22 replies to this topic

[Jimmy James]

I am going to brew a Bohemian Pils in a couple weeks time and am going to do some kind of decoction and need some help understanding the benefits of double or triple decoctions. In some commercial pils such as Staropramen there is a noticeable deep-golden hue and malty character that I would guess originated from a decoction but could now be due to specialty malts? At any rate, I am doing the decoction more just to do it with this style and see how the end result turns out. On to my question:What difference would I expect in the beer between these processes:1. Dough in for acid rest, 3 x decoct for protein, sacch and mash-out2. Dough in at protein rest (130) and decoct 2X for sacch and mash-out3. Dough in at protein rest (130) and step up to sacch rest, then decoct for mash-outAssuming I can get the water right, am I right in thinking the acid-rest is not critical? I am leaning towards the third option, single decoction to mash-out, but I can do any of the 3. I just would like to hear some thoughts from those who've done decoctions as to whether the additional steps improve the beer. Thanks for your help. I plan to do this for a Kolsch also, so I might try a couple of these processes out depending on the feedback.

[Big Nake]

I have only done a single. What I learned was that it helps to get your original temp to about 130° or so and then take a good amount of the thick mash for the decoction so you can get enough heat to raise the main mash back into your 150° range. So I think I started with the entire mash at about 130°, I took approximately 40% of the mash and brought that to 150-152° for 20-30 minutes, then brought it to a boil and stirred constantly for 30 minutes, then added that back to the main mash where I only ended up at about 146° or so. I do not have any way to direct-fire my mash so I left it. Some of the other locals told me that it would've been good at that point to just dump the entire mash back into my brewpot, fire it up on my propane burner, get it back to 152° and then drop it back into my MT for the next 60. Lots of extra work and I need to refine the process for sure. Can't comment on the 2x or 3x. Good luck.Ps. You know that there are 2 schools here... the Decoction Underground that suggests that decoction is the only way and then The Others who suggest you can do the same thing with a boatload of Munich and/or Vienna and slightly higher mash temps.

[Jimmy James]

Thanks Ken. Good to hear you came so close to hitting your numbers the first time!Did you notice any different character in the beer? Just curious. I hear you on the two schools of thought. I myself figure the only way to know for sure is to do it. That, and what the heck - gotta keep brew day interesting somehow.

[denny]

First, do you need an acid rest and protein rest? An acid rest depends on your water and a protein rest depends on the grain you use. Second, the results of an experiment I did lead me to believe that a single decoction will not make a noticeable difference in the beer. You can see the results here, starting on pg. 25...https://www.beertown...s/DennyConn.pdf

[Jimmy James]

Thanks for the link Denny. I read through the decoction experiment and find it interesting and need to read it again and think about it a little. This is exactly the type of experience that makes me wonder if a double or triple decoction is necessary. Since one of the beers in your panel was double-decocted while the others were all single decoctions it would be great to see the data for that one and if the panel perceived it differently than the others. At any rate, the take-home doesn't change and I am looking forward to my own decoction experiments!

[denny]

I'd encourage anyone who's interested in it to try one and decide for themselves. But it's important, if you want to make an accurate decision, to do a blind tasting. It's too easy to do a decocted beer and say "WOW, this realy made a great beer!" if you know in advance it was decocted.

[Lagerdemain]

I've done two triple decoction mashes side by side with single infusion mashes (using identical grain bills, hops, yeast, ferm temps, etc, and fermenting side by side in the same fermentation chamber). I realize that my sample size is far too small and the circumstances vastly too uncontrolled to qualify as an experiment, but my results were quite in line with what Denny has reported.First, I did a Czech pils. I slightly preferred the flavor of the infused version; my wife couldn't tell the difference. Next, I did an Oktoberfest. Neither I nor my wife could tell any appreciable difference between the two beers. I concluded that for the beers that I make, with the grains that I use, that I couldn't justify the extra time and effort required to perform a triple decoction mash. Can others' results vary? Of course. And no one wants to do a time-consuming decoction mash only to learn that it was all a waste of time and energy, so naturally that can skew reported results.

[Big Nake]

I love this discussion. I will link to a conversation we had on our local board which started with an Altbier recipe I was looking at. It ended up being a 4-page decoction discussion with Ted and BryanH (both formerly of the GB and other forums...) and a good discussion for the new decoction brewer. There's also another one here. Cheers.

[VolFan]

I've done a triple decoction twice. My friend and I both came to the conclusion that the beers did have a slightly more maltier backbone than the single infusion we compared it to. However, I also came to the conclusion it wasn't worth the extra effort.I'd say go ahead with your plans and try it if nothing else to see what the process is like and to say you have done it. Be prepared to keep those grains stirred to prevent scorching.

[Jimmy James]

Thanks for posting the links Ken, and everyone else for the comments and experiences. I agree wholly with the comments about bias in tasting, blind tasting and such. Based on the comments here I think I'll do a full triple decoction including an acid rest as having the correct mash pH seems critical. If the triple decoction doesn't do the trick then I guess nothing will. I like the idea of brewing single-infused and decoction batches and having a blind tasting, maybe I will be able to find some volunteers around the San Diego area

[dapittboss]

What? No "beguiling maltiness" from a decoction? That's heresy!

[Lagerdemain]

Thanks for posting the links Ken, and everyone else for the comments and experiences. I agree wholly with the comments about bias in tasting, blind tasting and such. Based on the comments here I think I'll do a full triple decoction including an acid rest as having the correct mash pH seems critical. If the triple decoction doesn't do the trick then I guess nothing will. I like the idea of brewing single-infused and decoction batches and having a blind tasting, maybe I will be able to find some volunteers around the San Diego area

One thing that can throw off your results (or, put another way, create artificial differences in results) is that the typical decoction schedule calls for different (higher) saccharification rest temperatures (frequently around 158-160 degrees) than the normal saccharification rest temps of an infusion mash (around 148-152 degrees, give or take). I corrected the saccharification rest temps of my decocted beers so that they were the same as the infused batches, but I am unsure whether others made this correction or not.

[Jimmy James]

I noticed this too. I am thinking of going higher in the sacch rest. My understanding is the decoction process has already created an allegedly more fermentable wort so you can go higher on the sacch temp. At least that's my limited understanding from reading up on it so far. Thanks for pointing this out.

One thing that can throw off your results (or, put another way, create artificial differences in results) is that the typical decoction schedule calls for different (higher) saccharification rest temperatures (frequently around 158-160 degrees) than the normal saccharification rest temps of an infusion mash (around 148-152 degrees, give or take). I corrected the saccharification rest temps of my decocted beers so that they were the same as the infused batches, but I am unsure whether others made this correction or not.

[Big Nake]

One thing that can throw off your results (or, put another way, create artificial differences in results) is that the typical decoction schedule calls for different (higher) saccharification rest temperatures (frequently around 158-160 degrees) than the normal saccharification rest temps of an infusion mash (around 148-152 degrees, give or take). I corrected the saccharification rest temps of my decocted beers so that they were the same as the infused batches, but I am unsure whether others made this correction or not.

I noticed that too. Why are the saccharification rests always shown higher (156-160°) on a decoction? On the single-decoction I did, I was only able to get my main mash temp up to 146° after adding the decoction portion back to the mash. I should also say that I made the mistake of making a beer that I was not familiar with... I should have made my normal Oktoberfest Lager so I could compare it.

[MetlGuy]

I have done a couple out of necessity before I upgraded my mash tun. I fellow brewer has switched to deconcoctions for his Alt's. I believe the deconcoction change has made his beer taste more authentic. I brought back several exemplars from Düsseldorf last spring and we had a side by side. They were much maltier with.My $0.02

[trimpy]

Decoction had a couple of historic uses. I helps when the malt has an inconsistent level of modification (not really a big deal these days unless you are home malting) and you could brew w/o a thermometer and achieve a decent level of accuracy. The idea was that you could detect something that was around your own body temperature, and by pulling measurable amounts and heating to a known temp (boiling) you could raise the temp of the main part of the mash predictably.I wasn't able to really tell the difference, but then again I didn't do a side by side comparison. I am going to try it again one my latest batch of malt is ready and see if it helps with my poor extraction when compared to earlier trials.

[rockon]

I thik it would be interesting for a homebrew club to get maybe 10 - 20 people to all brew the same recipe. Some would do a decoction and some wouldn't. Then, have a gathering to taste and rank the beers. Nobody would know which ones were done with a decoction and which ones weren't until the end. Then, see if the rankings show a clear preference for one type or another.

[japh]

Decoction had a couple of historic uses. I helps when the malt has an inconsistent level of modification (not really a big deal these days unless you are home malting) and you could brew w/o a thermometer and achieve a decent level of accuracy. The idea was that you could detect something that was around your own body temperature, and by pulling measurable amounts and heating to a known temp (boiling) you could raise the temp of the main part of the mash predictably.

Now that's an interesting observation - that it could have originally been a way to get consistent results without a thermometer.Anyone do a largeish sample size with two side-by-side batches? Maybe with a homebrew club?

[denny]

I thik it would be interesting for a homebrew club to get maybe 10 - 20 people to all brew the same recipe. Some would do a decoction and some wouldn't. Then, have a gathering to taste and rank the beers. Nobody would know which ones were done with a decoction and which ones weren't until the end. Then, see if the rankings show a clear preference for one type or another.

That's pretty much what my experiment was about, except that it involved brewers from around the world.

[rockon]

That's pretty much what my experiment was about, except that it involved brewers from around the world.

I guess I should have clicked on your link first. I'm reading the results now -- Good Stuff!!