Extra enzymes for partial mash

[MrFancyPlants]

I was looking at doing a stout recipe that has oats and flakes barley and some other steeping grains.
My main fermentable will be DME, and I was wondering if alpha amylase will be enough to mash the grain bill, or do I need beta or glucoamalyse also?

I love stouts, but never brewed one before.

recipe:Yoopers Oatmeal Stout

 

[VikeMan]

You also need beta amylase and limit dextrinase as well as alpha amylase. And glucoamylase would probably make the wort too fermentable unless you really have dialed in the amount to use.

The best thing would be to do a true partial mash, i.e. "steep" your grains along with an equal amount of base malt (pale malt or pilsner) for 30-60 minutes at a temperature of about 150-155F.

 

[MrFancyPlants]

How about malted oats? Do they have comparable enzyme to 2/row?

 

[VikeMan]

How about malted oats? Do they have comparable enzyme to 2/row?

No. Malted Oats have a diastatic power of about 25 degrees L. 30 if you're lucky. A typical 2-row brewer's malt will be about 130-140 degrees L.

 

[BrewnWKopperKat]

I love stouts, but never brewed one before.

Yoopers Oatmeal Stout

Let's "tag" @Yooper to see if there's an existing partial mash version of the recipe.

eta (about a day later): there's a thread from 2010, also titled Yooper's Oatmeal Stout (link) which includes some ideas on a partial mash recipe.

 

[tracer bullet]

The best thing would be to do a true partial mash, i.e. "steep" your grains along with an equal amount of base malt (pale malt or pilsner) for 30-60 minutes at a temperature of about 150-155F.

This for sure. For some extract / DME recipes you can soak dark grains a bit on their own, get some color and flavor, and it works. By the time you start adding more and more to it, and becoming an all-grain batch, you sort of have to start doing all-grain practices.

You can still use a bunch of extract or DME of course, to minimize the size or workload.

 

[BrewnWKopperKat]

@MrFancyPlants : this recipe is also in a long running thread from 2010 ( Yooper's Oatmeal Stout (link)) which includes some discussion on partial mash recipes.

 

[Brooothru]

You also need beta amylase and limit dextrinase as well as alpha amylase. And glucoamylase would probably make the wort too fermentable unless you really have dialed in the amount to use.

The best thing would be to do a true partial mash, i.e. "steep" your grains along with an equal amount of base malt (pale malt or pilsner) for 30-60 minutes at a temperature of about 150-155F.

This is exactly what I planned to do with my 'retro' partial grain batch. It's an English bitters that will use Maris Otter LME. I'll be mini-mashing one pound of M.O. with one pound of Victory and a half pound of acidulated. The Victory should have enough enzymes to self-convert, but I've considered subbing it with Munich II. I also thought about mashing-in around 125F, dosing with glucoamylase for 5-10 minutes, then raising the mini-mash temperature above 140F to denature it. Normal dosing for amylo is 1/2 tsp per 6 gallons, so I'd really have to micro-dose it. I can always add maltodextrin if the wort gets too thin.

 

[Miraculix]

This is exactly what I planned to do with my 'retro' partial grain batch. It's an English bitters that will use Maris Otter LME. I'll be mini-mashing one pound of M.O. with one pound of Victory and a half pound of acidulated. The Victory should have enough enzymes to self-convert, but I've considered subbing it with Munich II. I also thought about mashing-in around 125F, dosing with glucoamylase for 5-10 minutes, then raising the mini-mash temperature above 140F to denature it. Normal dosing for amylo is 1/2 tsp per 6 gallons, so I'd really have to micro-dose it. I can always add maltodextrin if the wort gets too thin.

Half a pound of acidulated? For what? I use about 60 grams per batch for mash pH correction. Do you want to make a sour?

 

[Brooothru]

Half a pound of acidulated? For what? I use about 60 grams per batch for mash pH correction. Do you want to make a sour?

Naw. My source water is fairly alkaline. I haven't run the final numbers thru a calculator yet, but my 'normal' baseline recipes start with a quarter to 1/2# of acidulated to get my mash in the 5.4-5.6 pH range. I usually have to acid lactic to the late boil to get pH down to 5.0-5.2. It may be less of a concern using LME.

 

[Miraculix]

Naw. My source water is fairly alkaline. I haven't run the final numbers thru a calculator yet, but my 'normal' baseline recipes start with a quarter to 1/2# of acidulated to get my mash in the 5.4-5.6 pH range. I usually have to acid lactic to the late boil to get pH down to 5.0-5.2. It may be less of a concern using LME.

How big are your batches? this sounds like an awfully huge amount of acidulated malt! A rule of thumb that works for water with a medium to higher alkalinity is using 1.5% to 3% of the total grist as acidulated malt in weight. If you are doing partial mashes, only the weight of the partial mash counts.

 

[VikeMan]

I'll be mini-mashing one pound of M.O. with one pound of Victory and a half pound of acidulated. The Victory should have enough enzymes to self-convert, but I've considered subbing it with Munich II.

Some sources (without saying where they got the information) say Victory has a Diastatic Power of 50 degrees Lintner. Others say 0. I'm inclined to think it's closer to 0, given the high degree of kilning and the fact that Briess makes no claims about any DP for Victory.

I don't know where the claim of 50 deg L got started, but I'd almost be willing to bet a paycheck it wasn't Briess.

But someone should try doing a SMaSH beer with Victory, for science.

 

[BrewnWKopperKat]

I'm curious as to how this comes out ...

This is exactly what I planned to do with my 'retro' partial grain batch. It's an English bitters that will use Maris Otter LME. I'll be mini-mashing one pound of M.O. with one pound of Victory and a half pound of acidulated [malt]. The Victory should have enough enzymes to self-convert, but I've considered subbing it with Munich II. I also thought about mashing-in around 125F, dosing with glucoamylase for 5-10 minutes, then raising the mini-mash temperature above 140F to denature it. Normal dosing for amylo is 1/2 tsp per 6 gallons, so I'd really have to micro-dose it. I can always add maltodextrin if the wort gets too thin.

Naw. My source water is fairly alkaline. I haven't run the final numbers thru a calculator yet, but my 'normal' baseline recipes start with a quarter to 1/2# of acidulated to get my mash in the 5.4-5.6 pH range. I usually have to acid lactic to the late boil to get pH down to 5.0-5.2. It may be less of a concern using LME.

... as this is probably the most complex partial mash process that I've seen.

 

[BrewnWKopperKat]

@MrFancyPlants : Another idea that shows up in the long running thread ( Yooper's Oatmeal Stout (link) ) is substituting ingredients that should be mashed with similar ingredients that don't need to be mashed. For example, some people reported good results with Golden Naked Oats (link to product info).

 

[Brooothru]

Some sources (without saying where they got the information) say Victory has a Diastatic Power of 50 degrees Lintner. Others say 0. I'm inclined to think it's closer to 0, given the high degree of kilning and the fact that Briess makes no claims about any DP for Victory.

I don't know where the claim of 50 deg L got started, but I'd almost be willing to bet a paycheck it wasn't Briess.

But someone should try doing a SMaSH beer with Victory, for science.

Uhmmm. I think I'll pass on that one.

 

[Brooothru]

I'm curious as to how this comes out ...





... as this is probably the most complex partial mash process that I've seen.

Yeah, sometimes I probably swing too much for the fences. Go big or go home, I guess. But why make things simple.

 

[VikeMan]

Yeah, sometimes I probably swing too much for the fences. Go big or go home, I guess. But why make things simple.

Maybe bunt this one instead of swinging for the fences? IOW, I would calculate the acid malt requirement. All other things being equal, it won't be the same as you full mashes' acid malt requirement.

 

[Brooothru]

Maybe bunt this one instead of swinging for the fences? IOW, I would calculate the acid malt requirement. All other things being equal, it won't be the same as you full mashes' acid malt requirement.

I ran the numbers for a full volume mash with grains + extract, but should I leave "fermentables" without accounting for extract? (i.e., grains only?). Not sure if that would make a difference.

That was using my well water as source. When I ran it using distilled water, the salt additions were only a few grams of CaSO4, CaCl, and NaCl to get a "Light&Malty" water profile, so the culprit is no doubt my well source water. Residual alkalinity runs high with this one.

 

[VikeMan]

I ran the numbers for a full volume mash with grains + extract, but should I leave "fermentables" without accounting for extract? (i.e., grains only?). Not sure if that would make a difference.

I don't know what your software does, but it shouldn't be using any information about LME/DME in the mash pH calculation.

 

[BrewnWKopperKat]

Yeah, sometimes I probably swing too much for the fences. Go big or go home, I guess. [...]

Changing may things at the same time can be a good way to get to a new "starting point" - so what you're trying, while uber-advanced, is interesting.

 

[IslandLizard]

I'll be mini-mashing one pound of M.O. with one pound of Victory and a half pound of acidulated. The Victory should have enough enzymes to self-convert, but I've considered subbing it with Munich II.

I've never heard of a Victory (or any Biscuit type) malt having DP of its own...

Make sure to double check the DP of the MO you're using. Many British MO malts have lowish DP. E.g., Simpsons lists theirs at 45-70°L. So, 1 pound of MO won't be able to convert 1 pound of adjunct. If using Munich II ("Dark Munich") instead of Victory you should be just OK, it can convert itself, but barely.

 

[Brooothru]

I don't know what your software does, but it shouldn't be using any information about LME/DME in the mash pH calculation.

It's the Advanced Water Calculator on this website. I use the pull-down menu to enter the grist bill with the type of malt and its Lovebond. For LME I just entered it as base malt with weight and color. I read (I believe on this forum) that the processing of wort into LME and spray malt leaves the mineral content of the wort behind. What that is unclear if I need to calculate mineral additions based solely on volume and chemistry of the water, or the water plus grist, or water plus grist plus extract. I'm guessing that it's probably water alone, since grist has less affect on wort mineralogy and extract even less if any.

 

[VikeMan]

It's the Advanced Water Calculator on this website. I use the pull-down menu to enter the grist bill with the type of malt and its Lovebond. For LME I just entered it as base malt with weight and color. I read (I believe on this forum) that the processing of wort into LME and spray malt leaves the mineral content of the wort behind. What that is unclear if I need to calculate mineral additions based solely on volume and chemistry of the water, or the water plus grist, or water plus grist plus extract. I'm guessing that it's probably water alone, since grist has less affect on wort mineralogy and extract even less if any.

Ah, for mash pH purposes, don't pretend that LME is a malt, unless you're planning to include the LME in the mash.

For LME's mineral contributions... i.e. not for the mash but for the overall profile after the LME is added, you'd need to know what the manufacturer's water looked like. I think @BrewnWKopperKat (IIRC) may have some links that would help with that.

And yes, for "water profile" purposes, ignore the fact that malt contains minerals.

 

[BrewnWKopperKat]

The articles / spreadsheets / podcasts / books I have for references offer some general observations on mineral content, but nothing that translates directly into ppm that can be put into an existing water chemistry spreadsheet or web site.

If I get back to using partial mash techniques, I would likely approach it this way:

• "stove top" brewing (I have an induction cooktop)
• "wort a/b" concept (How to Brew, 4e)
• a full partial mash ("wort a" is a 50% of the fermentables), not a mini-mash
• water adjustments for "wort a" would use common water chemistry software
• initially, exclude "wort b" and the DME/LME from water adjustments, ...
• ... with the intent of adding minerals to the glass to fine tune the recipe.

eta: This approach assumes source water is suitable for DME/LME ("low mineral"). IIRC, there is a short section in How To Brew, 4e that suggests values upper limits for "low mineral" water (including alkalinity).

 

[Brooothru]

Ah, for mash pH purposes, don't pretend that LME is a malt, unless you're planning to include the LME in the mash.

For LME's mineral contributions... i.e. not for the mash but for the overall profile after the LME is added, you'd need to know what the manufacturer's water looked like. I think @BrewnWKopperKat (IIRC) may have some links that would help with that.

And yes, for "water profile" purposes, ignore the fact that malt contains minerals.

The articles / spreadsheets / podcasts / books I have for references offer some general observations on mineral content, but nothing that translates directly into ppm that can be put into an existing water chemistry spreadsheet or web site.

If I get back to using partial mash techniques, I would likely approach it this way:

• "stove top" brewing (I have an induction cooktop)
• "wort a/b" concept (How to Brew, 4e)
• a full partial mash ("wort a" is a 50% of the fermentables), not a mini-mash
• water adjustments for "wort a" would use common water chemistry software
• initially, exclude "wort b" and the DME/LME from water adjustments, ...
• ... with the intent of adding minerals to the glass to fine tune the recipe.

eta: This approach assumes source water is suitable for DME/LME ("low mineral"). IIRC, there is a short section in How To Brew, 4e that suggests values upper limits for "low mineral" water (including alkalinity).

Thanks for the recommendations. Your summary is pretty much what I intuitively thought, but didn't know how exactly to quantify. Thinking (and calculating) final wort as the sum of Worts A and B is clearly the path to follow while probably being obsessive behavior on a home brew level. Sometimes I have to redouble my efforts to keep OCD in check.

 

[VikeMan]

Thanks for the recommendations. Your summary is pretty much what I intuitively thought, but didn't know how exactly to quantify. Thinking (and calculating) final wort as the sum of Worts A and B is clearly the path to follow while probably being obsessive behavior on a home brew level. Sometimes I have to redouble my efforts to keep OCD in check.

I think you already know this, but just be sure not to "sum" worts A and B for mash pH computation purposes. Stuff that doesn't partcipate in the mash doesn't affect the mash pH. (But the "sum" does affect overall water mineral profile.)