Will this overflow my mash tun?

[Donasay]

Hey everyone, I am making a big beer this weekend and was looking for some help with the calculations. I usually mash at just one or two temperatures, and I have been doing ok in efficiency. I am going to try a recipe that requires multiple rests, when I do two rests, I usually add hot sparge water to the mash to get it up to the correct temperature and stir. I know not the best technique, but it works for me.

With my big beer and multiple rests I am wondering if I am going to wind up adding to much water to increase the temperature and end the day with an overflowing 10 gallon cooler. I know you guys know the formulas for adding water to bring the mash up to certain temperatures and the formulas that tell you how big the volume of the mash will be at the end.

I am going to be doing a 10 gallon recipe, so a 12 gallon boil, the recipe calls for about 22lbs of grain. If I get my normal efficiency (65 – 70) which is a little low, but decent I might have to throw in another pound or two of two row. The question I have is with the 22lbs of grain and the following mash schedule how likely is it that I will overflow my 10 gallon container?
Protein Rest - 122°F – 30 min
Beta Conversion – 140°F – 15 min
Alpha Conversion - 158°F – 40 min
Mashout - 170°F – 10min

If you guys could also include the formulas you use to figure this out that would be very helpful.

 

[Beerthoven]

Go here: http://www.rackers.org/calcs.shtml

and scroll down to Can I Mash It?

 

[PseudoChef]

You should also be concerned about having too thin a mash. From my understanding, too thin and the enzymes won't be allowed to properly do their job in conversion. Please correct me if I'm wrong.

You could decoct. I know it sounds like a pain in the arse, but it really isn't. I did it for the first time this past weekend...granted just a single decoction. For this, I did my protein rest at 133, then used BeerSmith to calculate what portion of the mash to remove to boil. After you boil, you return that portion of the mash to the MLT to bring the rest of the mash up to temp. It was quite easy, and I'm actually thinking it helped boost my efficiency from the 65% range like you up to 77%.

For instance, I think I had 19.75 pounds for a 9 gallon batch. I infused with 138.5 degree water to hit 133. Rested for 30 minutes, then took off a little over 2 gallons of mash (when you decoct you use the stiff part of the mash -- not as much water/wort, but if you're simply looking to raise the temp and not extract the melanoidins, you could probably just pull your required volume with water/wort and all) and brought it to a boil. I then returned this, and stirred it in to hit 152. It was so much easier than I thought it would be.

Since you're already planning on a step mash, I don't think you're too worried about time.

 

[Donasay]

Thanks, but the calculator does not take into account how much extra water I will need to add to bring the mash up to temperature, so for my initial protein rest if I add 1.25 quarts per pound, I wind up with 8+ gallons, if I add an extra gallon or so (i don't know how much gets added) of boiling water to bring the temp up for the second rest 140 it will be close to overflowing. The second additon of water to get it to the third rest temp (I don't know how much) will most likely overflow it.

I really could use some formulas for figuring this out so I know how much water I will need to add at each stage to get it to the correct temperature.

 

[The Pol]

Without even looking at a calculator, 22lbs of grain and 4 infusions will be impossible. You may want to think about decoction to raise temps if you want to go that many rests... that is the only way with a cooler.

 

[The Pol]

BTW I use the free brew software from Strange Brew... works stellar. But as I said, from experience... youd be lucky to do those rests with 10lbs of grain in a 10 gallon cooler.

 

[The Pol]

Here is your schedule... 14.5 gallons total volume

protien 5 gals at 133.5F
beta 1.7 gals at 205F
alpha 2.7 gals at 205F
mashout 2.6 gals at 205F
Sparge 3.1 gals at 170F

This assumes .9 qt/lb for your initial dough in!!

The best you can do is 15lbs with these rests, that is 9.7 gallons... TIGHTTT

 

[Donasay]

O.K. looks like I'll be cutting back on the grains and using some DME to boost this up. Thanks for lettig me know about the problem looks like I need to actually buy some good brewing software to figure this stuff out. I am currently using freeware and it is not advanced enough to figure out the various water additions and temperatures, so up till now I was just adding hot water and stiring until it got to the proper temperature.

I know there are formulas that you can use to calculate it by hand, but you were so fast at that with the brewing software, that it might be worthwhile for me to spend the 30 bucks.

 

[The Pol]

Took me 30 seconds... took alot longer to type it all in here LOL

 

[malkore]

when doing a multi step mash, you typically dough in very thick (1qt/lb of grain or less). that's what allows you to do your step increases without getting too thin.

 

[WBC]

The thickest mash I have ever done is 25 lbs to 25 qts strike water in my Rubbermaid 10 gallon cooler/mash tun. I would not think I could get any more grain in there as it was 1 inch from the top and was hard to stir. I mashed 90 minutes and I had to drain and sparge 3 times to get all the sugars. I ended up with 15 gallons preboil and boiled down to 12 gallons. The beer was fabulous!

 

[reshp1]

Here is your schedule... 14.5 gallons total volume

protien 5 gals at 133.5F
beta 1.7 gals at 205F
alpha 2.7 gals at 205F
mashout 2.6 gals at 205F
Sparge 3.1 gals at 170F

This assumes .9 qt/lb for your initial dough in!!

The best you can do is 15lbs with these rests, that is 9.7 gallons... TIGHTTT

That seems to line up with my calculations (I made an excel sheet, although I think I might try your program). However, in practice, I seem to always add more water than the calcs say. I think it's because of cooler thermal mass, grain thermal mass changing when it gets wet, water cooling while pouring etc. Anyway, it starts getting away from you exponentially as you try to do more steps since the extra water you add in the previous step is now more thermal mass that needs more incoming water to bring up to the next temp. Like someone mentioned you hit a hard limit when your water to grain ratio get's too high (I think >2.5 qt/lbs starts impacting conversion).