Decoction question

[jacksonbrown]

Is it really just as simple as pulling x amount of mash, boiling for 10-15, introducing it back to the tun, repeat?
I'd like to brew a dunkel this summer and use a decoction. I'd like to have a protein rest, sach rest, and mash out, so double decoction. Is that essentially all I need to know (aside from amounts to pull, which BeerSmith will tell me)?

 

[Pilgarlic]

NEED to know? Yeah, that's all you need to know. But if you WANT to know more I'd recommend taking a good look at Greg Noonan's classic "New Brewing Lager Beers" for a comprehensive treatment of decoction mashing.

 

[menschmaschine]

You need to pull a portion of the mash (i.e., a thick portion... mostly grain), bring it to 158°F and hold for 10 min. Then bring it to boiling and boil it for at least 5 min. (for lighter colored beers, longer for darker).

I'd recommend against doing a protein rest. With modern malts, it can do more damage than good. Do the first rest in the low to mid 140s°F, then decoct up to 156-158°F for the second rest. The mash out is up to you, but since it is a thin decoction (mostly liquid), it's only real purpose is to bring the main mash up to temp. This one you don't need to hold at 158°F like the first decoction. But if you have an easier means to bring the mash up to mash out temp., like direct heat, I wouldn't bother with a mash out decoction... in which case you would be doing a single decoction.

 

[Hammy71]

When I do a decoction, I boil for at least 30 minutes. Not sure where I read it, (probably a kaiser post I'm sure), but I think after the 30 minutes is when the magic happens, as far as flavor/body.

 

[jacksonbrown]

I've read a lot of the links and info Kaiser has put up, and I definitely take a look at "Lager Beers". I'm always up for a new book.
The only reason I was considering a protein rest is because it's a dunkelweizen. It was my understanding that protein rests are benefitial with wheats, even modern wheat malt. Is that not the case? Or could I do a protein rest on the wheat malt alone?

 

[menschmaschine]

I've read a lot of the links and info Kaiser has put up, and I definitely take a look at "Lager Beers". I'm always up for a new book.
The only reason I was considering a protein rest is because it's a dunkelweizen. It was my understanding that protein rests are benefitial with wheats, even modern wheat malt. Is that not the case? Or could I do a protein rest on the wheat malt alone?

Oh... DunkelWEIZEN. I thought you were brewing just a plain old Dunkel. I'm not that experienced with brewing with wheat, so I'm not sure about the protein rest. I think if it's malted wheat, you don't need the protein rest. Unmalted wheat, you do... or something like that.

 

[Fetus]

I'll preface this with a statement: Never tried a decoction mash. The process confuses me.

When you pull a portion of the mash, you're taking grain and liquid, and then boiling it? I was under the impression that boiling grain releases tanins from the husks. Is this not the case if the grain isn't completely submerged in liquid?

 

[Pilgarlic]

I believe that the pH of the boiled portion of the mash is at a low enough level that tannin extraction isn't a problem.

 

[zgardener]

I believe that the pH of the boiled portion of the mash is at a low enough level that tannin extraction isn't a problem.

I believe that is correct. I've done several decoctions, never had a tannin issue.
Most important thing with decocting is to stir constantly until the grains and wort start to boil then to stir often once the boil starts (or else the grains will begin to burn or caramelize). You'll notice that it will get really thick and sticky, keep stirring, and then it will all of a sudden get really thin and soupy, once it thins I stir every 3 to 5 minutes for about 20 min. This gives me a great malty profile without being too much and without impacting color too much.

 

[piteko]

The only reason I was considering a protein rest is because it's a dunkelweizen.

I made a pair of dunkelweizen (without decoction) and I made a protein rest of about 20 mins. If you make a standard decoction mash, the protein rest will be far longer than this and I think it will be too long even for a dunkelweizen.

I suggest you to use an enhanced decoction mash profile, as described here.

Good reading
cheers from Italy
Piteko