Mash water for decoction

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Beernik

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I might be crazy for considering a decoction mash for my second AG. But I'm thinking about doing an Export befor my cellar gets too warm for lagering.

My question is how many quarts of water per lb of grain should I use. I have one book that recommends 2 to 3 quarts water with 3 quarts being preferable. My other book recommends 1.5 to 2 quarts.

If I do it, I'm only doing a single decoction.

My main concern is I'm planning on using 10.5lbs of grain. That would put me around 7.5 -8 gallons of water and 10.5lbs of grain going into my MLT. My MLT was pretty close to capacity at 7 gallons of water and 10.5lbs of grain during my infusion mash.

Will I be okay going with 2.5 quarts per pound so I can be sure I won't be overfilling my MLT?
 
Beersmith says to add 21 quarts at dough in, which would be 2qt/lb. It says to decoct 9 quarts of mash.
 
I think 2 qts/lb is standard for decoctions. When I did mine I was a little lower at 1.5 qts/lb and it still worked.
 
Cool. I can make 4 - 5.25 gallons work a lot easier than 7.8 gallons. And I'll be able to sparge with a couple gallons too.
 
Lots of recipes that call for decoctions are actually as good with a single infusion mash.

If you post your recipe, maybe one of us experienced "decoctors" can help you out. (That sounds dirty. I'm sorry about that).

I use Beersmith software, and it really helps. The Vienna lager I have in primary right now is a double decoction, and the calculations were right on the money in Beersmith. I easily hit my temperatures, and it went like clockwork.

Remember to pull the decoction from the thickest part of the mash. You want to use the grain, not much of the liquid. Also, when you bring it up to a boil, if you're going to a saccrification temperature, hold the decoction at that temperature for 10 minutes or so before bringing it to a boil, so that you get conversion. If you're doing a single decoction, you can just decoct to mash out temperatures so it's not important, but if you're going from a protein rest temperature to a saccrification rest temperature and it's a sizable decoction, you will want to rest.
 
Please don't decoct me. I promise to behave.

Export apparently isn't as popular as it's cousin Plisner. I haven't been able to find an AG recipe to base mine on yet. Here's my first stab at it:

8.0 lb pilsen
2.0 lb light Munich
0.5 lb crystal 10L

1oz perle 60 min
1oz hallertau 15 min
1oz saaz 1 min

I'll adjust my hops as necessary to have an IBU = 30.

For the mash I was thinking:

1. Mash in at 100F with 21 quarts of water
2. Raise the temp to 122F.
3. Rest for 20 minutes.
4. Pull 9 quarts of mash off, trying to take 2/3 grain and 1/3 liquor and put it in a second pot.
5. Raise the temp of the decoction to 158F.
6. Rest for 15 minutes.
7. Bring the decoction to a boil for 40 minutes.
8. Put it back in the mash, the resulting temp should be 147F. If not, raise heat.
9. Rest for 20 minutes.
10. Raise temp to 158F and rest 20 minutes.
11. Check for conversion.
12. If converted, pour back into MLT.
13. Sparge with additional water to collect 7 gallons.

The main problem I can see coming is that I live at 5500' and water boils at 200F.
 
I just finished making a spreadsheet for decoction mashing. I don't have Beersmith, but I found a website that appears to have the same calculator. My spreadsheet seems to be consistently calculating about 1/2 a quart higher than Beersmith. My calculations don't adjust for the weight of the mash pot, like Beersmith's does.

I might he crazier now because I'm thinking about modifying the recipe into a Bock and doing a triple decoction just so I can check my spreadsheet calcs.
 
I finally did this tonight with a double decoction.

I'm not sure I'm going to ever do that again unless this beer turns out fabulous.

It's like doing two partial boils and following it with an infusion mash to mash out. Then you get to start the main boil. I started prepping at 5pm and finished cleaning at 2am.

Now I'm chugging a Guinness so I can get 3 hours of quality sleep before I have to get up for work tomorrow.
 
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