What I don't understand about decoctions...

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wildwest450

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Im doing a pilsner on Friday and want to try a single decoction. I'm using the one on Kaisers page. Protein rest at 130F for 20 min, infusion to get to 150f for 45 minutes, then decoction to get to mashout.

The directions say to let the 150f rest convert for 45min then draw mash and bring to boil (10 to 15min) then boil for 10-30min depending on wort color (im doing it for 10min). That adds 25 to 30 minutes to the mash, in which time im going to lose a degree or two in the mash tun, and add obviously a lot of time to the rest. Is this sop? Or do you pull decoction right away after 2nd infusion and try to time it out that way?

I can see no way to hit mashout temps with the additional time for decoction/heat loss.:confused:
 
The thing I don't understand about decoctions is pulling a portion of the grains out to boil, yet then always learning not boil your grains because of astringency :drunk:
 
The thing I don't understand about decoctions is pulling a portion of the grains out to boil, yet then always learning not boil your grains because of astringency :drunk:

I don't get that either. But after brewing Kais German Alt, I would pee in my beer if he told me to.
 
You'll probably have to pull a decoction that's 'too big' to hit your target mashout temp anyway otherwise you risk not getting up to your target temp. I think Kai recommends this (i.e. pull a decoction that's a little bigger than you'll need). So that extra decoction volume should allow you to make up for the lost heat in the mash. You could even use a small portion of the decoction to adjust the mash temp, or use a quart or two of simmering water to adjust it (I always do the latter anyway).

But I too have sort of struggled with all the extra time the mash is sitting there at certain rest temps. I might pull that decoction at 20-30 minutes but if Kaiser's directions say to go 45 minutes I'd be hesitant to deviate too much. If you pull it early you might want to pause at ~160* F to get more conversion before boiling.
 
When I pull a decoction I get the mash temp where I want it & pull the decoction right away, but I've always done double decoctions. Leaving the mash a little while longer while you're boiling the decoction shouldn't matter even if the mash drops a few degrees. You've done the bulk of your extraction by that point anyway. I keep boiling water handy to raise the mash temp if the decoction doesn't get it to the right temp. It's usually within 5F. I just subtract the extra water from the mash out or sparge water. It's really not all that complicated. I normally get ~82% with a normal mash. Double decoctions always give me ~92% so keep that in mind too.

As far as boiling grains. This atricle from BYO should put you mind at ease: http://***********/stories/wizard/a...you-boil-part-of-your-mash-during-a-decoction:mug:
 
The thing I don't understand about decoctions is pulling a portion of the grains out to boil, yet then always learning not boil your grains because of astringency :drunk:

Wait, you boil the grains? I thought you pulled some wort out and boiled that...

And here I am worried about sparging too hot...
 
The thing I don't understand about decoctions is pulling a portion of the grains out to boil, yet then always learning not boil your grains because of astringency :drunk:

Yeah, I never understood that either. I just did my first all-grain yesterday, but I'll probably be venturing into decoction territory when I brew the wee heavy I've been pondering for the last week. As far as tannins go, they are a pretty diverse group of chemicals and I have no clue what kind are present in barley husks. Everything I've read about tannins and brewing has to do with temperature and pH. Their solubility increases with increasing pH and at temperatures >170F. Maybe you acidify the wort before you do a decoction? I'm just guessing.
 
Oh... A couple more noteworthy points. I use a strainer from the kitchen to pull the "thick mash". Then adjust it with some wort to get the right consistency. You don't want it too thick or it will burn, or too runny and you'll miss out on the benefits of the decoction.

If you're doing a triple decoction you can pull some clear wort, heat it up & use it for your mashout.
 
Yeah, I never understood that either. I just did my first all-grain yesterday, but I'll probably be venturing into decoction territory when I brew the wee heavy I've been pondering for the last week. As far as tannins go, they are a pretty diverse group of chemicals and I have no clue what kind are present in barley husks. Everything I've read about tannins and brewing has to do with temperature and pH. Their solubility increases with increasing pH and at temperatures >170F. Maybe you acidify the wort before you do a decoction? I'm just guessing.

Did ya read the BYO article I posted earlier? :confused:
 
Oh... A couple more noteworthy points. I use a strainer from the kitchen to pull the "thick mash". Then adjust it with some wort to get the right consistency. You don't want it too thick or it will burn, or too runny and you'll miss out on the benefits of the decoction.

If you're doing a triple decoction you can pull some clear wort, heat it up & use it for your mashout.

Thanks for the info! I guess i'll have to wing it on the thickness part.:mug:
 
You'll know if it's getting to thick when you're boiling it because it will blurp rather than bubble. If it does just add a cup or two of wort to thin it out.
 
Using a kitchen strainer is a great way to get a thick mash. Kaiser mentions this in his video. If you want to pull a thin, all-liquid decoction and don't have a false-bottom/manifold/valve you can just press a collander into the mash and scoop from inside the collander.

Also, if you want to get a thick decoction up to a higher temp fast you can pull the uber-thick decoction, then infuse the decoction with simmering water to both thin it out and increase the temp (be careful of pH when doing this though).

Lots of ways to skin this cat, sometimes just deciding on one is the hardest part.
 
Did ya read the BYO article I posted earlier? :confused:

I read that and All I got was that this guy was guessing and that he had talked to a more knowledgeable brewer but didn't speak german and his best guess was that the guy was saying the exact opposite of what the beginning of the article's "guess" was. So no, not exactly clearing things up for me :D
 
I'm confused here. Kaiser is indicating that a single decoction is typically a decoction to mash-out while Greg Noonan indicated a single decoction is from a protein-related rest range to a saccharification/dextrin rest range. The reasons being:

-Thick decoctions are pulled and heated to a rest at ~158°F for about 10 min before heating to boiling. This allows alpha-amylase enzymes to break down long chain dextrins and native starches to smaller constituents that will be further broken down when put back into the mash.

-In addition to melanoidin production, the boiling of the thick decoction bursts open the cell walls in the malt so that more starches and long chain dextrins are available when reintroduced to the mash for further break-down. (This reason and the above reason are why decoction mashes have greater efficiency.)

-For mash-out decoctions, since conversion has already taken place, you're trying to minimize grain boiling, therefore you want a thin decoction. Since mash-out decoctions are thin, the main purpose of them is to get the temperature up to mash-out. So, an infusion or direct-heat mash-out would practically serve the same purpose.
 
I read that and All I got was that this guy was guessing and that he had talked to a more knowledgeable brewer but didn't speak german and his best guess was that the guy was saying the exact opposite of what the beginning of the article's "guess" was. So no, not exactly clearing things up for me :D



"You see, by boiling the grain, starches dissolve and insoluble proteins are denatured and coagulate as a scum on the top. The vital amylase enzymes are quite soluble, so if a "thick" decoction mash is pulled for boiling, the "thin" rest mash contains almost all of the enzymes where they are safe from heat degradation. When the decoction is added back, the dissolved starches are immediately available for the enzymes in the rest mash to go to work on, and the rest mash temperature is raised. The proteins that coagulate in the decoction are usually skimmed off the top before the decoction is added back to the rest mash, which improves wort clarity."


In case you don't want to read the whole page! Makes sense to me.
 
Oh yea, that coagulated protein scum...that will end up on top of your grain bed when lautering/sparging and can prevent good flow through the bed. I def get the coagulated protein cap but haven't had any channeling/flow problems.
 
I'm confused here. Kaiser is indicating that a single decoction is typically a decoction to mash-out while Greg Noonan indicated a single decoction is from a protein-related rest range to a saccharification/dextrin rest range. The reasons being:

-Thick decoctions are pulled and heated to a rest at ~158°F for about 10 min before heating to boiling. This allows alpha-amylase enzymes to break down long chain dextrins and native starches to smaller constituents that will be further broken down when put back into the mash.

-In addition to melanoidin production, the boiling of the thick decoction bursts open the cell walls in the malt so that more starches and long chain dextrins are available when reintroduced to the mash for further break-down. (This reason and the above reason are why decoction mashes have greater efficiency.)

-For mash-out decoctions, since conversion has already taken place, you're trying to minimize grain boiling, therefore you want a thin decoction. Since mash-out decoctions are thin, the main purpose of them is to get the temperature up to mash-out. So, an infusion or direct-heat mash-out would practically serve the same purpose.



Ah, the monkey wrench, now what? I just wanted to try a single decoction to hopefully improve my pilsner, I don't care where in the process it takes place, just the optimal place.:confused:
 
Didn't see your post mensch when I made the two posts above. I thought the same thing, a associate a mash-out decoction with 'all-liquid' and other decoctions earlier in the schedule as thick. Anytime I pull a thick decoction and boil it I want to add it back to the mash before mashout.

WW, you could dough-in to hit acid rest temps (~100* F), immediately pull a thick decoction, quickly convert it (doesn't have to be iodine negative, you just need some sugars in there, you'll convert it all later), boil it, and add it back. You can stay at acid rest temps for quite a while (hours) and the extra acidification will prob do your Pils good. The problem here is getting from 100* F all the way up to your sacc rest temp. Your seeing the same problem many homebrewers have: those protein and beta-amylase rests are very time dependant and getting the decoction converted and boiled within the allotted time can be challenging.
 
Kai recommends the first rest at 129f to 133f, would it be better to decoct here to reach the 150-152 im shooting for? Then just do an infusion to mashout.
 
Here's what I'd do... If you're hell-bent on a protein rest do it for 10 minutes & bump it up to your next rest with boiling mash water & hold for 20 minutes. Pull your decoction. Raise the decoction to ~154F & hold for 15 minutes. Raise to 165F & hold for 10 minutes. Raise to boil & boil for 20 minutes. Add back to your mash for mash out. Stir it in good & run off & sparge as usual.
 
All I'm saying is the grains today are highly modified and really don't require a protein rest. More that 10 minutes may be detrimental to your brew (no head). Personally, I'd skip it.
 
All I'm saying is the grains today are highly modified and really don't require a protein rest. More that 10 minutes may be detrimental to your brew (no head). Personally, I'd skip it.

I was going by this.

"Calculate your strike water to aim for a protein rest between 53 and 55 *C (129 - 133 *F) at a mash consistency of about 2.5 l/kg (1.2 qts/lb). This temperature puts emphasis on the protein degrading enzymes that produce the medium chained proteins which are good for head retention and mouth feel. The well-modified modern malts already have enough short proteins (amino acids) and a rest closer to 50 *C (122 *F) is not necessary."
 
Ahhh.. I was thinking the 122F protein rest. Skipped right over your post earlier about 129-133F. Carry on....

Then you might want to mash in @ ~130F. Do a step to 150-152F, hold for 20 minutes & then pull your decoction.
 
Here's what I'd do... If you're hell-bent on a protein rest do it for 10 minutes & bump it up to your next rest with boiling mash water & hold for 20 minutes. Pull your decoction. Raise the decoction to ~154F & hold for 15 minutes. Raise to 165F & hold for 10 minutes. Raise to boil & boil for 20 minutes. Add back to your mash for mash out. Stir it in good & run off & sparge as usual.
Allowing ~5 minutes for each 'raise temp' and 10 minutes for getting to the boil; that's just over an hour to do that one decoction not counting the 'pulling' part or 'mixing it back in' part.

WW, it can be frustrating to get so many answers but there's just so many ways to do it and everybody has their preferences. And like anything else we got our preferences by trying/struggling/failing and then trying again. My method is to dough-in really thick, pull it immediately, and then infuse the decoction to get it to 158* F (fastest conversion temp), only rest it for 10 minutes max, then straight up to boiling. Doing this you could do that decoction above in about 30 minutes.
 
SCA... My brew day is 2 hours longer when I do double decoctions. I don't mind it so much because the results are fantastic & the beers are scoring very well...
 
I do appreciate all the help. I just need to get a plan and stick with it. I'm not deterred by long brew days. My last dopplebock took almost 8 hours, it was a crazy 6 infusion Zymurgy recipe.:mug:
 
You did that Dopplebock mash! I read that and thought wow, that's a long mash!

PinkyOFloyd, I didn't want to come across as bashing your way, I just felt it necessary to point out the total time since it adds up quick and those rests are time dependant. You obv know what you're doing and heck, we don't homebrew because it saves time anyway!
 
You did that Dopplebock mash! I read that and thought wow, that's a long mash!

PinkyOFloyd, I didn't want to come across as bashing your way, I just felt it necessary to point out the total time since it adds up quick and those rests are time dependant. You obv know what you're doing and heck, we don't homebrew because it saves time anyway!

Cheers man!!!! :mug:
 
I do appreciate all the help. I just need to get a plan and stick with it. I'm not deterred by long brew days. My last dopplebock took almost 8 hours, it was a crazy 6 infusion Zymurgy recipe.:mug:

I think the most effective single decoction for a Pilsner with typical Pilsner malt would be to go from the upper 130s°F or the lower 140s°F and decoct up to the mid to upper 150s°F. Then just infuse up to mash-out (or direct-heat if you can).

You can play with the numbers a little to get a balance between decoction volume and wort profile (proteins/fermentability), but a good example would be: mash in at ~138°F, wait 5 min., pull decoction, heat decoction to 158°F and rest for 10 min., boil decoction for 5 min. (you want a light wort color for a Pilsner), return decoction to main mash, rest at ~158°F for 20 to 30 min, then mash-out however you like.
 
I think the most effective single decoction for a Pilsner with typical Pilsner malt would be to go from the upper 130s°F or the lower 140s°F and decoct up to the mid to upper 150s°F. Then just infuse up to mash-out (or direct-heat if you can).

You can play with the numbers a little to get a balance between decoction volume and wort profile (proteins/fermentability), but a good example would be: mash in at ~138°F, wait 5 min., pull decoction, heat decoction to 158°F and rest for 10 min., boil decoction for 5 min. (you want a light wort color for a Pilsner), return decoction to main mash, rest at ~158°F for 20 to 30 min, then mash-out however you like.

Thanks for the suggestion!
 
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