Decoction Advice

[HBHcustom]

I am looking into using a decoction mash for my next brew and was wondering if the following technique would be advisable:

I brew 10 gallon, all grain batches on a single tier, keg based electric brew rig.

My plan is to mash 2/3 of the grain in the regular fashion @67C and in a separate vessel mash the remaining 1/3. After the initial rest I plan to bring the smaller mash to a boil and add it back to the larger mash at mash out.

Anyone see any potential problems with this plan or do I simply pull the decoction grains from the primary mash and boil?

Thanks in advance.

 

[microbusbrewery]

Normally you pull from the main mash. The way I've always seen it done and the way I do it is pull 1/3 of the grains, leaving most of liquid behind. The idea is most of the enzymes are in the liquid, so by pulling the grain and leaving the liquid behind, you're not denaturing a 1/3 of the enzymes in the mash. I'm not 100% positive, but I believe another reason for pulling a thick decoction is in order to get the maillard reactions that you're after in decoction mashing and to ensure proper pH in the decoction. Brewing TV did a pretty good decoction segment back in the day. It's worth checking out, [ame]https://www.youtube.com/watch?v=IIQPQmELWPo[/ame]

 

[boasist]

As well, Northern put out a nice PDF. Page 2 is almost a written form of the video.

Here

 

[helterscelter]

I am looking into using a decoction mash for my next brew and was wondering if the following technique would be advisable:

I brew 10 gallon, all grain batches on a single tier, keg based electric brew rig.

My plan is to mash 2/3 of the grain in the regular fashion @67C and in a separate vessel mash the remaining 1/3. After the initial rest I plan to bring the smaller mash to a boil and add it back to the larger mash at mash out.

Anyone see any potential problems with this plan or do I simply pull the decoction grains from the primary mash and boil?

Thanks in advance.

I'm no expert.

my understanding is that decoctions are typically pulled from the mash, boiled and then added back to the mash.

edit: I believe the posters above are correct.. I hadn't considered the reason for pulling a thick mash for decoction when I suggested your method "should work". removed my faulty logic.. don't listen to me.

 

[microbusbrewery]

I'm not 100% positive, but I believe another reason for pulling a thick decoction is in order to get the maillard reactions that you're after in decoction mashing...

Just to clarify this point I mentioned, I meant you won't get the same amount of maillard reactions with "normal" mash consistency compared to a thick one (most liquid left behind). Think of cooking a piece meat in a frying pan with just a touch of liquid, compared to cooking a piece of meat, fully submerged in liquid (boiling) in same frying pan.

 

[triethylborane]

Normally you pull from the main mash. The way I've always seen it done and the way I do it is pull 1/3 of the grains, leaving most of liquid behind. The idea is most of the enzymes are in the liquid, so by pulling the grain and leaving the liquid behind, you're not denaturing a 1/3 of the enzymes in the mash. I'm not 100% positive, but I believe another reason for pulling a thick decoction is in order to get the maillard reactions that you're after in decoction mashing and to ensure proper pH in the decoction.

For my decoctions on a 5 gal batch, I pull 1.5 gallon of grain (using a strainer) and 1 gallon of grist (liquid/grain). It does wind up being about 1/3 of the total mash. It is thick, kind of like a slightly soupy grape nuts.


Malliard reactions can really benefit from a decoction. Wheat beers can benefit from a decoction mash as wheat proteins are complex viscoelastic (mostly gluten) chains that can withstand high temperatures without denaturing or lysing. A decoction mash is what will break down the wheat protein into shorter chains of amino acids that are beneficial for yeast reproduction. Likewise, wheat starches are broken down in a decoction that can react with the free amino acids for malliard reactions when brought to a boil and alpha amylase when back in the mash tun. Same goes if no wheat starches are present, it benefits the malliard reactions as there will be more free AA.

 

[triethylborane]

I am looking into using a decoction mash for my next brew and was wondering if the following technique would be advisable:

I brew 10 gallon, all grain batches on a single tier, keg based electric brew rig.

My plan is to mash 2/3 of the grain in the regular fashion @67C and in a separate vessel mash the remaining 1/3. After the initial rest I plan to bring the smaller mash to a boil and add it back to the larger mash at mash out.

Anyone see any potential problems with this plan or do I simply pull the decoction grains from the primary mash and boil?

Thanks in advance.

What is your grain bill/what are you brewing? I never do a split mash and I have always pulled the decoction mash from the main mash. But, you are correct after getting the decoction to a boil and holding it at boil for 10-15min (depending on what you are brewing), you add it back to the main mash.

 

[HBHcustom]

Thank you all for your insight - guess I'll do things the traditional way after all...