decoction mash

[DW]

Does anyone have much experience with decoction mashing?  I saw a recipe in "Recipe of the Week" called "Tara's Slam" that uses a decoction mash.  It seems strange to me, if I understand correctly: you set the mash at a low mash temperature, pull off a small % of the runnings, heat it up and let that sit for a little whille, then boil that small run off and add it back to the main mash thereby raising it's temp up to a higher rest......and so on.  Did I get that right? 

[davidgzach]

Not exactly.  You pull the thick portion of the mash and boil it.  You do not want to boil the runnings as you will denature the enzymes.  Think boiling the soaked grain.  You then return the decoction after the boil back to the mash to raise it to the next mash step.  Like 131 to 146 to 158 to 167 or mash out.  Then sparge and boil as normal. 

[hopfenundmalz]

Read more about it at braukaiser.com.  Very good information there.

[tomsawyer]

You also want to let the thick decoction have time to convert prior to boiling, so you'll typically let it sit at 155F for 20-30min befor ebringing it to a boil.

And its not really a small amount you pull for a decoction, its quite a bit of material.

[morticaixavier]

You also want to let the thick decoction have time to convert prior to boiling, so you'll typically let it sit at 155F for 20-30min befor ebringing it to a boil.

And its not really a small amount you pull for a decoction, its quite a bit of material.

right. I have heard one qt of thick mash per lb of grain.

[weithman5]

And its not really a small amount you pull for a decoction, its quite a bit of material.

+1. if you leave 2/3 at 150 (2x150= 300) and 1/3 raised to boiling (about 210)  this equals 3 units at about 510 which averages to about 170.  sooooo yes it is not just a little amount. in addition, the specific heat capacity of just pulling some of the wart is significantly different that of the saturated grain and likely won't contribute to raising it as much as you think.

[hokerer]

+1. if you leave 2/3 at 150 (2x150= 300) and 1/3 raised to boiling (about 210)  this equals 3 units at about 510 which averages to about 170.  sooooo yes it is not just a little amount. in addition, the specific heat capacity of just pulling some of the wart is significantly different that of the saturated grain and likely won't contribute to raising it as much as you think.

Not quite sure if it's what you were trying to say with your last sentence but, since the 1/3 you pull for the decoction is supposed to be "thick", it means its grain/liquid ratio is much higher than the remaining 2/3.  Because of the different heat capacities of grain vs liquid, it won't contribute the full one-third towards raising the mash temp when added back in.

[hubie]

I enjoy decoction on occasion.  It does take longer, but the process is pretty easy.  Before I dough in, I get an estimate of how much volume of grain I have.  The first few times I did this when adding the grain to my cooler.  When adding the grain, I did it by the pot full to get an idea of how many pots it took.  Then, when time to pull a decoction, I would use the same pot and pull about a third of it (e.g., if I started out with 10 pots in the mash tun, I'd pull about 3.5 pots for the decoction).  I usually seem to undershoot because it isn't unusual for me to be lower in temp than expected (which is why I have my teapot filled with near-boiling water when returning my decoction).  Every time I tell myself I'll pull a bit more the next time, but then I forget.  It isn't hard to see why I come in low because that 10 pots of dry grain is really larger than that when wet.

Check out Kai Troester's decoction page:  http://braukaiser.com/wiki/index.php?title=Decoction_Mashing
At the bottom of that page he has some YouTube links showing him doing a decoction brew session.

The last time I did a decoction, I did an American Wheat using a hochkurtz double decoction.  The recipe was 50/50 wheat and 2-row.  I entered it in a competition and got the dreaded "not to style" with the comment that I used too much crystal malt in it.

[tomsawyer]

No doubt about it, a decoction is going to give you more body and a higher FG.  Its the bigger part of the OG boost.

[anthony]

No doubt about it, a decoction can give you more body and a higher FG.  Its the bigger part of the OG boost.

I fixed that for you! A decoction alone isn't a silver bullet to do those two things. And incorrectly done, you could make a more fermentable wort using a decoction versus a single infusion alone. It is all about the parameters of course.

Once you start applying absolutes, you're really tempting the decoction opponents to jump in here  

[denny]

No doubt about it, a decoction can give you more body and a higher FG.  Its the bigger part of the OG boost.

I fixed that for you! A decoction alone isn't a silver bullet to do those two things. And incorrectly done, you could make a more fermentable wort using a decoction versus a single infusion alone. It is all about the parameters of course.

Once you start applying absolutes, you're really tempting the decoction opponents to jump in here  

Or, like many people, you may not be able to detect any difference at all.  And FTR, I'm not a "decoction opponent".  I've just done some experiments that make me question its value.

[weithman5]

Not quite sure if it's what you were trying to say with your last sentence but, since the 1/3 you pull for the decoction is supposed to be "thick", it means its grain/liquid ratio is much higher than the remaining 2/3.  Because of the different heat capacities of grain vs liquid, it won't contribute the full one-third towards raising the mash temp when added back in.

sort of. mostly just trying to demonstrate that a)pulling wort alone won't carry back the heat that the grist will and 2) it takes a decent amount to remove and heat up to increase the temperature.  i think too many people underestimate the amount they need to pull.

[anthony]

No doubt about it, a decoction can give you more body and a higher FG.  Its the bigger part of the OG boost.

I fixed that for you! A decoction alone isn't a silver bullet to do those two things. And incorrectly done, you could make a more fermentable wort using a decoction versus a single infusion alone. It is all about the parameters of course.

Once you start applying absolutes, you're really tempting the decoction opponents to jump in here  

Or, like many people, you may not be able to detect any difference at all.  And FTR, I'm not a "decoction opponent".  I've just done some experiments that make me question its value.

I really think that everyone should try it for themselves. I mean... it really wasn't that long ago that you were espousing decoctions

Ultimately, it is a journey I think every brewer should take.

[denny]

I really think that everyone should try it for themselves. I mean... it really wasn't that long ago that you were espousing decoctions

Ultimately, it is a journey I think every brewer should take.

I agree that everyone should try for themselves.  That's ultimately what I did _after_ I made that post.  I had 2 batches of pils around, one decocted and the other not.  After drinking a glass of the decocted pils, I went back for another.  I accidentally got the one that wasn't decocted, but didn't realized it until after I'd finished it, thinking how great the decoction made the beer.  When I eventually realized it wasn't decocted, I started experimenting and comparing.  I still do decoctions occasionally to see if I'm missing anything.  So far, I can't say that I am. But I wouldn't tell anyone to not do it.  Just be sure that you evaluate the results objectively and carefully.

[speed]

i did a triple decoction on a bock awhile back and it was very good but next time i think i will just use melanoidin malt, be a hell of alot easier.