bit lazy. I was able to go back and get another 2 litres or so out of the custard which brings it more into line with your numbers. I have to work out a better system though. Interesting that clear was wicking up and over the top of the bucket with the biomat catcher / strainer. Path of least resistance was up.
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Re: Corn Grind..when is it too fine?

Post by Corne »

Well, I gave it my first shot!
This is my first mash, ever.

Jumping to the end, almost all of the visible pieces of grain stayed in the 300 micron screen basket. The only pieces that did not were due to flowing over the edge of the basket, more on that in a sec.

My grains and water additions were : 8 gallons water, 8 lbs of corn, 1.3 lbs of rye and 4 lbs of 2-row malted barley (briess).

The corn cook was not what I expected.
I heated to 150 deg F and added the corn and held temp for 15 minutes.
I raised temp to 162 deg F and added 1/2 tsp of alpha amylase.
I raised temp to 205 deg F (took 45 minutes to get there) - this is where the spill over happened. I was recirculating water with a pump from below screen basket to back on top of the screen basket. Water in = Water out, or so I thought. When I wasn't stirring, there was a barrier at the bottom grains that didn't let the water fall through the basket. So I was filling the basket until overflow, which caused some floaties to spill over. I understand this but what happened later I am not clear on.
The corn cook went on for 90 minutes. The mash never thickened like a porridge, but the liquid was really thick and "slippery". There was no sweetness to the mash.
I lowered temps with a plate cooler down to 149-ish. Temps dropped really fast when I added the small amount of rye. Down to 140 deg F. I raised temp to 147 deg F and held 30 minutes.
I then added the malted barley and 1/2 tsp of alpha amylase. 20 minutes later the mix was really sweet.
30 minutes later the iodine test resulted in a clear result. Started a cool down and added glucoamylase as I was passing through 142 deg F. Cool down took a long time, longer than I expected when compared to the drop from 205 to 149-ish.

OK, when I pulled the heavy ass grain basket up, I noticed my pump was not moving the wash. There were only a couple teaspoons of grain in the wash. What was clogging my pump screen was what i believe to be the "custard" described earlier. It was an opaque layer completely covering an inch or two of the bottom of my pot. Any stirring I did earlier was all inside the basket, 4" high or higher in the pot. I stirred that up with my paint stirrer-ma-bob. I performed another iodine conversion test, and the result was black. Crap! It was way too late at night now to fix it, which I wasn't sure what to do anyway. I just hope the enzymes will continue to work during the ferment.
Once I hit 75 deg F, I did an initial specific gravity, which came out at 1.050. And it was still sweet.

So, was that custard the starches that came out of solution because I couldn't stir below the basket? That custard really burns well on the heating element, I'm still trying to get it off.

Once I stirred it up, what would the best course of action be? Heat back up and wait for more conversion?
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Re: Corn Grind..when is it too fine?

Post by nateboussad »

To get very specific - each grain should be divided into exactly three pieces. So, real AG brewers crack grains one at a time to ensure proper grind.
Last edited by nateboussad on Fri Sep 06, 2019 4:14 am, edited 2 times in total.
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Re: Corn Grind..when is it too fine?

Post by Corne »

Ha! Would that be three equal pieces?
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Re: Corn Grind..when is it too fine?

Post by CuWhistle »

Well that just goes to show how difficult / tricky full conversion of corn / AG really is. The "custard" I got literally held liquid like a bucket. Once the biomat I tried to use for straining was coated in the stuff it didn't leak. I fermented on the grain and my corn was ground to meal, so my custard would have been corn and yeast mixture.

I use the same biomat as the top layer of my fish pond bio filter and it will allow the pond water to filter through for months.

I smashed my kernels into about 3000 pieces / kernel. I'd imagine trying to gelatinize 3 pieces / kernel would take a fair bit of high temperature cooking.
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Re: Corn Grind..when is it too fine?

Post by Setsumi »

I use fine corn meal. where I live it is a staple food and you can buy it in any food store. commercial brands are degermenated and fine, not flouer but fine.

I follow booners casual all corn method to cook it with enzymes and filter it post fermentation with geotechstyle fabric as described by ga flatwoods. the filtration is to me pretty hands off but I do it over a 24h period. The meal will retain 1lt per kg, I am certain you coud sqease more out but I don't at this time.
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Re: Corn Grind..when is it too fine?

Post by nateboussad »

Game corn is just dried, not gelatinized, so you'll have to cook it before you can mash with it. The same problem exists with rice, which is why you use instant rice instead of dried.
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Re: Corn Grind..when is it too fine?

Post by cayars »

I'll give you another option and something to try.

Do two batches back to back so they ferment at the same time. Use exactly the same grain bill for both batches.
On the first batch ferment on the grain then sparge after fermenting.
On the second batch lauter it like a brewer would and ferment off the grain.

Note the SG you get for both and what your ABV is after fermenting.
Now run them both and tell me which taste best and which was the easiest process to use.

I find a very distinct difference in taste between the two with the lautered batch tasting much better. I think this has to do with NOT fermenting with the grain hulls and all the proteins in them.

It's far easier IMHO to lauter then it is to sparge after the fact as you don't have the yeast to mess with which you will have mixed in with your grains if you don't lauter and ferment on the grain.

Now if you lauter you can use more grain per gallon of water as well IMHO. You can immediately do a sugar head on top of the lautered grains as well if you want to pull any remaining wort from the grains. Just add warm water (no sugar) and lauter the grains for enough liquid needed for the sugar wash. You'll lauter this into another vessel or carboy so you end up with only fluid. You can use your hydrometer or refractometer to check to see how much sugar water is being lautered to know when to stop and not waste your time and know when the grains are spent of useful "converted sugars". This allows you to make a great clean whiskey and use the sugar head as poor mans whiskey or use it for a neutral with a bit of character unlike a plain sugar wash.

The one nice thing about going the lautering method is that once it's done fermenting you can rack off the liquid right down to the yeast bed as there won't be any grains to deal with and you have nothing but clear liquid to put in your still.

You don't need to worry about trying to squeeze every last bit of water from the grains with the first lauter because anything left will benefit the sugar wash. After you lauter the sugar wash (which again is clear of grains) you can perform one more lauter with warm water of the grains. This time you save this lautered fluid back for the next batch of grains you make (or sugar wash) as it will have yet a bit more ABV potential. But by this time the grains have been lautered 3 different times and are spent and can be discarded.

Knowing how much to lauter into your first batch (whiskey) is just a matter of how much grains you started with and your hydrometer or refractometer reading. You control the amount of lauter used for the first and second batch and where you cut this off, knowing you will lauter it again for the second batch or even a third time to have a base wash ready and usable for round two.

I hold for 90 minutes at 190+ F for corn, add other non-malted grains at 170 F or lower and hold for 60 minutes (can cool on it's own) and then another 90 minutes at 148 F and dropping. After 90 minutes you can force cool the wort if you like. This gives good enzyme conversion for me. There will still be some trace enzymes present which will benefit the follow up sugar wash a bit as well. I use a drill and mixer during this process and mix every 10 to 15 minutes after adding enzymes and about every 30 minutes or so otherwise.

Even if you work in small batches of 8 to 10 gallons (igloo cooler or similar) you can do an 8 gallon (whiskey batch) followed by a 4 to 8 gallon sugar wash. Nothing says the two batches need to be the same size. The sugar wash is just another step to lauter the grains and get the most out of them with hardly any work on your part. The sugar wash doesn't require any specific temps, just warm enough to melt the sugar so this is fast.

You can pretty easily do 2 sets of batches a day this way with a single igloo drink cooler. I use two igloos coolers and do them back to back as fast as I can heat water using a couple of BOPs. Doesn't take long to fill two Brute trashcans (one pure grain wash and one sugar wash) this way.

So essentially two batches off the same grains both ready to ferment the same day and then cleanup. I'm not positive but I believe, not having the grains in the ferment seems to help with "sour flies" as well. I notice less fly problems in the summer when the grains aren't kept around.

But I'd definitely recommend trying an on the grain ferment vs off the grain ferment just to compare taste of finished product if you have the ability to lauter (not hard to rig this up). There are plenty of Youtube videos that show how to do this. Even if you don't have the "proper" method to lauter try a grain bag once to seperate the grains from the wash to ferment off the grain for the comparison run. You probably due this anyway right now after you are done fermenting and it will be less messy as you don't have the yeast to contend with and can take a hydrometer reading at any time to see the SG of the liquid still coming off the grains.
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Re: Corn Grind..when is it too fine?

Post by Corne »

The posts here have been great!
I've been grinding the corn like the original post. Having the corn this fine has really helped keep the mash simple. What I am doing with the corn and cereal grains is pretty much what Cayars describes in his post.

To not spend so much time cleaning up, I have been running mashes back to back. Each mash to a 6 gallon fermenter. Each ferment stripped. Then the results of both stripping runs combined for a second spirit run.

I ran a little experiment this past weekend. After I pulled off the first wash from the cooker there was still about a a quart of wash in the pot and the pile of mostly squeezed grains left in the cooker basket. I added 6 gallons of water directly to this for my second batch. There was so much sugar still in the "leftovers" that the specific gravity of the second batch at this point was 1.024. That's .024 points that would have been wasted if I wasn't doing a back to back mash. Once the old grains were fully rinsed, I dumped them and began with the new grains. The second batch finished .012 points higher than the first batch, 1.082 vs 1.070.
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Re: Corn Grind..when is it too fine?

Post by Beerswimmer »

The stores around here have 25lb bags of masa for dirt cheap, has anyone used masa? It's nixtamalized corn ground to flour.
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Re: Corn Grind..when is it too fine?

Post by Stonecutter »

greggn wrote: Sun Jul 28, 2019 7:51 am It sounds like you're approaching this from a beer brewing perspective (e.g. , BIAB and sparging). I suggest you try a different, and arguably easier, approach ... read woodshed's post "Booner's Casual All Corn."

viewtopic.php?f=14&t=51458

I follow the same basic protocol for most all of my recipes. I grind to a flour, pour boiling (or near boiling) water over the grains, and add high-temp liquid enzymes as the temps drop downward. I ferment off-grain and strain using 600 micron bucket strainers.

https://www.usplastic.com/catalog/item. ... &catid=685" onclick="window.open(this.href);return false;" rel="nofollow

Honestly, the process is so simple that I mash and ferment in a room with wall-to-wall carpeting (granted, I throw a plastic tarp down beneath my pots and buckets but still, my wife doesn't even blink an eye).

I think it's a given that the blender/grinder you're using is not going to last long given the load you're putting on it. Get a cheap Corona/Victoria, drive it with an electric drill, and you'll knock out that grain bill in minutes rather than hours.
There’s a video of a guy using a micro filter with some kind of vibrating tool on a Corn mash. If anyone knows where to get that link I’d be extremely grateful. In the meantime I’ll keep looking through the booner thread.
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Re: Corn Grind..when is it too fine?

Post by Twisted Brick »

Stonecutter wrote: Tue Sep 06, 2022 4:48 pm
There’s a video of a guy using a micro filter with some kind of vibrating tool on a Corn mash. If anyone knows where to get that link I’d be extremely grateful. In the meantime I’ll keep looking through the booner thread.
Hey Stoney, you lookin' for dis?

viewtopic.php?p=7422313
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Re: Corn Grind..when is it too fine?

Post by Stonecutter »

YES! MichiganCornhusker that shit is brilliant!
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