Decoction Mashing

[SJW]

I have been looking into decoction mashing as I brew mainly German Lagers. As there are no Wiki topics on this I would like to start a comprehensive discussion.
I found this on You Tube, and was interested in what people think.

As we use good quality malts and this is not necessarily a required mashing method a few question spring to mind, like, does it do the mash any harm leaving the original mash at 45 deg C or 52 deg C, what ever your mash in temp is, while you pull off and decoct your first decoction?
The process as I understand it is:

* Mash in for an acid or protein rest.
* Pull out 1/3 of the thick mash and raise to 65-70 deg C SLOWLY and let that site for 20mins for full conversion,
* Then boil for 10 -15 mins
* Then slowly add bit by bit back to the mash to raise to say 67 deg C
*If theres any decoction left let it cool to 67 deg C then add to main mash.
* After full conversion say another 30min draw off liquid and boil
* Add back to mash to raise temp to 76 deg C to complete conversion.

It would make for a very long brew day but it should be worth it.
Any comments and experiences would be very welcome.

Steve

 

[warrenlw63]

Hey Steve

If you're really going to take a leap into decoction mashing Gregory Noonan's "New Brewing Lager Beer" is a great guide to the whole process from the ground up.

Be warned though you'll probably regret attempting it around half way through the mash. <_<

To me the benefits don't really equate to the extra effort.

Warren -

 

[SJW]

Thanks Wazza, I bet Tony will have something to say on the matter.

 

[newguy]

I've done quite few decoctions. Yes, pull ~1/3 of the thickest part of the mash, but don't heat it slowly. Put it on the stove, stir like hell, and get it up to sacch temp as quickly as you can. Let it rest there for 5-10 minutes, then heat to boiling. Stir like hell again. You can stop once it starts to boil as there is enough movement to minimise scorching. Dump the whole works back into the mash - don't hold any back. If you overshoot, just add cold water. I can say from experience that overshooting your target temp is rare; undershooting is much more likely. If this happens, just boil 1 or 2 litres and dump that in. Once your mash temp settles, pull the next decoction. The main mash will sit at the desired temp while you are heating up the decoction. The times work out much better this way.

Things I've learned:
- triple decoctions are not really worth the effort as you can get the same flavour from a double (protein rest -> sacch rest -> mashout)
- a single decoction (sacch -> mashout) gives almost the same flavour as a double
- don't sweat missed target temperatures; the beer will still turn out right

The more decoctions you do, the better your feel for the proper volume to pull will get. Use the liquid volume for calculating your pulls; if you use 15l of water to mash in, pull about 5-5.5l of mash; don't worry about the water/grain composite volume. The more you do, the quicker you'll get as well. My first triple decoction extended my normal 6 hour brew day to 13 hours. It was frustrating too. In a few tries I managed to be able to do a double decoction and it would extend my brew day by only 1 hour over the non-decoction mash.

 

[Tony]

Thanks Wazza, I bet Tony will have something to say on the matter.

you missed the <_< at the end of that mate.

 

[SJW]

Well I was just going to PM u Tony but I thought this would be a good chance to share your knowledge of this mashing technique with us all. I brewed and Oktoberfest yeasterday, double infusion style, and missed the 67 deg C step, so I pulled a small decoction and boiled it to bring the main mash up to temp. It was pretty easy and although we use Weyermann Malts in our German Lagers that do not really require this method I thought I should give it a go.

Steve

 

[matti]

Well I was just going to PM u Tony but I thought this would be a good chance to share your knowledge of this mashing technique with us all. I brewed and Oktoberfest yeasterday, double infusion style, and missed the 67 deg C step, so I pulled a small decoction and boiled it to bring the main mash up to temp. It was pretty easy and although we use Weyermann Malts in our German Lagers that do not really require this method I thought I should give it a go.

Steve

Well done.
Its is good for a couple of things but as you said, its is not entire necessary with fully modified malts.
You might recall a thread called something like. "A technical discussion of the benefits step mashing".

It will be in the the AG thread somewhere.

Decoction to me, helps raise the temperature, add colour and get some of the melanoidans out.
It will give the Lagers and Pilsners a maltier profile.

 

[Tony]

sorry mate......... just thought it was a "oh here we go with tonys 2 bobs worth again" thing

but i was wrong......... sorry.

I have got my cammera out the last 2 decoction mashes i have done to take progressive pics and do a wiki article on it but always forget to take the pics.

Next time i will.

The beer i am drinking ATM is an Altbier, double decoction mashed and its very malty. more so than if it was single infusion mashed. Also the Maibock that i decoction mashed fopr the mash paddle and hunter case swap (and now wont be entering either due to a lacto bacteria infection making it slightly sour) also has a deep maltiness.

I think decoction mashing gives a maltiness thats more prominent without being cloying or sweet.

A decoction wont make your beer 10x better. It gives it more malt depth and also improves efficiency. It improves colour depth. I have also found that it reduced break in the kettle as some is in the mash from boiling the malt. This can hamper sparging so be prepared for a stickier mash or use some rice gulls to help out.

I usually mash in at 52 deg and pull the amount determined from Promash and slowly raise it to 66 deg. Let it sit for 20 min and then slowly raise it to boiling. I let it simmer with a lid on the pot for 20 min then pour it back in the origional mash and stir to mix it all in. You will see the colour development and the smell of boiling malt (especially lots of munich) is fantastic.

I rest it at a slightly lower tamp that i normaly would for an infusion mash, usually 2 deg less. I have found that raising the decoctions up through the temperature range creates enough hi end sugars for body and if you mash it hot at 67 you will get very poor atenuation. I mash at 65 and let the decoctions add the body.

Back to the rest............ rest for 30 min and pull either a thick grain decoction or a thin wort decoction (i usually do a non traditional think grain one) and bring it slowly to the boil. if thick grain, boil for 20 min andd add back for a 70 something mash out or if thin wort, add back in as soon as it boils.

mash out and sparge as normal.

It will add an extra hour or 2 to your brew day but the smells are great. I only do it for beers that really call for a bigger malt profile like bocks, altbier, pilsner, and works well for a wheat too.

Just a quick note............. the English old ale i wone the state comp with........... i decoction mashed it after i missed the mash temp by 8 deg. The malt profile is what did the job!.

cheers

PS........ will do a wiki next time i decoction mash which wont be long if i have another shot at the paddle.

 

[SJW]

Thanks Tony, thats the type of info I was after. I guess all thats left is to give it a go.
WOW, I am now using liquid yeast and by doing decoctions I might make a real brewer yet.

Steve

 

[warrenlw63]

Hey chaps

Wasn't necessarily slagging the virtues of decoction mashing. Having done a few I just don't see the extra benefits being worth the extra stuffing around. Sometimes if things don't work they can make for a very messy and protracted brew day. That being said why not do a couple just to find out for yourself.

Only beer which I can see any really benefit being derived from is a Hefeweizen.

To me Steve if you're really going to notice and "real" benefits I'd suggest doing the exact same recipe twice (one infusion and one decoction) and comparing the beers side by side. Its really the only real way of knowing.

Personally I reckon melanoidin malt and step mashing is far easier. B)

Warren -

 

[SJW]

Personally I reckon melanoidin malt and step mashing is far easier.

Warren -

I suspect yoy are 100% correct. I will give it a go on a Dortmunder and mayber a 100% Weymanns Premium Pils that are coming up. I think I will do very similar to Tony. Mash in for protein rest and decoctions for the 67 and 76 steps. Should not add much to the brew day.

Steve

 

[Tony]

I suspect yoy are 100% correct. I will give it a go on a Dortmunder and mayber a 100% Weymanns Premium Pils that are coming up. I think I will do very similar to Tony. Mash in for protein rest and decoctions for the 67 and 76 steps. Should not add much to the brew day.

Steve

Drop that 67 a couple of deg mate............ all that heating of the pulled mash through the temperature range will produce all the high order sugars you want. Unless you like your beer finishing at 1.020.

I also mash in at about 2.5l/kg.

When you boil the decoction it has to be "thick mash" with only just enough liquid to keep it moving. Its the liquid in the mash that holds all the enzymes once youve mixed it all in so boiling lots of liquid up front is not so good. You need to keep it gently stired while heating to stop it scorching but i have found once its at boiling, the smallest of flames will keep it simmering with no burning (even in my thin cheap pot) with the lid on the pot.

If an infusion mash and some melanoiden worked the same............ why do all the great beers from germany and the chech republic get decoction mashed.

I would of thought if there was no benifit, the bean counters would squash it?

Going to have a go at a Pils Erquelle soon with Bohemien pils and a tripple decoction. 35, 52, 65, 76. Will be a long day but i cant wait. I love the smell of boiling up the malt.

Going to use lots of Saaz in the boil and try and get thet hoppiness from the big up front 40 min bitterness addition. perhaps a touch at the end but i want that deep saturated hoppiness this beer is suposed to have, not the confronting late hop hit that fades quickly.

Will get the camera out!

cheers

 

[Weizguy]

Recently made a ridiculous 1.089 s.g. Helles weizen by triple decoction.

Have also made a Czech pils by triple decoction.

My first bucket all-grain was a decocted Oktoberfest

Any style that benefits from maltiness and a bit of extra body can be done with a decoction.

Tony, don't you trap DMS in the wort by boiling with the lid on, even at that early stage?
I thought I read about it somewhere. B)

 

[Online Brewing Supplies]

Recently made a ridiculous 1.089 s.g. Helles weizen by triple decoction.

Have also made a Czech pils by triple decoction.

My first bucket all-grain was a decocted Oktoberfest

Any style that benefits from maltiness and a bit of extra body can be done with a decoction.

Tony, don't you trap DMS in the wort by boiling with the lid on, even at that early stage?
I thought I read about it somewhere. B)

You do need to leave the lid off for a while to get rid of nasty volatiles but most DMS is formed by prolonged cooling of your wort.Simple terms: Finishedwort is too hot for too long.Quick cooling or nitrogen blanket will fix DMS.

 

[Tony]

YEah its heated and brought to the boil with the lid off but when it does its first mash rest and when i boil it i leave the lid on.
I find that boiling with the lid on meeds almost no flame at all and doesnt scortch the mash. Lid off i have to turn up the heat and it burns on the bottom which is worse in my book.

cheers

 

[SJW]

Sounds good fellas. I might need to replace my HP reg for the BBQ one as the HP reg will throw too much flame I think.
Will give the Dormunder a Double decoction 65 and 76 after mashing in at 52, and if all goes well will go the tripple on a Czech Pils.

Steve

 

[drsmurto]

Been thinking about doing my first decoction for the Bo Pils i am planning for my sick day *cough* on Thursday. I have wyeast 2000 on the stir plate in anticipation and have been reading everything i can find for the last week and a bit.

I think i have it sorted out in my head but i do have a few more questions.

Can i use the NASA for the decoction steps. ie. pull the decoction, put it into my stockpot and use the NASA to heat it or is it to powerful and likely to scorch the malt? From memory Urquell is 35, 53, 62, 73 - how big a step can we make between steps using a decoction? Is 62 to low a sacc rest? Given what Tony said about the decoctions resting at 67 this seems to be OK?

Cheers
DrSmurto

 

[matti]

Can i use the NASA for the decoction steps. ie. pull the decoction, put it into my stockpot and use the NASA to heat it or is it to powerful and likely to scorch the malt? From memory Urquell is 35, 53, 62, 73 - how big a step can we make between steps using a decoction? Is 62 to low a sacc rest? Given what Tony said about the decoctions resting at 67 this seems to be OK?

Cheers
DrSmurto

What grain bill are you using?

I have been toying with the idea of decoction mash on my Rambo burner.
My Agendum is: to raise the temp for double batches in 36 Litre cooler as i will run out of space for stepmashing introducing
more hot liquor for all the steps.

The trouble i can foresee is the how is one to hold the rest temp of the decoction mash for 10 minutes or so at 72 degrees with so much heat applied.

If you are going to use your nasa-burner it would be a good idea to dilute the decoction somewhat stir like crazy and quickly return "it" to the main mash.
Please report back.

Matti

 

[drsmurto]

100% weyermann pilsner malt, bittered with Perle and late additions with Saaz.

 

[Dr Gonzo]

Mark,

I was planning on knocking off early one night this week and doing another pils.
Would you like to see a decoction mash first hand before you take the plunge?