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Old 08-11-2006, 03:09 PM   #11
Willie3's Avatar
Jun 2006
Hackettstown, New Jersey
Posts: 765
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Originally Posted by Baron von BeeGee
Here's a pretty good link which details the process fairly well IMO:


He recommends pulling 33%, I believe, but I usually pull a little more for a safety margin. Also, for a HW, I wouldn't boil longer than 10-15 minutes for fear of darkening the wort too much. For a darker beer you can boil 30-45 minutes. Finally, I can't remember if he recommends stopping at 150-155F for a short saccharification rest in the decoction pot, but I've been doing it as it's mentioned in all the literature I've read on how German breweries do their decoctions.

That is a great website! Thanks. I have but two questions for you experts.

1.) I am going to brew an AG of a traditional Beglian Dubbel with traditional grains and 2 row briess as a base ~ 5lbs. I would like to do a tripple decoction mash. Do BDs usually have this characteristic? Total grain bill is appx 10-12 lbs. Nearly 1/2 are specialty grains with ~1lb wheat for head retention.

2.) I am going to do an acid rest, a protien rest, a saccharification rest, and mash out. When I mash out how long do I rest before sparging?

- WW

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Old 08-11-2006, 03:25 PM   #12
Dec 2005
Glasgow, Scotland
Posts: 696
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Triple decoction, you're a brave one. Here's another oft-quoted FAQ from rec.crafts.brewing, (hope no-one minds the massive post):

A Micro-FAQ
by Marc de Jonge (dejo...@geof.ruu.nl)
Every now and then questions on decoction mashing come up in the Homebrew
Digest, for that reason I've put together this small FAQ file. I hope this
is enough to get you started. If you have any comments or questions on the
contents feel free to mail me at the above address.


What is decoction mashing?
In essence decoction mashing is a temperature controlled mashing method that
differs from the normal 'step-infusion' mash only in the way the heat is
The difference is that in decoction mashing part of the mash is boiled in a
separate kettle. The boiled part is added back to the mash to achieve the
required temperature rise. The effect of the boil on the final beer is very
strong. In my opinion decoction mashing is important (together with the
choice of malt and yeast of course) for achieving the characteristic malty
taste found in many of the best commercial beers.

What beers are made with decoction mashing?
The decoction method is the preferred mash method for many beer styles
originating on the European continent. For example:
Pilsner and pilsner imitations (From Pilsner Urquell to Bud)
Almost all german beers (maerzen, bock, weizen, some alts, rye, dortmunder)
Some of the lighter Belgian ales (De Koninck, Palm, Rodenbach)

Advantages of decoction mashing
Because of the boiling, cell walls of the grains are destroyed. This allows
an easier access for the enzymes to the starch. As a result the efficiency
of decoction mashes is generally higher than for other methods. (This is
probably the reason almost all megabrewers use this method)
Grains that need gelatinizing at high temperatures can be boiled separately
in one of the decoction steps (can be useful if you use for example rice or
The following advantages are in my opinion more important for homebrewers:
Boiling part of the mash extracts more flavour from the grains. Especially
beers made with a lot of pale malts improve by this effect.
A slight Caramelization can occur during the boil, giving a fuller flavour
to the beer (I don't know why, but the effect of adding dark malt is not
quite the same).
Part of the protein already coagulates during mashing, which helps to
produce a clearer beer.
The method allows stepped-temperature mashing in a tun that cannot be heated
(picnic cooler, or 6 yards high wooden barrel)


The traditional decoction methods are designed for very poor quality malts,
as a result they often require very long mash times. (Note that for amateur
brewers this is not an issue because it is almost impossible to get these
poor malts.)
Splashing the hot mash may cause some additional HSA.
Care must be taken to avoid scorching the mash when it is boiled, this means
the decoction method requires more attention and work (stir when you heat).
pH must be checked and corrected to avoid extraction of tannins from the
husks (anything below appr. 5.7 is ok)
Special care must be taken for mash-out (which is of course optional
anyway): boiling the grains the last time may release some more starch that
will not be converted because you've just wiped out the enzymes. The
traditional work-around is: boil only the clear liquid for mash-out.


Some general considerations
First, a table with some temperatures for the unmetriculous:
35C = 95F, glucanase rest (breaks down gummy stuff)
52C = 127F, Protein rest.
63C = 145F, Beta amylase rest for dry beers (pils).
. (anywhere between these temps is ok)
67C = 153F, Beta amylase rest for thick beers (bock).
72C = 158F, Alpha amylase rest for dry beers (pils).
. (anywhere between is ok)
75C = 167F, Alpha amylase rest for thick beers (bock).
78+C = 172+F, mash out range.

Strike temperature:
The examples that follow give an indication for the strike temperature,
getting this right is often more art than science. In practice (when you use
2.5L/kg or 1.3qt/lb) you add the water at a temperature of 7C or 12F higher
than the mentioned value, just like you would for an infusion method.
Calculation of boiling volume:
In the following examples I've indicated what proportions of the mash should
be boiled (roughly 1/4 to 1/3). When taking out this fraction, you could try
leave behind as much clear wort as possible. However, the risk of scorching
increases if you are to zealous. My preferred method: stir well and scoop
out the right amount without worrying. This does not go for mashing out,
when you only take the clear liquid off the top.
An approximate formula for calculating the boiling fraction F is the

F= --------

TB is the temperature of boiling mash (near 100C/212F)
T0 is the starting temp
T1 is the required temp. (Units F or C, don't mix them).
X depends on your mash setup, but 10C or 18F is a typical value, you can
adjust this if you find you need to boil a lot more or less to hit the right

Some practical examples
Obviously decoction mashing methods can vary as much as anything in brewing,
but here are some practical examples. I've used the first three myself, the
last is a traditional example.
Short 1-step method
For simple pilsners, koelsch, alt and even pale ales that require a bit more
malt flavour.
This method takes approximately two hours.

Preferably use a good 2-row malt, not too many starchy adjuncts

Strike temperature 64C, stir well and rest for 20'.
Stir and immediately put 1/3 of the mash in a pan (the remainder stays at
64C). Slowly heat the pan to 73C, rest for 20'.
Bring to boil and maintain a good rolling boil for 15-30', beware of
Add boiling mash back to the rest, stirring well until temperature is around
72C. (Normally you won't need everything you've boiled, add the remainder
when it has cooled down a little). You can add dark malts at this time too,
if you want to keep the dextrin level high.
Rest until saccharification is complete (probably between 30' and an hour,
test the clear wort for starch residue).
No mash-out, start sparge immediately.
Average 2-step method
For Belgian pale ale, German pilsner, Munich styles and Bavarian wheat beer.
This method takes 2.5 to 3.5 hours, depending on the grist.

Strike temperature of 53C, stir well and rest for 20'
Stir and take 1/3 of the mash. (If you use a large proportion of unmalted
grains you can take less of the mash and add water and dry crushed grains to
make up 1/3 of the total volume). Heat to 72C, rest for 20' (malt) to 40'
Bring to boil and boil for 15-30'
Add back to reach a temperature of 65-67C, rest 15-35'
Take 1/4 of the mash, boil for 15-30'
Add back to reach a temperature of 70-73C, rest until saccharification is
complete (30'-1h).
No mash-out, start sparge immediately.
3-step method
for extremely poor quality malt and strange adjuncts. This method can take 3
to 6 hours.
(In this example the grist is 45% pilsner malt, 35% buckwheat and 20%
unmalted wheat, should I deposit the name buckwhiter?)

Strike water malt and wheat for temperature 53C, rest for 40'
Boil a 'porridge' of buckwheat and water during this rest.
Add this to the mash, for a temperature of 63C (I wanted a dryish beer), and
rest for 35'.
Heat 1/3 to 72C, rest 30' and boil 25'.
Add to mash for a temperature of 70-72C, rest 50'.
Take clear liquid off the top, bring to boil and add back for mash-out (5').
Start sparge.
3-step traditional
(Commercial example from De Clerck, Leerboek der brouwerij, Leuven, 1962),
this one takes 5 to 6 hours. It is more or less the method used for Pilsner
Strike for 35C, rest 20'.
slowly (20') heat 1/3 to 65C, rest up to 25'.
slowly bring to boil, boil up to 25'.
Add back, T=52C, rest 5'.
slowly heat 1/3 to boiling, boil up to 25'.
Add back, T=65C, rest up to 50'.
slowly heat 1/3 to boiling, boil 5'.
Add back for mashout (77C).

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Old 08-11-2006, 04:36 PM   #13
Exo's Avatar
Jul 2006
Posts: 768
Liked 8 Times on 7 Posts

Hey, thats great. Thanks for the cut/paste. That should be a sticky!
Wasp Bitten IPA (a Walker-San clone);Cheesefood's Caramel Creme; Wee Heavy Scottish Ale;
Flyin' Hornet Pale Ale(Mirror Pond clone);Oktoberfest Ale
Boom-Boom Apricot Hefeweisen; Forbidden Ale;Pale-Ass Ale (SNPA Clone); Ol' Man Winter Ale
Dead Guy clone
Walker's Espresso Stout; BrewPastor's Bastard Lager
But honey, how else am I going to get enough bottles for my next batch? *burp*...*fart*

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