Decoction Mash Schedule for a Wee Heavy

[rippajak]

Hello, HBT.

I have been homebrewing for a couple of years now, and I have two or three dozen all-grain batches under my belt. Until this point, almost all of those brews have been single infusion mashes, with few double infusion or direct heat step-mashes for flavor. For my upcoming brew, a wee heavy, I would like to branch out and try my hand at a decoction mash. I have read that decoction mashing is a good technique to increase malt flavors and caramelization, which seems appropriate for the style. I am, however, unsure how to proceed.

The schedule I first drew up was as such:

• Mash in at an acid rest temperature of 95*F, rest there for 15 minutes.
• Pull a decoction, rest it at 150*F for 15 minutes, and boil it for 30 minutes. Raise the total mash temperature to 140*F and rest there for 20 minutes.
• Pull a decoction, rest it at 150*F for 15 minutes, and boil it for 10 minutes. Raise the total mash temperature to 158*F and rest there for 40 minutes.
• Pull a decoction, rest it at 150*F for 15 minutes, and boil it for 10 minutes. Raise the total mash temperature to 168*F and rest there for 5 minutes. Begin sparging.

My thinking was that this schedule would give the mash a short beta-amylase rest followed by a longer alpha-amylase rest. This would produce a lot of unfermentable sugars, giving the beer the thick mouthfeel and sweet maltiness that I'm looking for in a wee heavy. I deliberately avoided a protein rest, as I have read that using one with well-modified malts will result in a thin, watery beer.

I have since begun to doubt myself, especially considering the amount of extra time that would be spent at each rest while the decoction is prepared. I am afraid that the separate alpha and beta rests would result in too much sugar conversion, creating an end product that is overly dry. Would I be better served to cut it down to a double decoction, with a single saccharification rest around 152-154 followed by a mash-out? Is my fear of the protein rest unfounded?

Any advice is well-appreciated.

 

[didinho]

I have since begun to doubt myself, especially considering the amount of extra time that would be spent at each rest while the decoction is prepared. I am afraid that the separate alpha and beta rests would result in too much sugar conversion, creating an end product that is overly dry. Would I be better served to cut it down to a double decoction, with a single saccharification rest around 152-154 followed by a mash-out? Is my fear of the protein rest unfounded?

I'm a decoction fan. During years, I realized that you can get malty flavors, melanoidins also with a single step decoction, so I would do a protein rest (if required), a beta amilase step, then a single step decoction to bring te whole mash to alpha amylase temperatures. I did it recently for a barley wine (with 20% munich in the grist) and it turned out great!

 

[Dcpcooks]

You don't need to rest your decoction at a temp. The mash will take care of that for you. Your goal is to hit mash temps. Think of it like raising temps with hot water. The more you add the higher your mash temp will go to. What's your grain bill? A protein rest won't give you more sugar per se. It will allow you to convert unconverted gain (which will add sugars) and will break down protein so your mash won't gum up. It may not be necessary if you don't have wheat rye etc.

You rest temps will determine your sugar profile. Hitting that should be your goal.

 

[specharka]

Wouldn't use an acid rest or a protein rest on such a big beer. I like the 140-158-168 decoction mash schedule, though.

Another technique you can employ is to draw off about a gallon of first runnings and boil that down until it gets thick and syrupy, then combine it with the mash again. The Mailliard (sp?) reactions will create melanoidins, which further develop body and mouthfeel.

You don't need to rest your decoction at a temp. The mash will take care of that for you. Your goal is to hit mash temps. Think of it like raising temps with hot water. The more you add the higher your mash temp will go to. What's your grain bill? A protein rest won't give you more sugar per se. It will allow you to convert unconverted gain (which will add sugars) and will break down protein so your mash won't gum up. It may not be necessary if you don't have wheat rye etc.

You rest temps will determine your sugar profile. Hitting that should be your goal.

I agree with the first statement. The whole point of doing a decoction is the bulk of your mash is still converting starches, and will not be appreciably affected in fermentability once it is combined with the denatured decoction. The enzymes are still active.

Protein rests do nothing for starch conversion and saccharification. And without the presence of a significant amount (>30%) of wheat or rye, they will result in a thin, watery beer. I have done 21-22 lb mashes at 1.0 qt/lb without getting a stuck sparge. With well-modified malt, a protein rest is completely unnecessary.

Decoctions are also used in the brewing of traditional Pilsners (like Pilsner Urquell) to get body and mouthfeel without the use of adjunct.

 

[JimRausch]

If you're interested, here's the relatively simple decoction schedule that I use for my Lagers and Alts:
1. Start at 145-147. Hold there for 10 minutes then take 3qt thick decoction. Heat that to 158 and hold for 10 minutes. Then heat to boiling. I boil for 10 minutes or less.
2. Add the 3 qt back to the main mash which raises it to 158. Hold there for 20 minutes.
3. Vorlauf, drain and sparge. This schedule works well for me and gives a total mashtime of 75 minutes or so.
By the way, one trick I picked up in doing a Wee Heavy a few years ago(and a Dopplebock I did the same year) is to take the 1st gallon runnings and boil that down separately to really concentrate it before adding back at flameout. Increases the melanoidins and gives an malty backbone.

 

[munja]

By the way, one trick I picked up in doing a Wee Heavy a few years ago(and a Dopplebock I did the same year) is to take the 1st gallon runnings and boil that down separately to really concentrate it before adding back at flameout. Increases the melanoidins and gives an malty backbone.

For how long did you boil this separated wort?

 

[munja]

By the way, one trick I picked up in doing a Wee Heavy a few years ago(and a Dopplebock I did the same year) is to take the 1st gallon runnings and boil that down separately to really concentrate it before adding back at flameout. Increases the melanoidins and gives an malty backbone.

How long this separated wort boiled?

 

[didinho]

How long this separated wort boiled?

until it gets a dense and sticky syroup

 

[rippajak]

I'm glad to hear that it is unnecessary to rest the decoctions at conversion temperature. Several tutorials on decoction mashing that I have read recommend doing it, but it seemed redundant with actually mashing the entire volume. Add to that the extra time on an already lengthy brew day, and I'm definitely not sorry to see that step go.
It sounds like the acid and protein rest can both go, too?
I'm thinking now that I'll just do a double decoction, with rests at 140* and 158*, followed by a mash out at 168*. That will make for a much shorter brew day, which is a plus. Thoughts?

I like the sound of boiling down the first runnings. Unfortunately I only have one burner in my brew space, and the kitchen is much too far away to effectively keep eyes on both. Maybe I'll try to get a hold of a little camp stove or something to run beside my main burner.

 

[JimRausch]

Yes, the last time I did the boil-down thing , I used a coleman stove next to my setup in the garage. Boiled it separately for the 60 minutes I was boiling the main batch, then added it back.
Also, I would skip the mashout step. Really not necessary, and it'll save you even more time.

 

[JohnSand]

Thanks for sharing your experience. I'm looking at decoction, but don't want to mash for hours.

 

[Oginme]

By the way, one trick I picked up in doing a Wee Heavy a few years ago(and a Dopplebock I did the same year) is to take the 1st gallon runnings and boil that down separately to really concentrate it before adding back at flameout. Increases the melanoidins and gives an malty backbone.

I perform a side kettle reduction for my Scotch ale. Use a candy thermometer. The water will boil off at 211F to 212F during the first part of the reduction. Once any free water is gone, the temperature will start to rise again. I usually stop and hold it at around 340 F for about 10 minutes. Honestly, I get nervous about scorching at this point or I would be tempted to take it longer. You will end up with a very thick paste at this point.

At the end of the boil, I remove about 1 liter of hot wort and put it into my pot with the caramelized 1st runnings. Stir and scrape the heavy paste off the bottom of the pot and mix into the wort. It is the easiest way I have found to clean out the pot and get the most of the caramelized wort transferred.