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Looking for suggestions on separating grain after mashing

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I have been making a single malt in a mash tank.  I ferment on grain and found the grain all flowed to the top during fermentation which pretty much separated it out.  Now that I do a finer mill (to get better conversion, went from 13.3 to 16.8), the grain has become hard to separate out easily before I distill.  Any low cost suggestions?  I ferment in a Letina 2000 liter White Wine Fermenters with Cooling Jackets—Closed TopConical Bottom tank and thought about putting in a false bottom to allow the grain to collect on the top which can be scooped out for the pigs.  People think this would work?  Other suggestions?

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Easiest option is to stay coarse and sacrifice the slight gain in yield for an easier workflow.  If it worked before, stick with it.  We separate the grain post-distillation, and found essentially the same - milling the corn any finer than the crack we receive it makes separating a multi-hour process, and we are left with wet sludge and not fluffy dry grain.

How are you separating the grain today in the Letina?  Is it just staying behind in the fermenter when you drain?  We find that fermentation isn't complete until after the cap drops, so not following how you are taking it off the top.

Consider maybe an intermediary separation tank.  We have tanks on wheels with screens that we use to separate post-distillation.  It's not very high tech at all, but it is working well for us, and we get reasonably dry spent grain.  The tanks aren't large enough to hold the full contents, so we make multiple passes - but we're finding it's faster to separate multiple small batches than a single large batch (as the screen gets occluded, etc).

 

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Most of the rest of the world makes "single malt" by separating the grain before fermentation, almost exactly as beer brewers do.

Use a lauter screen, don't add all your water at start , rinse remaining sugars (sparge) with rest of water. As mentioned above you could do several small batches.

When/if you separate grain after fermentation I assume you don't rinse the alcohol out of the grain? You are throwing out some of your alcohol, but have happy pigs.

A lauter screen works by the grain forming a fine filter bed on top of the screen. A screen could have slots of say 0.2 mm but if the grain bed settles properly it could filter particles down to 0.002 mm. During active fermentation most of the fines would drop through the screen. To trap those fines you would need to recirculate to the top of the grain bed. I very much doubt you could set up the grain bed as a good filter as I suspect the barley chunks would now be too soft and the bed would collapse and block.

I would be very interested to hear if anyone has set up a decent filter bed post fermentation.

 

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Lauter first and ferment off the grain. With proper sparging you should be able to achieve good yield

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23 hours ago, PeteB said:

Most of the rest of the world makes "single malt" by separating the grain before fermentation, almost exactly as beer brewers do.

Use a lauter screen, don't add all your water at start , rinse remaining sugars (sparge) with rest of water. As mentioned above you could do several small batches.

When/if you separate grain after fermentation I assume you don't rinse the alcohol out of the grain? You are throwing out some of your alcohol, but have happy pigs.

A lauter screen works by the grain forming a fine filter bed on top of the screen. A screen could have slots of say 0.2 mm but if the grain bed settles properly it could filter particles down to 0.002 mm. During active fermentation most of the fines would drop through the screen. To trap those fines you would need to recirculate to the top of the grain bed. I very much doubt you could set up the grain bed as a good filter as I suspect the barley chunks would now be too soft and the bed would collapse and block.

I would be very interested to hear if anyone has set up a decent filter bed post fermentation.

 

PeteB, I have set up nice grain filter beds post fermentation. I have not done this on commercial size equipment yet, but it works on my home brew set up. I did, however, design the equipment with the intentions of scaling up for my micro distillery. Of course if you are doing mash bills of high wheat, rye or corn then this can get difficult without adding rice hulls.

http://www.iskiebaedistillery.com/2015/12/28/iskie-bae-distillery-grain-filtersparge-arm-concept/

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I know that a lot of us like to keep the tradition of simplicity in order to make a more consistent or "genuine" product, but there are a few issues that I find with on grain fermenting and distillation. For one I find that it complicates the process of fermentation by restricting the portability of the mash from vessel to still as well as takes up precious space in your fermentation vessel. Not only that, I believe you end up throwing away some of your potential yield within the grain if you separate it before distillation. I also feel that it has the potential to create more off flavors, but that's simply my opinion. The final reason I opt to separate early on is because I don't like the idea of grain in the still possibly burning and again taking up precious space in the pot. I do like the beer brewers method for a number of reasons, first of which is that it's what I have actual commercial experience with. Secondly, I have found that even though it adds a little bit of a chore in the beginning it pays off with consistency and yield in the long run. It also falls more in line with the entire process "organically"; you're repeatedly transforming and separating a solution. Good luck to all. 

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Just a quick update on my side.  I purchased a custom lauter screen that will sit in the bottom of my tank.  It will let me lauter before fermenting or after fermenting but before distilling.  I will let folks know how it works out and post some pictures.

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I believe the spacing is 0.03 inches.  Fairly fine but that is the typical size they make.  It is made in three sections so it can fit through the opening in the tank and just sits on the bottom of the tank.  I should have it this month.  I want to try it out on my single malt before moving to my bourbon.

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The best way to mash barley is to sparge using a false bottom with 3/32" holes on 5/32" centers.  Separate out the sweet Barley water and ferment off the grain.

Corn is a completely different critter.  The best way to mash corn is to cook then ferment on the grain and distill on the grain.  The same is true of rye.  All that it takes is a jacketed still and mash cooker or a combination jacketed still and mash cooker.  I can put you into a 105 gallon mash tun still for around $14,000.00 this includes a 6" 4 plate copper column, agitator and baine marie heating system.  If you are screening your corn mash you may be throwing away more ethanol than you think.  One of our customers had been throwing away over 20% ethanol with his grain.  Also, grain in distillations of corn mash produce a superior barrel aged Bourbon and Whiskey with more flavor and body.  We have reasonably priced mash pumps that can pump the thickest corn and rye mashes.  Our pumps will even pump peanut butter.  Give me a call 417-778-6100 or shoot out an email to paul@distillery-equipment.com http://distillery-equipment.com      http://moonshine-still.co

 

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I got the screen today.  I attached photos of it in the crate and in the tank.  It is pretty heavy but manageable.  Fits in the tank pretty well, not too tight.

IMG_2415.JPG

IMG_2416.JPG

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That will be a plug fest with corn, or high corn mash bills. Sorry to tell you that.

Barley, it will work just fine as long as you "crush it" not mill it into a flour.

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First run today with the single malt, here is how it came out.  Grain was pretty dry and easy to shovel out.  Basically I distilled on grain and the pumped into this tank and then pumped off the liquid.  There was a little learning on how to fulling drain off the liquid but it worked out pretty well.

 

 

IMG_2419.JPG

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I know that a lot of USA distillers distill "on the grain". As many of you would know, Single malt distillers in Scotland only distill a clear wort. They do not want any grain husk in an water above a maximum of 80 deg C which is the hottest they will sparge their grain bed. Hotter than 80c extracts too many tannins.

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That a Letina tank geek?  Debated something similar but shovelling it out sounded like a pain in a 4000L tank.

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Just a warning.

If the corn does plug up your screen, and you have a good powerful pump hooked to the bottom of the tank. You could run the risk of creating such a vacuum that you could collapse the screen, buckle or implode the bottom of the tank, or collapse the hose. Those tanks are not very thick.

Just keep an eye on it.

Be safe.

Just trying to help.

 

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1 hour ago, GeekSpirits said:

Yes, it is a Latina 2000liter tank.  We use a small plastic snow shovel.

It looks like one of the shovels for pulling ice and snow off the roof would work good.

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29 minutes ago, Dehner Distillery said:

 

29 minutes ago, Dehner Distillery said:

Just a warning.

If the corn does plug up your screen, and you have a good powerful pump hooked to the bottom of the tank. You could run the risk of creating such a vacuum that you could collapse the screen, buckle or implode the bottom of the tank, or collapse the hose. Those tanks are not very thick.

Just keep an eye on it.

Be safe.

Just trying to help.

 

I will definitely do a small amount the first round so I have less mess to clean up if it doesn't got well.  I found with the malted barley, I have to reverse the pump and then reverse it back a few time to complete pull off all the liquid.  I am not worried about the screen collapsing because of the construction.  Hendrick Manufacturing did a really nice job on the construction.  I do think a larger pump and shorter hoses could help.  You are 100% correct on the retina tanks being thin so definitely need to keep and eye on it.

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I can tell you from experience that corn (or any grain ground flour-like) is a poor candidate for lautering using a standard wedgewire false bottom.  Even improperly processed rye (read: lack of beta glucanase)  will cause issues.  All of my research points to the need for a centrifugal sifter such as Kason makes.  They seem to have the best price point although even remanufactured they are north of $10,000.  I look forward to be proven wrong!

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