what do you think is a reasonable upper grain bill for a 10 gal mash tun?

Brewing Processes
1

I have a new 10 gallon SS Brewtech insulated mash tun (thanks to my wife for christmas) ,  and since i have some neighbors and in-laws that like my beer I am thinking about expanding my batch size up from my current 5 gallon.  Any ideas on what a reasonable upper limit would be for my mash tun?  I thought perhaps I could try an 8 gallon recipe and see how it goes.  The nice thing about the new mash tun is the design is a zero dead space so maybe that helps by a pint or two… :).  I typically fly sparge,  sometimes batch,  but I feel like I get better results on a slow fly sparge so thats what i plan for.

And also I will of course need to split the batch to two fermentors so I assume having a little extra headspace (4 gallons instead of 5) in the fermentor is not a problem assuming the co2 will push the air out anyway.

Thank you!

Tom

2

As an upper limit for water to grain ratio you could use 3 qts/lb and at that value you could mash-in 12 lbs. of grain into a 10 gallon mash tun.

As a lower limit for water to grain ratio you could use 1.25 qts/lb and at that value you could mash-in 25 lbs of grain into a 10 gallon mash tun.

Anywhere in between those 2 limits seems workable.

3

You should be able to mash 24 lbs. of grain with a water to grain ratio if 1.25:1 with a little space left over.

The “Can I Mash It” Calculator here is a great tool:  Green Bay Rackers--Mash Calculators

4

Thanks for the input ( and the calc link !).  Will I also increase the chances of a “Stuck sparge” with the higher grain bill?  I have never experienced one wth my 5 gallon batches and I am not sure how difficult it is to fix.

5

The thicker your mash, the slower it will drain, but not necessarily make it any more likely to get stuck. At least in the ranges provided by BigMonk

6

In my experience, using batch sparging, using more grain will not increase the chance of a stuck runoff.

7

Thanks guys!  I will play around with recipe scaling in Brewsmith and see what kind of grain bills I get for different volumes and beer types.  It is quite a hobby… one year ago I brewed my first batch from an extract starter kit… and now I find myself thinking about a 20 gallon kettle for larger batches.  I would need at least a 15 gal to do an 8 gallon batch I think, so it prob makes sense to spend a little more and get the 20 gal.

getting a fresh 16-18" of snow here today so I won’t be brewing for a little while.

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Great resource for quick checks.

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Tom, just another note, since you are using Beersmith, there is a section on the mash page that tells you your mash volume and will highlight it in red if the mash tun listed in your equipment is not big enough to handle the given mash parameters. The other calculator is also accurate, but if you are already in beersmith, it will save you a step

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Thank you Frank!  I was just messing around with Brewsmith and scaling a chinook IPA to 8.5 gallons.  I will check out the mash tool as well.  so many options…

*** using the brewsmith tool it looks like I may not have the mash tun space for an 8.5 gallon batch using a fly sparge (slightly over the 10 gal mark…) but batch sparge would work.  I think I need to learn some more before going to the larger batch.

11

^^^This

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If it’s a true 10 gallon capacity, then yeah, 25 lbs will be the max at a ratio of 1.25 qts/lb. The mash will go right up to the rim, so stir carefully. Happy mashing!

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I mash in kettle and transfer to 10 gal. lauter tun, zero-dead space.  I use 1.25-1.3qt/lb and 10lb gives just over 5gal in in lauter tun.  So youd think the 10gal limit would be <20lb. But it might not scale in a linear fashion,  absorption is tricky.  Hopefully the calculators have good input on this.

14

I think the question was more about capacity rather than extract yield. I agree that for a more detailed assessment of the gravity produced you’d have to account for absorption, but for a capacity calculation you just want to know the strike volume and grain displacement volume.

15

If I was at home I could tell you exactly - I got a 13g batch at 1.082 og after boil with around 30lbs (I think 32) of grain in my 10g home depot drink cooler. it was batch sparged and I don’t believe I got quite to 1.25 q/lb ratio due to literally being at the brim. I did suffer a bit on efficiency as that same grain bill should have netted me closer to 14-14.5g at the same gravity per my usual efficiency.

With fly sparge I would say your upper limits are somewhere around 25lbs of grain which is more than enough for 10g of almost anything!

I suppose I should note, my cooler capacity is slightly larger than 10g however (probably around 10.5-11 technically)

Best of luck to you!

16

Bear in mind that a 10-gallon mash tun often holds a little less than 10 gallons.  Only experience can tell you what the tru maximum is.

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Yeah, those jerk cooler manufactures calculate capacity including the space inside the lid. I assume my 70qt is 62qt.