decoction mashing

So my first attempt at a Belgian Wit was this Sunday and it went ok.. the process called for a protein rest since the mash was nearly 50% wheat.. I hit the protein rest dead on at 125F and then made it into the 140's for the second rest but didn't have enough space left to get the thing to the 158 mark so it set at about 148F for a bit while I drained some wort off and brought it to a boil and added it back in.. I *thought* that was a decoction mash..stupid me. I can't see that I did any harm by not scooping the grains off with the wort but I did get to thinking about it..
How can you boil the grains and wort for your decoction and not end up extracting tannins? I thought tannin extraction was probable anytime your grains sat in water hotter than 175F... So, what is the proper technique for a decoction - how thick should it be? And why don't you end up with an astringent beer as a result?

Read here: http://www.strandbrewers.org/techinfo/decoct1.htm

We've all been taught that when begining I suppose becuase whoever was teaching didn't think we'd understand ph's role in tannin extraction. The fact is that it's ph, not temperature that is most important in preventing astringency from mashing.

That's one heck of a fine link. It finally explains why you want to boil the grain, but not the wort! I've been using 5.2 to control pH for the last year and it completely eliminated tannin problems in my dark ales. Which is a nice bonus, since I was adding the 5.2 to improve efficiency with the very soft water I have here.

Funny, I boiled exactly what I wasn't supposed to boil. Oh well, lesson learned. Funny thing is, I still had decent efficiency - 1.052 OG which was right on target for the receipe. I'm definately gonna try a decoction mash next time.

mmmmm... blue moon here I come!

that's a nice club web page........

The Strand Brewers Club in my neighborhood too. Maybe I should think about attending some meetings...

dude,i would! no telling what you could pick up from those guy's? probably a great resource of recipes, equipment ideas, etc.

Brewsmith said:

The Strand Brewers Club in my neighborhood too. Maybe I should think about attending some meetings...

Click to expand...

hEY, I was wondering if there is a calculation or formula for decoction mashing.
There is a kit from NorthernBrewer for a dunkelweizen (I asked you a question about that typy of ale earlier) Well the kit they sell comes with instructions on how to do the different rests in the mashing
(Protein Rest: 122° F for 20 minutes
Beta Sacch’ Rest: 149° F for 30 minutes
Alpha Sacch’ Rest: 158 F for 30 minutes etc),

but don't actually tell you how much of the mash to scoop out, boil and then return to the mash to achieve these temps. Any help on this?
The guy at NB said you can do a single step infusion for 60 min, and then a mashout if you want and it will be great - will it come out that much better using the protein developing step mash ?

mrsunshades said:

hEY, I was wondering if there is a calculation or formula for decoction mashing.
There is a kit from NorthernBrewer for a dunkelweizen (I asked you a question about that typy of ale earlier) Well the kit they sell comes with instructions on how to do the different rests in the mashing
(Protein Rest: 122° F for 20 minutes
Beta Sacch’ Rest: 149° F for 30 minutes
Alpha Sacch’ Rest: 158 F for 30 minutes etc),

but don't actually tell you how much of the mash to scoop out, boil and then return to the mash to achieve these temps. Any help on this?
The guy at NB said you can do a single step infusion for 60 min, and then a mashout if you want and it will be great - will it come out that much better using the protein developing step mash ?

Click to expand...

There are some formulas out there on the interwebs or in books like New Brewing Lager Beer by Greg Noonan.

Or, for lazy folks like me, just use BrewTarget and the mash designer does the cals for you and I have found the decoction temp calcs used in that SW to be very, very close every time.

My experience has been that decoction mashing is not worth the headache and anxiety over hitting target temps. If you're willing to relax and not worry so much about specific temps then it's a fine tool but no magic bullet.

The way to do it is to remove the thickest two thirds of the mash - a colander works well for this. Bring that to conversion temp, say 150ish, and hold for 10 minutes, then bring to a boil and add back to the mash. The enzymes are in the liquid, so the thin portion of the mash is not what you want to boil.

I would do this only once to go from protein rest to conversion temps. Doing it twice will be a royal pain (I've done it) and the process lacks the precision necessary to hit specific temps you have planned for beta and alpha rests.

I never did a side by side comparison using the same grain bill so I really can't say how much of an improvement it is but I can say it isn't black magic voodoo that will guarantee super fantastic beer. It is worth experimenting with though to see if you like it.

The more you do it the better you get at guessing how much mash to remove, personally I usually undershot my targets but the beer was no worse as a result.