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General Category => All Grain Brewing => Topic started by: DW on November 10, 2011, 01:00:30 PM

Title: decoction mash
Post by: DW on November 10, 2011, 01:00:30 PM
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? 
Title: Re: decoction mash
Post by: davidgzach on November 10, 2011, 01:07:38 PM
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. 
Title: Re: decoction mash
Post by: hopfenundmalz on November 10, 2011, 01:27:57 PM
Read more about it at braukaiser.com.  Very good information there.
Title: Re: decoction mash
Post by: tomsawyer on November 10, 2011, 02:38:30 PM
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.
Title: Re: decoction mash
Post by: morticaixavier on November 10, 2011, 03:07:06 PM
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.
Title: Re: decoction mash
Post by: weithman5 on November 10, 2011, 03:08:50 PM


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.
Title: Re: decoction mash
Post by: Hokerer on November 10, 2011, 04:57:47 PM
+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.
Title: Re: decoction mash
Post by: hubie on November 10, 2011, 06:00:53 PM
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. ;)
Title: Re: decoction mash
Post by: tomsawyer on November 10, 2011, 06:33:32 PM
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.
Title: Re: decoction mash
Post by: anthony on November 11, 2011, 02:12:28 PM
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  ;D
Title: Re: decoction mash
Post by: denny on November 11, 2011, 02:27:04 PM
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  ;D

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.
Title: Re: decoction mash
Post by: weithman5 on November 11, 2011, 02:29:07 PM

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.
Title: Re: decoction mash
Post by: anthony on November 11, 2011, 03:15:15 PM
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  ;D

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 (http://groups.google.com/group/rec.crafts.brewing/browse_thread/thread/c49d82a74d9daaad/796be5be2d07ce2c) ;)

Ultimately, it is a journey I think every brewer should take.
Title: Re: decoction mash
Post by: denny on November 11, 2011, 03:22:34 PM
I really think that everyone should try it for themselves. I mean... it really wasn't that long ago that you were espousing decoctions (http://groups.google.com/group/rec.crafts.brewing/browse_thread/thread/c49d82a74d9daaad/796be5be2d07ce2c) ;)

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.
Title: Re: decoction mash
Post by: speed on November 12, 2011, 06:41:27 PM
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.
Title: Re: decoction mash
Post by: davidgzach on November 14, 2011, 07:24:41 AM
I think the decoction will prove to be better with darker beers as you get more carmelization from the various flavor/color malts.  I did a triple decoction Oktoberfest this year which was fantastic compared to a very good double infused one.
Title: Re: decoction mash
Post by: DW on November 19, 2011, 08:42:20 AM
It seems, based on the discussion here, that doing a decoction at all is somewhat controversial.  I have never done one.  I generally do single infusions and batch sparge.  It was recommended in this discussion to check out the YouTube decoction video, which I did.  He, the German guy, said that decoctions were better when you have "less modified" malts such as munich.  Do you all agree?  Does it really make a difference? 
Title: Re: decoction mash
Post by: denny on November 19, 2011, 09:37:02 AM
Do you all agree?  Does it really make a difference? 

I very much agree.
Title: Re: decoction mash
Post by: bluesman on November 19, 2011, 11:28:11 AM
I think a decoction mash can make a difference when all of the parameters of the mash are in order. Proper grain (under-modified), proper heating schedule, proper enzyme activity, etc... Pilsner Urquell has it down pat. However, they have been making this beer for decades and have refined their techniques.

Personally, I've found that a decoction mash makes great beer but so does a single infusion mash, supplemented with some specialty malts. The difference to me is not overwhelming, and I believe one can make a beer just as good using any mashing technique (single infusion, step mash, decoction mash) by tweaking the grain bill and mash schedule.

That being said, I recommend trying it (decoction mash) out for yourself. The only way to really understand the effects of a decoction mash is to try it for yourself and compare it side-by-side, via blind tasting, with a single infusion or step mashed beer.
Title: Re: decoction mash
Post by: davidgzach on November 21, 2011, 06:29:04 AM
It seems, based on the discussion here, that doing a decoction at all is somewhat controversial.  I have never done one.  I generally do single infusions and batch sparge.  It was recommended in this discussion to check out the YouTube decoction video, which I did.  He, the German guy, said that decoctions were better when you have "less modified" malts such as munich.  Do you all agree?  Does it really make a difference? 

Agree 100%.