Decoction method critique.

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Dave70

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I'm about to enter the exciting world of decoction mashing and was hoping a few wiser heads could run an eye over my method to confirm I'm on the right track.

The beer will be a Bock, mostly Munich with a little crystal, pale and choc.

To keep things simple, I'm starting with a double decoction.

Goes like this.


Mash in - 55 deg - protein rest 80 min.

Draw off 1/3 of the thick mash into pot, bring to boil, keep it going for about 15 min - yes, stirring.
Off boil.

*Add back to main mash - raise temp to 65 deg - sacc rest 60 min.

*If anyone has a nifty formula for calculating how much mash to pull in order to get the right numbers, I'd be glad to hear it. 1/3 seems like a good rule of thumb. If I hit 65 with a few scoops left in the pot, no biggie, I plan on just cool it and ad it back when it's right.

Pull another 1/3, boil for 15 min- add back to mash - raise to 75 deg for mash out for 15 min.

Carry on as usual.

Thats basically it. I can see evaporative loss being an issue, so the mash may need topping up before draining to the kettle.


Like I said, first time doing this so It;s more about getting a feel for the whole procedure than anything.

If I can produce a nice beer from it and not bottles of tannins or burnt toast, I'll be chuffed.
 
Sounds generally OK.

A couple of things though - why 55 for 80 minutes? Are you using well undermodified malt? A short rest for 5-10 minutes at that temp should be ample.

If your decoction is nice and thick and the pH of the mash is OK I can see no reason for tannin extraction and I have never experienced them in any of the beers I have decocted.

Although decoction originally broke down the starches in undermodified malt, I always like to rest mine at sacch temp for a short time before pushing up to the boil to ensure I'm not wasting grain. I tend to get the same or slightly higher extraction efficiency so something is working.

I would also boil longer to maximise melanoiden.

As for amounts, I am pretty casual with mine because I don't rely on the decoction for stepping. I add back and stir in slowly till either the next rest is hit (and then use the remainder in the next decoction) or add all in and step up with my immersion element. However, unless you find a better method, you could calculate the weight of the wet grain as a similar volume of 100 degree water and probably get pretty close. Have some boiling water on standby if you fall short.
 
I can't comment on the decoction process as I've never done one, but the crystal and choc malt looks a little out of place to me. Is there any particular reason you're using them? In terms of the crystal, I'd expect a decent flavour complexity from the combination of Munich malt, the decoction process and a long boil, and I'd use Carafa Special if anything to adjust the colour.

As manticle mentioned, the 80 minute rest at 55 seems like a long time to me too.

Cheers,
tallie
 
manticle said:
Sounds generally OK.

A couple of things though - why 55 for 80 minutes? Are you using well undermodified malt? A short rest for 5-10 minutes at that temp should be ample.

If your decoction is nice and thick and the pH of the mash is OK I can see no reason for tannin extraction and I have never experienced them in any of the beers I have decocted.

Although decoction originally broke down the starches in undermodified malt, I always like to rest mine at sacch temp for a short time before pushing up to the boil to ensure I'm not wasting grain. I tend to get the same or slightly higher extraction efficiency so something is working.

I would also boil longer to maximise melanoiden.

As for amounts, I am pretty casual with mine because I don't rely on the decoction for stepping. I add back and stir in slowly till either the next rest is hit (and then use the remainder in the next decoction) or add all in and step up with my immersion element. However, unless you find a better method, you could calculate the weight of the wet grain as a similar volume of 100 degree water and probably get pretty close. Have some boiling water on standby if you fall short.
To build the suspense...
No, really these are just ideas I've cobbled together from a bunch of different sources - mostly this one.

http://braukaiser.com/wiki/index.php?title=Decoction_Mashing

This is precisely why I'm throwing it out there. 10 minutes sounds far more agreeable to me.
How long would recomend for the boil?


tallie said:
I can't comment on the decoction process as I've never done one, but the crystal and choc malt looks a little out of place to me. Is there any particular reason you're using them? In terms of the crystal, I'd expect a decent flavour complexity from the combination of Munich malt, the decoction process and a long boil, and I'd use Carafa Special if anything to adjust the colour.

As manticle mentioned, the 80 minute rest at 55 seems like a long time to me too.

Cheers,
tallie
Havent decided on the final recipe yet. I plan on having a good read of the Bock chapter in Designing great beers tonite. I'm hoping to get some colour and flavour from the Maillard reaction, to that end I may end up just going 100% Munich with some Hallertauer or Saaz up to about 27 IBU and WY 2308.
 
Dave70 said:
Havent decided on the final recipe yet. I plan on having a good read of the Bock chapter in Designing great beers tonite. I'm hoping to get some colour and flavour from the Maillard reaction, to that end I may end up just going 100% Munich with some Hallertauer or Saaz up to about 27 IBU and WY 2308.
Yes, even if you're brewing to style, I think you'll get enough colour formation from a combination of a high % of Munich, the decoctions and a long boil.

If you're interested, I've just updated the Doppelbock thread with details of my recipe that was entered as a Traditional Bock and placed first in the Strong Lager category at last year's AABC. Again, it's not decocted, so keep that in mind.

Cheers,
tallie

Edit: get rid of unused quoted text
 
100% base malt with an extended boil (2-3 hours) does wonders for colour and flavour development so you can reduce/remove spec malts if you look at doing this.

If you mean though (and I think you do) how long should you boil the decoction for then go for at least 30-40, especially for the first, thicker one.
 
55C for 5 mins rather than 80 mins as originally stated.

Beersmith calculates decoction volumes for you although it is a bit wonky. I use a kitchen sieve to strain out the liquid - you want only enough liquid to stop the grain from sticking and burning.

Like Manticle, I like to rest the decoction prior to boiling so for me it is 15-20 mins at 65C, another 10-15 mins at 70C and then boil for 20 mins (minimum).

Put back into tun and stir. Wait 45 mins at 65C and then draw out the next decoction. Repeat above.

I decoct pilsners, dunkels as a standard, never made a bock so won't comment on your recipe.
 
Using the thin mash to sparge out? Well there you go. Would have come in handy a few times when I've maxed out the esky.

The Kaiser also has a fine trio of vids. A bit more in depth.

http://youtu.be/_V1zt0mW084
 
The tirck to decoctions is to pull more than your mathematically need and then add only back that which raises the temperature to your next rest temperature.

The stuff left sitting in the decoction pot cools down rapidly - just add your thermomenter to it and return it back to the main mash when it's the same temperature.

Alternatively, leave it in the decoction pot and add the next decoction to it.

End of the day, the only point of decoctions on a homebrew scale (besides being something every one needs to tick off in their skillset) is to generate some flavour and colour - modern malts are well malted, we have thermometers and we don't need to increase efficiencies for profits.

Decocting is like restoring a 1932 Ford; fun, but for 20K you can get to B from A with a whole lot less hassle in a Falcon.
 
You don't need to use adjuncts with modern malts either, but some brewers do. You don't need to rack your beer to a secondary fermentor, but some brewers do. Some people would also prefer to drive the 32 ford around than a plastic, computerised, character devoid device on wheels.
 
mje1980 said:
You don't need to use adjuncts with modern malts either, but some brewers do. You don't need to rack your beer to a secondary fermentor, but some brewers do. Some people would also prefer to drive the 32 ford around than a plastic, computerised, character devoid device on wheels.
You decoct how many brews on average?
 
Nick JD said:
The tirck to decoctions is to pull more than your mathematically need and then add only back that which raises the temperature to your next rest temperature.

The stuff left sitting in the decoction pot cools down rapidly - just add your thermomenter to it and return it back to the main mash when it's the same temperature.

Alternatively, leave it in the decoction pot and add the next decoction to it.

End of the day, the only point of decoctions on a homebrew scale (besides being something every one needs to tick off in their skillset) is to generate some flavour and colour - modern malts are well malted, we have thermometers and we don't need to increase efficiencies for profits.

Decocting is like restoring a 1932 Ford; fun, but for 20K you can get to B from A with a whole lot less hassle in a Falcon.
Come on, thats just the miserable, pragmatic cat talking.
If we start applying those kind of reductions to the HB game, we might as well sell our pots and all start using fresh wort kits.
Whilst practices like 'racking to the secondary' may be a debatable endeavour in terms of adding anyting to a hopped out APA, based on the opinions of folk who constantly use the decoctions, I believe it has something to offer.
If only flavour and colour, though it seems to be more than that, thats good enough.

I can still rembember a time when when I was a mere 'lurker' at AHB looking at the all grain section thinking 'why the **** would you bother with that bullshit, this can of Coopers I got from Wollies makes awesome beer'.
 

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