Can't fit grain bill for high efficiency - work arounds?

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Corey22

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Hi all,

Brewing a double IPA this weekend which has. 21lb grain bill. I just had issues with a 17lb grain bill a few months ago, and this will only exacerbate it. It is a 5gal recipe, and my mash tun works well with most recipes that don't have such a huge grain bill.

The issue is I can only fit probably half or maybe 3/4 of the water in the mash, then I sparge the normal amount and stuff I didn't use. On my last one my efficiency was pretty poor .

I tried googling some things and couldn't find a keyword to use as I'm sure there's something that exists, maybe doing a double mash? Fill, steep for an hour, empty, fill, steep, then do a slow sparge? Maybe?

Any help is appreciated. Thanks!

On a side note, I'll be stepping up to 10gal batches probably by end of year, and would he doing huge grain bills, probably 40lbs+ I know I've seen igloo cooler styled mash tuns but am curious if there are any better solutions that came out since I read those posts.
 
What size is your MT? Are you doing BIAB, three vessel/kettle, etc.?? I've had zero issues mashing over 20# in my 15 gallon Spike+ MT before. I have a batch on deck that currently calls for 30# which will fit as well. I don't do the 'no-sparge' method. If your current MT won't fit the grain for batch sizes you're brewing, it's time to either adjust your method to keep using it, or get a larger MT.

I've had a cooler MT in the past. I got rid of that and went kettle MT years back (keggle first, then the Spike+ more recently). Don't miss the cooler MT one bit.
 
Reiterated mash. It takes longer, but it is also much simpler and easier.

Essentially do one mash with some of the grains, then use that wort as your base for a second mash. I've done it in similar situations to your description above, and the beer turned out great.

https://grainfather.com/reiterated-mashing/

Good source! I think I understand it but I'll read through it a couple times.

What size is your MT? Are you doing BIAB, three vessel/kettle, etc.?? I've had zero issues mashing over 20# in my 15 gallon Spike+ MT before. I have a batch on deck that currently calls for 30# which will fit as well. I don't do the 'no-sparge' method. If your current MT won't fit the grain for batch sizes you're brewing, it's time to either adjust your method to keep using it, or get a larger MT.

I've had a cooler MT in the past. I got rid of that and went kettle MT years back (keggle first, then the Spike+ more recently). Don't miss the cooler MT one bit.

I have a 8gal mash tun with a false bottom that I fly sparge into a final 10gal boiling kettle. I've eyed the kettle mash tuns, no issue with heat retention?
 
Since my system is electric, plus I do the constant recirculation of the mash, I have no issues with maintaining mash temperature. Control panel makes it easy. I also have the system in the garage (steam condenser lid on the BK makes that an option). HLT has the 50' stainless HERMS coil in it (15 gallon HLT). I've thought about upgrading the MT and HLT to 20 gallon vessels, to match the BK, but with what I'm brewing I've not needed to do that. I've been putting 9-10 gallons into the conical with the batches lately. The coming recipe is an imperial stout, so I might go a little lower on end of boil/into fermenter, levels. But not all that much (target is 8 gallons into conical). I fill either a 2.5 or 3 gallon keg, then can the rest of each batch. Gives me enough to have (on tap), allow people to have some when visiting, and then give them cans to go home with.
 
Reiterated mash. It takes longer, but it is also much simpler and easier.

Essentially do one mash with some of the grains, then use that wort as your base for a second mash. I've done it in similar situations to your description above, and the beer turned out great.

https://grainfather.com/reiterated-mashing/
A reiterated mash is the solution if your mash vessel is too small to mash the entire gain bill, but it will have the same large grain bill efficiency hit as a single mash. There's no free lunch to be had.

Brew on :mug:
 
It sounds like you might be close?

As long as it doesn't thicken your mash toomuch, a second batch sparge? Reduces your strike volume, adds a few more points of efficiency.

Keep each running to as close to 1/3 preboil volume as possible. Be sure to fully drain each sparge before the next.
 
It sounds like you might be close?

As long as it doesn't thicken your mash toomuch, a second batch sparge? Reduces your strike volume, adds a few more points of efficiency.

Keep each running to as close to 1/3 preboil volume as possible. Be sure to fully drain each sparge before the next.
At 1.25 qt/lb mash thickness, 21 lb of grain will create a mash volume of ~8.25 gal. At 1 qt/lb the volume would be ~6.95 gal, which would still be tough to dough in using an 8 gal MLT.

Brew on :mug:
 
Why force it? just figure out how much base malt you need to be able to convert any low- or no-diastatic grains, and replace the rest of the base malt with DME at flameout.

Or if you wanna use as much grain as possible, just put in as much as you can realistically fit in your mash Tun with your specialties and swap the remainder for DME.
 
If you use a reiterated mash process which I do all the time when I make my Imperial Stout recipe you're probably going to need more than a 10 gallon kettle to do a 5 gallon batch. While I use work to mash the second iteration I always use water to sparge and I end up with 7.5 gallons or more pre-boil volume.
 
It sounds like you might be close?

As long as it doesn't thicken your mash toomuch, a second batch sparge? Reduces your strike volume, adds a few more points of efficiency.

Keep each running to as close to 1/3 preboil volume as possible. Be sure to fully drain each sparge before the next.
Doesn't reducing strike volume pull out less and reduce efficiency?

If you use a reiterated mash process which I do all the time when I make my Imperial Stout recipe you're probably going to need more than a 10 gallon kettle to do a 5 gallon batch. While I use work to mash the second iteration I always use water to sparge and I end up with 7.5 gallons or more pre-boil volume.
Heh, the last batch I did had 8 gal in the 10gal pot, that was fun babying to not overflow. Used the anti foam stuff and it worked out in the end.

Using that much DME with the grains will require a recalculation of your water mineral additions. DME already has minerals.
I do water chemistry for my espresso. But haven't done it for beer yet, just using spring water for now.
 
Doesn't reducing strike volume pull out less and reduce efficiency?

Moving some water out of the mash to a (or second or third) sparge increases the overall lauter efficiency. Best efficiency is found when each running is roughly equal to each other and each is fully drained before the next sparge. A single batch or dunk sparge will achieve an extra ~8% lauter efficiency over no sparge. A second batch sparge will gain a couple more points. A third will approach the efficiency of a well performed fly sparge. Doug's got a chart illustrating this.

Heh, the last batch I did had 8 gal in the 10gal pot, that was fun babying to not overflow. Used the anti foam stuff and it worked out in the end.

My typical batch is 4.3G in a 5G kettle. Definitely requires a close eye and judicious use of the throttle. A very gentle 'Level 1' boil is all you need. First wort hops are excellent anti-foam stuff.
 
Doesn't reducing strike volume pull out less and reduce efficiency?
...
Increasing the ratio of grain to pre-boil volume reduces the lauter efficiency (and thus mash efficiency), all else being equal. So, less strike volume in a no-sparge process will give lower eff, but changing to a batch sparge process and moving water from strike to sparge, with same total volume will improve efficiency.
Moving some water out of the mash to a (or second or third) sparge increases the overall lauter efficiency. Best efficiency is found when each running is roughly equal to each other and each is fully drained before the next sparge. A single batch or dunk sparge will achieve an extra ~8% lauter efficiency over no sparge. A second batch sparge will gain a couple more points. A third will approach the efficiency of a well performed fly sparge. Doug's got a chart illustrating this.
...
Why yes, I do have a chart. And, nice summary of the salient points.

Efficiency vs Grain to Pre-Boil Ratio for Various Sparge Counts.png


Brew on :mug:
 
Increasing the ratio of grain to pre-boil volume reduces the lauter efficiency (and thus mash efficiency), all else being equal. So, less strike volume in a no-sparge process will give lower eff, but changing to a batch sparge process and moving water from strike to sparge, with same total volume will improve efficiency.

Why yes, I do have a chart. And, nice summary of the salient points.

View attachment 763135

Brew on :mug:
Interesting! So per this, I should do as much mash water as possible, but then do 3 full batch sparges?
 
Why not just mash 2 half batches back to back? Yes, it will take a good extra hour to do the 2nd mash. But the outcome is very predictable, while volumes vs. vessel space are much more manageable.

To increase efficiency, store the first runnings of each mash in a holding vessel (e.g., large bucket). Sparge the grist of each mash once with the proper amount of water. IOW, just collect 2nd runnings, omit 2nd sparge (3rd runnings). Reason is, you don't want to overdo the sparge, because any excess volume would need to be boiled off, which takes time and costs energy, for very little gain in additional fermentables.

Then combine the 2nd runnings and boil that down to the correct volume before adding the 1st runnings to the boil kettle. Finally, boil the wort as you'd normally would, hop additions, chilling, whirlpooling, etc. as usual.

Plenty of variations on this theme to fit your system and processes.
 
If it were me, I'd scale back recipe to fit the equipment that you have. Above suggestions will work too, but of course add time & effort. For me time efficiency is more important than grain bill efficiency.

Sounds good that you will be up sizing your rig. For what it is worth, my mash tun is made out of 15 gallon sanke half keg, & I make 10 gallon batches. I can't go over 23# grain bill without starting to loose efficiency, you'll need a pretty big vessel to handle 40#s, and still will not have great extraction with water volume needed for 10 gallon batches.
 
Another idea is to just use a second cooler and have the other half of the mash in it.
Run process on the first, dump the spent grain, then dump the second cooler into the mash tun and run process on it, utilizing the false bottom or manifold or whatever that you have in your mash tun. You could even use on of the styrofoam coolers and line it with a trash bag and dump that into your mash tun.
 
On a side note, I'll be stepping up to 10gal batches probably by end of year, and would he doing huge grain bills, probably 40lbs+ I know I've seen igloo cooler styled mash tuns but am curious if there are any better solutions that came out since I read those posts.
Sorry I didn't see that note. ;)
Large rectangular coolers with good wall and lid (!) insulation would be the roomiest, easiest to stir solution. They're good for batch sparging, not so for fly sparging, due to the larger surface while being relatively shallow.

I have two 13 gallon rectangular cooler mash tuns and batch sparge. One is basically a spare for larger, high gravity batches, mashing in both concurrently. I like the CPVC manifolds, but a braid will probably work just as well in that size.
One of my brew friends has a converted 25-30 gallon cooler mash tun, but only brews 10 gallon batches. IIRC, he starts running out of mash tun space above 1.100 (for his RIS), and just mashes thicker.
 
Did you brew it yet? How did it go?

Another option might be to get a bag and do BIAB in your 10-gallon kettle. You won't be able to fit the entire volume in there, but you can then pull out the bag and do a dunk sparge in your 8-gallon mash tun, or in a 5-gallon bucket. A dunk sparge is the process I used to get 5.5 gallons of wort for a 1.118 imperial stout a few years ago (using a 10 gallon kettle and a 5 gallon bucket, around 23 lbs of grain I think).

The other option I have used for big gravity beers is to just brew smaller batches. I have done 2.5 to 4 gallon batches doing full volume mash in my 10-gallon kettle. The DME suggestion is also a good one.
 
You didn't mention your intended OG nor did you specify what your normal efficiency was.

One method that nobody else mentioned was to increase your brewhouse efficiency. With a 5 gallon batch size and a brewhouse efficiency of 75% that would be reduced by the large grain bill you are very limited with your current equipment. Raise that to 85% efficiency and you can reduce the grainbill by a fair amount. As you reduce the amount of grain, the efficiency can go up too.
 
Interesting! So per this, I should do as much mash water as possible, but then do 3 full batch sparges?
Sorry to be slow on the response to this question.

It comes down to how much water you want to have to boil off. Figuring out how much water to use works backwards from your target volume to the fermenter.
  • Target Post-Boil Volume = Target Fermenter Volume + BK Trub and Plumbing Losses
  • Target Pre-Boil Volume = Target Post-Boil Volume + Boil-Off Volume
  • Total Brewing Water Volume = Target Pre-Boil Volume + Grain Absorption + MLT Undrainable Volume
You can increase efficiency by increasing your total brewing water, but that forces you to boil off more volume to reach your target post-boil volume.

So, once you know what total brewing water volume you need (can tolerate), you have to decide how many sparge steps you are willing to do, and divide up your total brewing water between strike and sparge(s). You maximize efficiency by having all run-off volumes (initial mash and all sparges) be equal. Being exactly equal is not necessary, as you get an insignificant loss in efficiency as long as the volumes aren't wildly different.

As long as the mash doesn't get too thick to be processed, the math for calculating volumes looks like this:
Strike Volume = Grain Absorption + MLT Undrainable Volume + Pre-Boil Volume / (N + 1)​
Sparge Volume = Pre-Boil Volume / (N + 1)​
Where "N" is the number of sparge steps you intend to do (if N = 0, then you don't bother with the second formula above.)

If the above formulas result in a mash that is too thick for your system, then you need to modify the calculations too keep your mash thin enough. This is more likely to happen with large grain bills (high OG beers.) First you determine the minimum mash thickness you want (in qt/lb) and then:
Minimum Strike Volume [gal] = (Grain Bill Wt * qt/lb) / 4​
Actual Strike Volume = max( Minimum Strike Volume, Grain Absorption + MLT Undrainable Volume + Pre-Boil Volume / (N + 1))​
Sparge Volume [each step] = (Total Brewing Water Volume - Strike Volume) / N​
So for maximum efficiency, you would do an infinite number of small sparges, and then the three formulas above become two:
Strike Volume = (Grain Bill Wt * qt/lb) / 4​
Total Sparge Volume = Total Brewing Water Volume - Strike Volume​
Sparging is done by adding a tiny amount of sparge water, then draining off an equally tiny amount of wort, repeating until you have used all of your sparge water, and finally draining any remaining wort. This is a fly sparge or continuous sparge.

Brewers go to batch sparging because it is less work and faster then fly sparging, and they accept that they will have slightly less than maximum efficiency. You have to decide what the proper trade-off is for time/effort vs. marginal increases in efficiency.

The chart doesn't tell you how you should sparge, it tells you what the effect of different choices are. You still have to make the choice in the paragraph above.

Brew on :mug:
 
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