Decoction Schedule

[cmerritt942]

I have been all grain brewing for a few years and I want to try a decoction mash, but I am having difficulty coming up with a schedule. I use BeerSmith but I brew with a cooler for a mash tun and a pot. The schedule it gives me to mash out is to raise the temp of the mash to 168 over 10 min. I can't heat my mash without adding more water. Any tips would be appreciated.

 

[MrHadack]

I can't heat my mash without adding more water. Any tips would be appreciated.

Sure you can-- how did you perform the other steps? Remove a specific amount of the mash to a kettle, boil, put back in the mash tun. There are calculators that will tell you how much you need to remove and boil.

For example, let's say you have a mash of 12 pounds of grain using 3.75 gallons of water and it is at 153F. You can pull out 1.2 gallons of the mash, boil it, and throw it back in and you should raise the total temp up to 168F.

 

[BigEd]

Not quite sure what you are asking here. A decoction mash raises the temperature by removing a portion of the main mash (the decoction "pull"), boiling that portion, and then adding it back to the main mash. Raising the mash to mash out temp of 168F can be accomplished by any means. Either a decoction step, hot water infusion, direct heating, or RIMS/HERMS methodology can be used to get to the mash out step.

 

[cmerritt942]

MrHadack where can I find a calculator? That was the main problem I was running into, not knowing how much to pull to heat for the mash out.

 

[GoeHaarden]

Someone feel free to correct me here, but pulling volumes for decoction doesn't have to be exact. Somewhere in the neighborhood of 1.25qt per gallon (of the thickest part) or roughly 1/3 the total mash volume is what I have done...but I use decoctions very rarely and so my experience in limited.

EDIT: I add back a portions of the decoction at a time until I hit my desired temp.

 

[brewbama]

MrHadack where can I find a calculator? That was the main problem I was running into, not knowing how much to pull to heat for the mash out.

http://www.franklinbrew.org/tools/decoction2.html

http://beersmith.com/help2/index.html?decoction_tool.htm

 

[BigEd]

Someone feel free to correct me here, but pulling volumes for decoction doesn't have to be exact. Somewhere in the neighborhood of 1.25qt per gallon (of the thickest part) or roughly 1/3 the total mash volume is what I have done...but I use decoctions very rarely and so my experience in limited.

EDIT: I add back a portions of the decoction at a time until I hit my desired temp.

One third by weight, not volume, is a better measurement. I think that's a reason why so many people seem to come up short on temperature when first attempting a decoction mash. Even the 1/3 rule of thumb is a bit short much of the time. I use 40%. Your equipment and technique also factor in so whatever you do it's common to experience some trial & error runs until you get the hang of it.

 

[Yooper]

Also, keep in mind that while for the acid/protein/saccrification rests, you pull the thickest part of the mash. For the mashout decoction, you can simply pull wort (or mostly wort) up to the next step if that works for you since your goal is to denature the enzymes anyway.

Normally, when I do a decoction (not that often these days), I'll do a higher temperature protease rest at 131-133F and immediately pull the decoction so that I don't stay at that temperature unnecessarily long. From there I go to 148 or so. So it's not a big temperature jump compared to some rest temperature differences. Then I pull the next decoction, again mostly grain, to the next temperature rest after about 30 minutes, and then do the mashout decoction after that rest.

 

[GoeHaarden]

One third by weight, not volume, is a better measurement. I think that's a reason why so many people seem to come up short on temperature when first attempting a decoction mash. Even the 1/3 rule of thumb is a bit short much of the time. I use 40%. Your equipment and technique also factor in so whatever you do it's common to experience some trial & error runs until you get the hang of it.

Probably why I don't really utilize decoctions. Hah. Plus, it just seems like it makes brew day unnecessarily longer, but that just could be due to my unfamiliarity with it and not having a perfect process.

Anybody out there do decoctions religiously? If so, can you really tell a difference between decoctions and step mashing? Essentially, isn't it just a primitive way of achieving the same thing? Again, excuse my inexperience with decoctions.

 

[Yooper]

Probably why I don't really utilize decoctions. Hah. Plus, it just seems like it makes brew day unnecessarily longer, but that just could be due to my unfamiliarity with it and not having a perfect process.

Anybody out there do decoctions religiously? If so, can you really tell a difference between decoctions and step mashing? Essentially, isn't it just a primitive way of achieving the same thing? Again, excuse my inexperience with decoctions.

Some brewers have done blind taste trials, and found that there is no difference between a single infusion mash or a step infusion or a decoction in the final flavor.

Others, like me, really feel that the maillard reactions that happen in a decoction do make a difference in the final beer.

A step infusion doesn't boil the grain, so you don't get the flavors that boiling the grain (those maillard reactions) provide. Think of the difference in flavor between bread and toast- those browning reactions are the maillard reactions.

 

[GoeHaarden]

Some brewers have done blind taste trials, and found that there is no difference between a single infusion mash or a step infusion or a decoction in the final flavor.

Others, like me, really feel that the maillard reactions that happen in a decoction do make a difference in the final beer.

A step infusion doesn't boil the grain, so you don't get the flavors that boiling the grain (those maillard reactions) provide. Think of the difference in flavor between bread and toast- those browning reactions are the maillard reactions.

Are we talking warm bread fresh out of the oven with butter on it vs toast? Joking. But, I feel like I've read an XBMT about this and the panel wasn't able to distinguish between decoctions and infusion mashes. I've never done a side-by-side so I honestly couldn't say one way or another.

Yooper, what percentage of brews would you say you do decoctions on?

 

[geoffey]

Anybody out there do decoctions religiously? If so, can you really tell a difference between decoctions and step mashing? Essentially, isn't it just a primitive way of achieving the same thing? Again, excuse my inexperience with decoctions.

Keep in mind who your target audience is. If you're brewing this beer for a serious competition with the end goal being to medal in a specific category then the judges tasting your beer may have pallets that can taste the difference. (They also could not, depends on the judge). So that decoction mash could put you over the top.

But not everyone can taste the difference. So if you're intended audience for the beer is you and your friends, and you prefer to keep brew day short and less complicated, then I'd argue that a decoction mash doesn't likely gain you much.

It may be worth going through a decoction mash at least once as a homebrewer just to get a sense of what it's all about. Some friends at NHC gave me 20 lbs of pilsner grain they'd picked up at the show but made me promise to triple decoct it. So I have that to look forward to soon.

 

[GoeHaarden]

But not everyone can taste the difference. So if you're intended audience for the beer is you and your friends, and you prefer to keep brew day short and less complicated, then I'd argue that a decoction mash doesn't likely gain you much.

It may be worth going through a decoction mash at least once as a homebrewer just to get a sense of what it's all about. Some friends at NHC gave me 20 lbs of pilsner grain they'd picked up at the show but made me promise to triple decoct it. So I have that to look forward to soon.

Well, the number of brew days I will be able to have is about to decrease dramatically so I'm about to brew lagers exclusively so I can leave them if need be. Maybe it's a good time to start practicing decoctions...

For you decocting veterans and back to the OP's questions. Do you usually pull your decoctions, boil, and then re-add a little at a time until you reach the temp you want? Or do you pull a specific/calculated amount, boil, and dump it all back in to hit your temps?

 

[TheMadKing]

One easy option for a decoction without really lengthening your brew day is a simple single mash-out decoction.

Since modern malts are very well modified, the first two decoctions (designed to make starch more accessible to enzymes) are not really necessary. So all you should be after with a decoction mash is the maillard reactions and that "certain I don't know what" that decoction is said to produce.

I do a single mash out decoction on most of my german beers because it's easy and at most it adds 30 minutes to my brew day. Here's my process:

-infusion mash as normal to the 40 minute mark.
-Eyeball a pull-off of roughly 1/3 of the mash, making sure to take a good hearty amount of grist
-Boil it for 10-30 minutes (chef's choice)
-Add it back to your main mash in increments until your mash out temp is reached (165-175)
-Rest an additional 5-10 minutes, and lauter as normal

I like this method because it's very inexact, since the only thing you're going for is a mash out temp and the maillard reactions, so the amounts don't matter too much, and it really only extends your mash by 30 minutes at the most.

 

[GoeHaarden]

I do a single mash out decoction on most of my german beers because it's easy and at most it adds 30 minutes to my brew day. Here's my process:

-infusion mash as normal to the 40 minute mark.
-Eyeball a pull-off of roughly 1/3 of the mash, making sure to take a good hearty amount of grist
-Boil it for 10-30 minutes (chef's choice)
-Add it back to your main mash in increments until your mash out temp is reached (165-175)
-Rest an additional 5-10 minutes, and lauter as normal

Let's say you hit your temp with only using half or what you pulled for decoctions. What do you do with the rest of what you pulled? Stir until the temp drops to close to the temp of the main mash?

 

[TheMadKing]

Let's say you hit your temp with only using half or what you pulled for decoctions. What do you do with the rest of what you pulled? Stir until the temp drops to close to the temp of the main mash?

Yep exactly right, another option is to add some cold water to it to drop the temp, since you likely boiled off a fair amount during the decoction boiling. A third option (and my preferred) is to drop a sanitized frozen waterbottle into it until it's at mash out temp and then dump it back into the main mash. I usually overbuild my strike water slightly to account for the boil-off from decoction.

I use BIAB, no-sparge, so my strike water is approximately the same as my boil volume. If you are on a traditional 3-vessel system, you can account for the boil off with your sparge water, or add top-up water after the boil as well.

 

[Yooper]

Well, the number of brew days I will be able to have is about to decrease dramatically so I'm about to brew lagers exclusively so I can leave them if need be. Maybe it's a good time to start practicing decoctions...

For you decocting veterans and back to the OP's questions. Do you usually pull your decoctions, boil, and then re-add a little at a time until you reach the temp you want? Or do you pull a specific/calculated amount, boil, and dump it all back in to hit your temps?

I don't do many anymore, since I love my electric HERMS and I'd have to take the decoction to the stovetop to do it (and I don't do many German lagers and never a hefeweizen), but when I do them, the calculations from Beersmith and my system are generally spot on and I don't add incrementally.

A couple of keys- if you are doing a protein rest, don't do it for long at all. Pull the decoction immediately, so you don't degrade the protease too much. I really recommend doing the protease rest at a higher temp than some, like 131-133F, and keeping it as short as possible. Otherwise, skip it and go with two saccrification rests (the beta and the alpha amylase rests), and then a mashout decoction if you'd like.

 

[GoeHaarden]

Interesting, still a little conflicted. Seems like more and more people are reserving decoctions for special occassions. I might practice on the next couple of batches...

As always, thanks for the education everyone.

 

[triethylborane]

Probably why I don't really utilize decoctions. Hah. Plus, it just seems like it makes brew day unnecessarily longer, but that just could be due to my unfamiliarity with it and not having a perfect process.

Anybody out there do decoctions religiously? If so, can you really tell a difference between decoctions and step mashing? Essentially, isn't it just a primitive way of achieving the same thing? Again, excuse my inexperience with decoctions.

I do decoction mashes for about 1/3 of my batches as I tend brew a lot of hefeweizens, weiss, dunkels and bocks, including weizenbocks. As you might notice, quite a few are wheat beers. Wheat beers can benefit from a decoction mash as wheat proteins are complex viscoelastic (mostly gluten) chains that can withstand high temperatures without denaturing or lysing. A decoction mash is what will break down the wheat protein into shorter chains of amino acids that are beneficial for yeast reproduction. Likewise, wheat starches are broken down in a decoction that can react with the free amino acids for malliard reactions when brought to a boil and alpha amylase when back in the mash tun.


Wheat beers aside, I do decoctions for bocks as well. Step mashing cannot achieve what a decoction mash can unless you step mash a portion of your mash to a boil, which is decoction mashing.


Most of my decoction mashes are a single decoction mash where I pull 2 gal of grain and 1.5 gal of grain/liquid/grist. I do not adjust this much, even for beers like a doppelbock that have a large grain bill over 18lbs (I brew 6 gal batches). For example on my standard hefeweizen, mash at 135f for 10 min then pull the decoction out, raise decoction mash temp to 155f (10min), hold at 155f for 10 min, then raise decoction mash temp to boil (10min), and remain at boil for 15 min. Stirring the decoction for 15 mikes isn't hard, if it is, well, HTFU. Then add decoction to main mash, which will mash at about 155f for another 25 min. Im looking at a 80 min mash including the single decoction. Ive done a couple double decoctions and they do add another 40-60 min, though I have found a single decoction will work for anything I brew.



Primitive - maybe, however the bottom line is the chemistry behind a decoction is complex and will take your brews to a new level. I can taste (and so can you) the difference between a step mashed hefeweizen and one that has been through a decoction, given all other parameters remain the same. On one test, I tried out Ayinger Celebrator Doppelbock Clone in a split 12 gal batch where 6 gal was multi step mashed (122f 20 min, 149f 30min, 158f 30min, mashout 170f 10min) and the other half was given a single decoction). Time in mash between a multi step and the decoction was the almost same, but the taste was vastly different. The decoction was complex, with the fig/farmstyle applesauce/toffee/chocolate just blowing away the tastebuds with a warm alcohol that just glides on by. The multi step mash was good, but seemed flat in comparison. Yeast, fermentation etc parameters were the same.

 

[GoeHaarden]

Another question...I currently have a hybrid RIMS tube setup. Ultimately, with decoctions you're just trying to get those malliard reactions out of boiling the grain? Right? The temp rise is simply killing two birds with one stone, but not the main goal nowadays?

With that said. Can I use my automated temperature stepping too? Let's say I dough-in at a protein rest temp and recirc like always to hold my steady temp. Immediately pull my decoction after doughing-in, and boil it causing those malliard reactions. If I reach the desired time at this step, my system will begin heating to the next step. At the same time, can I cool my decoction down to roughly the next step and add it back? Therefore, getting those malliard reactions, avoiding prolonged protein rest, and still maintaining good temp control.

 

[Yooper]

Another question...I currently have a hybrid RIMS tube setup. Ultimately, with decoctions you're just trying to get those malliard reactions out of boiling the grain? Right? The temp rise is simply killing two birds with one stone, but not the main goal nowadays?

With that said. Can I use my automated temperature stepping too? Let's say I dough-in at a protein rest temp and recirc like always to hold my steady temp. Immediately pull my decoction after doughing-in, and boil it causing those malliard reactions. If I reach the desired time at this step, my system will begin heating to the next step. At the same time, can I cool my decoction down to roughly the next step and add it back? Therefore, getting those malliard reactions, avoiding prolonged protein rest, and still maintaining good temp control.

Yes, that sounds ideal if I'm understanding what you're saying. Remember that you want to bring your decoction to the next rest temp and hold it there for conversion before bringing it to a boil before adding it back. That's what takes a while. If you can step mash via temperature with the rest of the mash, that sounds like it would great out great.

 

[GoeHaarden]

Yes, that sounds ideal if I'm understanding what you're saying. Remember that you want to bring your decoction to the next rest temp and hold it there for conversion before bringing it to a boil before adding it back. That's what takes a while. If you can step mash via temperature with the rest of the mash, that sounds like it would great out great.

Correct. Since, my main mash will step itself I don't have to really worry about it (too much anyways). Then just focus on the decoction and do:

mash at 135f for 10 min then pull the decoction out, raise decoction mash temp to 155f (10min), hold at 155f for 10 min, then raise decoction mash temp to boil (10min), and remain at boil for 15 min.

Then use this to achieve mashout

 

[BigEd]

Let's say you hit your temp with only using half or what you pulled for decoctions.

Unless you've made a large error in the calculations the chances of that happening are exceeding low. Having boiling and cold water on hand for quick temperature adjustments if you miss the target is a good idea. It's the boiling water you'll probably need.

If everything lines up correctly a decoction step will add 20F to the mash temp. I generally start @ 128F, go to 148F, then to 168F for mash out. The boiled fraction is added back to the main mash in its entirety.

If you have a smaller temperature gap between your final step and mash out you can adjust the quantity of the decoction pull, use an infusion or other heating method to achieve the right temperature.