Are you intimidated by the thought of a decoction mash?

I've got to admit, I'm curious about decoction mashes. As I understand it, it's the only way to achieve the kind of rich, malty perfection of a beer like an Ayinger Celebrator. So far, I've only ever done single infusion batch sparge mashes.

But the idea of a decoction mash intimidates me.

I've watched a few YouTube videos on decoction mashes, and the part that I don't get is how you boil some of the grains without burning them. The videos I've watched seem to take both liquid and grains in the decoctions, but what consistency? Is it the same as the main mash? More liquid than grains? More grains than liquid? And why don't the grains scorch onto the bottom of the kettle used for boiling the decoction, creating a messy cleanup and releasing a flood of harsh tannins?

Is anyone else intimidated - yet still intrigued - at the thought of a decoction mash?

sign me up... intimidated and intrigued

i've only done single infusion mashes so far, but am going to tackle a decotion this next beer. from what ive gathered, is when you boil the decotion you want the same ratio as your main mash. and to keep from burning you grain you want to stir it a lot. please someone correct me if i am wrong.

I wouldn't say I'm intimidated, but never really cared to try. Don't they say that for today's well-modified malts you don't really need to do decoction ?

Usually you pull "thick" (mostly grains) for the first few steps, and then "thin" (more liquidy) for the final decoction. If you stir constantly, you won't have any burning, think of it like cooking oatmeal, and don't crank the heat too high. It's not intimidating, it just adds a whole lot of extra time to the brewing process.

I was intimidated by a decoction mash until i tried it. They are not really hard but are alot of work. Yhe reason you dont want alot of liquid is that is where all the enzymes are located to cinvert your mash and if you boil the liquid you will kill them. So to get around this you pull the tick part or the grains. There is still liquid in the grains though and it will come out as you heat it up. So the key to not burning (which is a very real concern btw) is low heat and stiring. You should have a temp increase of around 2-3 degrees per min, no more. So doing the math, going from 130 to boiling should about 40 min (212-130=82 degree rise divide by 2 degrees per min). And you should be stiring it throught that time. So they are alot of work but imho i thing they are worth it you get some flavors that are just not possible to replicate exactly with differnt malts. Btw, when/if you do a decocotionnfor mashout (152ish to 168) you can pull a thin mash and get more liquid because the converstion is complete so it can be rqised quicker. Hope this helps!

Typing on a tablet sucks.....

Not sure if I understand the point in a decoction mash. First, by pulling out liquid and boiling it, you're destroying the enzymes. which kind of is contrary to the whole purpose of malting and mashin. Second, at a time it was used, people didn't have nearly the understanding of malts nor the consistency of modern malts. The modern malting process itself does much of the work a decoction mash was intended to do with the ****ty malts of the past.

I'm all for doing things because they're cool. It's a different way of doing things, it's traditional, etc. I'm not crapping on that aspect of it. I just don't see the purpose of it from a technical point. People will say there's a difference in flavor, but how much of that is placebo, and how much of that is interbatch variations? Probably more than due to the decoction.

Am I missing something here? If I'm mashing to take advantage of the enzymes, why embark on a process like decoction that intentionally destroys the enzymes?

Typically you pull your decoction, do a 15 minute Sacch rest and then boil it, so the enzymes have done their work already, and there's still a lot more enzymes in the main part of the mash. This supposedly helps develop more melanoidins due to the Maillard reactions that take place during the boiling of the decoction.

I believe it's also from the time before thermometers, so by removing and boiling a certain volume, when you add it back to the mash, you raise the temperature through the desired rest temps for conversion. It's a pretty cool technique when you think about it, it also allowed mashing to take place in unfired mash tuns.

I took an advanced brewing class at the LHBS and here's how we did a single decoction:

EQUIP: 3-tier direct fired system, 15 gallon vessels
RECIPE: Maibock, 10 gallons
GRAIN BILL:
20# German Pils
2# Vienna
1# German Wheat
1# Belgian Aromatic
1# Honey Malt
4 oz Acidulated Malt - only used in the 60% grist portion

Split the grist 60/40 into 2 vessels.
60% of the grist is brought to 120F and held there. While this is resting bring the remaining 40% to 158F and hold for 10 min, then raise the temp to boiling and boil for 10 minutes.

By now the first 60% has been resting for about 40 min due to the ramp up and boiling time of the 40%.

Combine the 40% with the 60% which should bring the entire grist to 150-158. Rest here for 90 minutes. We then heated to 165-170 for a 10 min mash off. We then fly sparged.

A great, great thread guys; all the major points on the subject seem to have been covered by someone.

Combining rjsnau's post with BigRob's gives a great understanding of the subject.


It IS kind of scary the first time you do it, and I was definitely afraid of scorching, enzyme destruction, and extracting tannins but worried for nothing.

How much of the mash you pull out, how thick it is, whether you rest at saccrification temps on the way to boiling and how long you boil are actually all variables; the answer is "it depends" what you're trying to do, what ingredients you used as an input, and what style beer you're trying to make.

As others have pointed out you're almost always pulling a fairly thick decocation (use a strainer) and you're definitely stirring when the mash gets close to boiling and through the boiling. The longer you boil each decoction the more color and malliard flavor development that you get so generally darker colored beers (bock) have the decoctions boiled for longer periods of time and ligher beers (Pils, Marzen, Hefe) for shorter periods of time.

Any time that you're pulling a decoction that hasnt' sat through at least a 45 minute sacc rest you need to do the sacc rest on the way to boiling to convert those sugars. -Do it around 68C -70C and you'll get faster conversion. This lets this part of the mash get converted; you're also generally ok on the enzymes as the enzymes have leached out of the grains and are actually in the liquid portion at this point (this is another reason that the decocted portion should be thick - you'll boil and kill fewer enzymes). -This is also why it's not a big deal to decoct a more liquidy decotion to get to mash out temps (conversion is already completed) -you also don't want to boil a lot of grain this late in the process because you might extract a bit more unconverted starch from the grain at this point and then kill the enzymes and add the starch back to a mash that has dead enzymes (mashout quickly dispatches them). On the enzymatic side we're also talking about a german technique that used german malts that are generally pretty high in enzymatic power so the degradion of enzymes isn't a big deal. If you're using pale malt instead of lager malt and tons of speciality malt as in a modern American intepretation of a German beer you COULD run into problems. (I could see an American dunkel bock recipe that utilizes pale as a base malt running into issues with a decoction.)



The traditional profiles are there for a reason and are associated with certain styles of beer for those same reasons.
As far as whether such a profile is necessary; certainly not to get melanoidins and not because modern malt is undermodified but there are some very highly experienced brewers and judges who swear that there is a difference between decoctions and infusions with additions of speciality malts high in melanoidins. (Although there are plenty of experienced brewers and judges who claim the opposite so try it for yourself and come to your own conclusions.)




Adam

highgravitybacon said:

Not sure if I understand the point in a decoction mash. First, by pulling out liquid and boiling it, you're destroying the enzymes. which kind of is contrary to the whole purpose of malting and mashin. Second, at a time it was used, people didn't have nearly the understanding of malts nor the consistency of modern malts. The modern malting process itself does much of the work a decoction mash was intended to do with the ****ty malts of the past.

Am I missing something here? If I'm mashing to take advantage of the enzymes, why embark on a process like decoction that intentionally destroys the enzymes?

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Yes, you're missing something. The decoction volume is taken from the thick mash; mostly grain, with some liquid, but most of the liquid remains behind in the mash tun. The enzymes are in the liquid. Sure, some of the enzymes will be destroyed, but certainly not enough to prevent conversion.

Secondly, there are supposedly other reactions that occur during the decoction that are said to create a more malty flavor. There is a lot of debate on this topic, but many claim an increased malt flavor to decoction brews.

I've done a couple decoctions, mainly "just because"... and it made for a long brew day. My first lager was an Oktoberfest that I decocted, and it was beautiful. Not sure it was worth the extra time investment, but it was still fun.

Great post, Adam, it really answered a lot of my questions. I still have 2 things that confuse me, however:

biertourist said:

As others have pointed out you're almost always pulling a fairly thick decocation (use a strainer)

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How do you boil a "thick" decoction that's been through a strainer? Isn't this basically just a lump of wet grains? How would such a thing actually "boil?" Wouldn't you just get the occasional bubble popping up through the oatmeal-like mass? Maybe this is the sort of thing that will become obvious if I ever actually do a decoction, but intuitively, it just seems like if I tried to boil oatmeal that's been strained of all free liquid, it would just scorch to the bottom of the kettle rather than do anything resembling "boiling."

And how long do you "rest" at sacc temperatures on your way up to boiling with a decoction? Or does it depend on which decoction it is?

kombat said:

Great post, Adam, it really answered a lot of my questions. I still have 2 things that confuse me, however:



How do you boil a "thick" decoction that's been through a strainer? Isn't this basically just a lump of wet grains? How would such a thing actually "boil?" Wouldn't you just get the occasional bubble popping up through the oatmeal-like mass? Maybe this is the sort of thing that will become obvious if I ever actually do a decoction, but intuitively, it just seems like if I tried to boil oatmeal that's been strained of all free liquid, it would just scorch to the bottom of the kettle rather than do anything resembling "boiling."

And how long do you "rest" at sacc temperatures on your way up to boiling with a decoction? Or does it depend on which decoction it is?

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you still have liquid in the decoction and the hotter it gets the thinner it gets. had our brewing forefathers had the variety of malts we have today i don't think they would have bothered with decoctions. i wonder if you could tell the difference between a decontion beer and one that used melanoidin malt instead? i have no idea but maybe someone has experimented with this?

someone did do a comparison: https://www.homebrewtalk.com/f13/decoction-vs-melanoidin-malt-345844/

As I put more thought into seriously considering trying a decoction mash, I came up with another question: How do you maintain the heat in your main mash while you're collecting and boiling decoctions? My cooler MLT can hold temperature for 60 minutes, as long as I keep it closed and wrapped in a blanket. But if I need it to mash for 30 minutes, then open it and remove a decoction, then close it back up for the 40 minutes I'm heating/boiling the decoction, won't it lose significant temperature?

What do you "decocters" do? Do you mash in a kettle to which you can periodically apply heat? Has anyone done decoction mashes with a cooler MLT? How do you maintain temperature in the main mash?

You do have to keep stirring your thick decoction while you're cooking it, and occasionally you'll find some spots that are sticking a bit that you'll want to break loose, but it shouldn't scorch if you stay on top of things.


So far as the MLT logistics go, I put in the strike water, stir it all up to get the temperature equalized, and then IMMEDIATELY pull out the first decoction to get it going. By the time you have heated up your decoction and boiled it for the appropriate amount of time, you should be ready for you next decoction step in the MLT anyway. You will want to slowly raise the temperature in the decoction...if you just turn the burner on full blast you very well could end up scorching it, and the point of the decoction is to slowly bring it up through the amylase temps anyway. So, a couple degrees F per minute is a typical guideline.

Thanks, Weirdboy, that makes sense.

All of the responses in this thread have really helped clarify the idea of decoction mashing for me. This seems to be a topic that is frequently glossed over or ignored completely in brewing literature. I'm currently reading New Brewing Lager Beer, and it has a good section on decoction mashing (though I think I'll need to read it several times for it all to sink in). I would love to try my hand at a Doppelbock, and thanks to the answers you guys have provided, I think I might just take a stab at one later this summer.

Go onto Kai's website (BrauKaiser) and watch his 2 or 3 videos on decocting and read the couple of items that he has on the subject on his wiki page. -It will make you feel much more at ease with decocting. -You will be able to calculate how much grain to pull for each decocation and at which thickness on your own, without a calculator tool, too. (I find it reassuring to be able to at least theoretically understand the process enough that I don't need to just rely upon someone else's calculator or documented process.)

To answer your direct question: The grain holds plenty of liquid so transfer to your decoction pan/vessel with the strainer and then just top it up with liquid so that it's covered. (I just wanted to do a simple single decoction my first time and really just wanted to see if I got a maltier taste -I did a sacc temp to mash-out temp decoction as it takes the least amount of time; this was for a dunkel bock so I gave it a 20 minute boil. It's not a traditional decoction at ALL; you just won't find that profile anywhere but it is an easy way to try a decoction without making your brew day take forever and you have little worry of killing off the enzymes as you don't pull the decoction until after you've finished conversion.)

Don't forget the 15% - 20% "fudge factor" that Kai recommends in his video(s) as it's pretty rough math given all the system to system and mash to mash variables. -I found that the BeerTools calculator had a much smaller fudge factor and I was glad I calculated it on my own; I nailed my temp numbers with my insulated mashtun, anyway.

Also, take a picture of your decocted portion at the beginning then take a picture after 5 minutes, 10 minutes, and so on (depending upon how long you boil the decocted portion). It's pretty amazing how much darkening you get from a 20 minute boil even though you don't realize it while watching it in real time. -You'll quickly understand how an old Munich Dunkel and Dunkel Bock recipe could have used ONLY Munich and Vienna malts and still ended up so dark.

Decoctions don't have to been a pain, although they WILL make the brew day longer I find them super therapeutic as my brewing has become less and less hands on as my system gets more advanced; there's something nice about having a really hands-on decoction brew day. The connection to the tradition, although having no impact on the finished product is also really cool, too. I really appreciate the old German pictures of guys moving grain manually from one vessel to another using wooden buckets attached to poles (or "mash scoops" or whatever they're called.) now.

Adam

P.S. I LOVE, LOVE, LOVE this forum! There's SOO many super super knowledgeable and experienced people; it's fantastic to be able to finally have these sorts of discussions after being stuck in all my brewing books and not having the ability to talk about the finer points with anyone!


Adam

I did my first ever decoction mash on the Hefeweizen that's just about done with primary fermentation (did a double decoction from protein rest to sacch rest to mash out) .

I was mortified at first, but it was a lot easier than I thought it would be. I ran with Palmer's math from How To Brew. He also references lab tests showing that even the thickest possible decoction pull is still about 50% water, so there's plenty to boil. And I learned that the math and calculators aren't going to get it right (both mashing in for the protein rest higher than planned, and increasing the decoction volumes 15-20% more than the math said, and I hit the second rest temp, but fell a degree short of my planned mashout temp), and will generally instruct you to pull less than you actually need. And as many others have said, trick to not scorching your decoction is stirring 100% of the time. Can be a little tough on the arms.

It may well be placebo, but from a gravity sample it certainly tastes maltier than previous Hefes I've done. If I were thorough I'd replicate the recipe with a single infusion mash and do a blind side by side tasting. Perhaps if I rebrew this down the road I'll do it then. There was a tasting done (I don't recall who did it) where the same beer was done with and without decoction, and people chose either decoction, no decoction, or no preference. More folks preferred decocted to non-decocted, but no preference outnumbered both. So it seems it's a contentious issue whether it's really necesary or not.

For what it's worth I used Beersmith to plan my last decoction recipe and it completely nailed the numbers. I hit all my step temps right on the money. That was using my igloo ice cube MLT and a small 4 gallon pot for the decoctions. I use a cheapo $1 plastic pitcher that has measurements down the side to pull out the mash, so that it's easy to keep track of my decoction volume.

weirdboy said:

For what it's worth I used Beersmith to plan my last decoction recipe and it completely nailed the numbers. I hit all my step temps right on the money. That was using my igloo ice cube MLT and a small 4 gallon pot for the decoctions. I use a cheapo $1 plastic pitcher that has measurements down the side to pull out the mash, so that it's easy to keep track of my decoction volume.

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I ran it through Beersmith too, and all the numbers roughly jived with Palmer's formula. I'm assuming that because I mash in a kettle, it was temp loss. I expected it and tried to account for it, hence the larger pulls. Glad I did. But the point here is that the actual decoction volumes you need are going to be equipment-specific.

I usually do triple decoctions on pilsners, doubles on hefe's, light and dark, and I always do decoction mash outs. I usually pull thin decoctions to minimize scorching and have never had an issue. If anything my efficiency goes up with all the torturing the grist goes through. I'd bet there isn't much of a difference outside of a maltier and slightly darker beer. I just do them because it lengthens my brew day/zen time and they are fun once you get used to them.

I've done it twice and each time I've viewed it as an experiment. Not too concerned with the results more so just getting the process down. That said, my Oktoberfest was great!

I did a double decoction on my first-ever Hefeweizen last year (this one), and while it's cool to be able to say I've done one, I don't think I would do it again.

One of the much-debated topics re: decocting is why to bother with it when modern malts are so well modified. One aspect of the debate is the necessity of the protein rest, and my experience actually gave me a side in the debate: my Hef had absolutely terrible head retention, and I'm pretty sure it's because I did an unnecessary protein rest; the purpose of the rest is to break down proteins, and proteins are responsible for head retention. Everything else about the beer (banana/clove taste, mouthfeel, color, turbidity, etc.) was great, but it would lose its head in less than a minute.

I'm going to re-brew the Hef this year and sub in a pound or so of melanoidin malt instead of decocting, to see once and for all whether the poor head retention was a fluke.

-Rich

eastoak said:

someone did do a comparison: https://www.homebrewtalk.com/f13/decoction-vs-melanoidin-malt-345844/

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And I did an experiment comparing decocted to non decocted beers. The result after a blind tasting was that there was not a preference for the decocted beers. The results start here on pg. 25

http://518124.cache1.evolutionhosting.com/wp-content/uploads/presentations/2008/DennyConn.pdf

Denny said:

And I did an experiment comparing decocted to non decocted beers. The result after a blind tasting was that there was not a preference for the decocted beers. The results start here on pg. 25

http://518124.cache1.evolutionhosting.com/wp-content/uploads/presentations/2008/DennyConn.pdf

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Ahhh....this was the experiment I referenced earlier. I incorrectly recalled the specifics, but at least I had the overall conclusion right