Interesting German Brewing PDF

[Edelst0ff]

For what it's worth, W177 would be your traditional Kölsch yeast.

But why speculate? Give them a call, they are very friendly to deal with.

 

[Cavpilot2000]

A question about oxidation due to copper, since the literature and especially the low oxygen website so strongly suggest avoiding it:

While there is scientific rationale suggesting that wort reactions with copper can contribute to oxidation, has anybody actually experimented, using a DO meter to show the difference in O2 uptake using a copper immersion chiller vs, say, stainless steel? In other words, two otherwise identical brews, measuring DO prior to chilling and then after using the two most common types of immersion chillers.

Maybe the difference is dramatic, maybe it is slight, and maybe it is functionally non-existent or irrelevant at the temperatures/ volumes/ pH we are working with.

I'm not suggesting it isn't a factor, I'm just saying that before we all assume that copper is bad here, what evidence is there to back up that assertion that Fenton reactions take place under the conditions of wort chilling other than the assumption that they will?

Thoughts?

 

[Cavpilot2000]

One additional concern I have is this:
In the original document and in several other posts here, contributors talk about sulfur bombs if the right mix of SMB isn't achieved.
I am planning to try my hand at a low O2 German Pils as my first foray, but I don' want to go to all the trouble if it's going to be an iterative process where I may want to toss out my first few batches because because they reek of brimstone.

So are the SMB guidelines here a mid-range dose? A conservative dose? An aggressive dose?
What if I use a yeast that produces sulfur (which ages out eventually), am I risking creating a rotten egg pilsner?

I guess I understand everything is an iterative process where you strive for continual improvement, and maybe it's overstated, but reading the original document and several comments make me think you're rolling the dice the first time you try a LoDO recipe because you might end up with an undrinkable sulfur bomb.

Someone ease my concerns here.

 

[stpug]

One additional concern I have is this:
In the original document and in several other posts here, contributors talk about sulfur bombs if the right mix of SMB isn't achieved.
I am planning to try my hand at a low O2 German Pils as my first foray, but I don' want to go to all the trouble if it's going to be an iterative process where I may want to toss out my first few batches because because they reek of brimstone.

So are the SMB guidelines here a mid-range dose? A conservative dose? An aggressive dose?
What if I use a yeast that produces sulfur (which ages out eventually), am I risking creating a rotten egg pilsner?

I guess I understand everything is an iterative process where you strive for continual improvement, and maybe it's overstated, but reading the original document and several comments make me think you're rolling the dice the first time you try a LoDO recipe because you might end up with an undrinkable sulfur bomb.

Someone ease my concerns here.

As far as I've been able to gather, which has not been exhaustive, lager yeast strains are less likely to leave you with excessive sulfur character in the beer. You *should* have some sulfur remaining though, as that's one of the subtle characteristics of lager beers that makes them different (subtle, in this sense, may mean almost undetectable to very low levels that don't disrupt the enjoyment of the beer).

SMB levels you should target completely depend on how tight your process and system is. Assuming a semi-poor system, targeting about 40mg/l of SMB is a great starting point that should not result in excessive sulfur, and this should be fairly in-line with what the pdf suggests. With a much more tight system, you may only target 20-25mg/l levels. If you wish to ensure no residual sulfur (aside from yeast derived), then regardless of tightness of your system, target ~25mg/l levels (safe level). I personally believe there is incremental improvement with incremental change as you develop your own process and system.

I don't think you risk a dumper if you err on the side of caution; plus you get a glimpse into how it affects the overall final product. Then, next time you can choose to go heavier/lighter on dosing as you see fit.

As far as copper is concerned, I have no great input aside from the usual: "Warning: Sharks may be present in these waters". That doesn't guarantee you'll get bit, but the potential needs to be stated. I also use copper (as minimally as possible) in my process, and I still see improvement in beers.

 

[schematix]

A question about oxidation due to copper, since the literature and especially the low oxygen website so strongly suggest avoiding it:

While there is scientific rationale suggesting that wort reactions with copper can contribute to oxidation, has anybody actually experimented, using a DO meter to show the difference in O2 uptake using a copper immersion chiller vs, say, stainless steel? In other words, two otherwise identical brews, measuring DO prior to chilling and then after using the two most common types of immersion chillers.

Maybe the difference is dramatic, maybe it is slight, and maybe it is functionally non-existent or irrelevant at the temperatures/ volumes/ pH we are working with.

I'm not suggesting it isn't a factor, I'm just saying that before we all assume that copper is bad here, what evidence is there to back up that assertion that Fenton reactions take place under the conditions of wort chilling other than the assumption that they will?

Thoughts?

Here's the science...

http://www.lowoxygenbrewing.com/wp-content/uploads/2016/11/Metals-and-Beer-Stability.pdf

The metals catalyze reactions that result in free oxygen (i think, it's been a while since i took chemistry but that's what it looks like to me).

Just a thought.... anyone considered adding EDTA if using a copper chiller?

 

[Cavpilot2000]

And lastly, the Methods of the Low Oxygen Brewhouse article suggests that small amounts of Vienna or Munich malt combined with Pilsner malt can produce off-flavors.

WHAT?!?!?!?!?!?!

Since when????
Vienna and Munich malts are routinely combined with Pils malt for just about every kind of German beer.

Would anyone care to expand on that, because it sounds like pure nonsense.

 

[schematix]

And lastly, the Methods of the Low Oxygen Brewhouse article suggests that small amounts of Vienna or Munich malt combined with Pilsner malt can produce off-flavors.

WHAT?!?!?!?!?!?!

Since when????
Vienna and Munich malts are routinely combined with Pils malt for just about every kind of German beer.

Would anyone care to expand on that, because it sounds like pure nonsense.

The suggestion is to not use a small amount of vienna or munich in a predominantly Pils beer because the flavors come through to strong.

 

[Cavpilot2000]

SMB levels you should target completely depend on how tight your process and system is. Assuming a semi-poor system, targeting about 40mg/l of SMB is a great starting point that should not result in excessive sulfur, and this should be fairly in-line with what the pdf suggests. With a much more tight system, you may only target 20-25mg/l levels. If you wish to ensure no residual sulfur (aside from yeast derived), then regardless of tightness of your system, target ~25mg/l levels (safe level). I personally believe there is incremental improvement with incremental change as you develop your own process and system.

I don't think you risk a dumper if you err on the side of caution; plus you get a glimpse into how it affects the overall final product. Then, next time you can choose to go heavier/lighter on dosing as you see fit.

Thanks. That's exactly the kind of info I was looking for.

Here's the science...
http://www.lowoxygenbrewing.com/wp-content/uploads/2016/11/Metals-and-Beer-Stability.pdf
The metals catalyze reactions that result in free oxygen (i think, it's been a while since i took chemistry but that's what it looks like to me).

Thanks for that. I will read it in more detail when I can, but a cursory skim of it looks like it focuses on the commercial scale.
I would be really curious to see someone do an experiment to quantify O2 uptake from a copper IC, since that is the most common copper appliance used by homebrewers (especially an experienced low O2 brewer who has a tight process and can more precisely isolate the variable in question - hint, hint, gauntlet dropped).

I don't doubt the chemistry, I'm just curious about its impact on our scale as opposed to a commercial brewery scale.

It's funny, because in one of my old early homebrew books (maybe even Papazian - I don't know, I'd have to look for the source), there was a recommendation to incorporate copper, if possible due to the flavor enhancement it can provide. Oh how times change.

The suggestion is to not use a small amount of vienna or munich in a predominantly Pils beer because the flavors come through to strong.

Okay, that makes sense if that's the intent, but if that's the case, it wasn't phrased very well because it says they contribute "undesirable flavors", and it only references small amounts, which could be (was) interpreted as saying larger amounts are okay, but small amounts will just F things up. (for reference, the exact quote is:"Vienna and Munich malts blended in small amounts with Pilsner can add undesirable flavor elements as less Sodium Metabisulfite (NaMeta, SMB) is used").

What you say makes a lot more sense. Thanks for the clarification.

So would you think a half pound of Vienna in a Pils (5 gal) would present too strongly in a moderately low O2 brew?


Aaaaaand lastly, do any of you guys purge your transfer lines with CO2 prior to putting wort through them? I'm not sure its necessary, but I always do that when racking (and "purge-ish" my receiving vessels as well). It would be an easy habit t to ransfer.

 

[schematix]

Aaaaaand lastly, do any of you guys purge your transfer lines with CO2 prior to putting wort through them? I'm not sure its necessary, but I always do that when racking (and "purge-ish" my receiving vessels as well). It would be an easy habit t to ransfer.

I do. I connect them to my empty pressurized serving keg and then use my finger my press the poppet on the other end. When you total up the volume of the racking hose it's actually quite a bit....

 

[Cavpilot2000]

I do. I connect them to my empty pressurized serving keg and then use my finger my press the poppet on the other end. When you total up the volume of the racking hose it's actually quite a bit....

Thanks. What about on the hot side? That's where I was thinking more.

 

[schematix]

Thanks. What about on the hot side? That's where I was thinking more.

On the hot side i use the wort to push the air out of the hoses before i turn any pumps on. This is not only for aeration, but also because air bubbling through lines makes a big mess.

I typically open up the bottom drain on the source vessel and let the wort push the air out the other end of the hose. If you lift the other end above the liquid level it stops. Magic. Once the tube is full of wort then i connect it to the destination (or back to itself for recirc). There is only a small air-wort interface at that point.

When i rack to my FV i rack to the bottom and let it fill from the bottom up.

 

[stpug]

When i rack to my FV i rack to the bottom and let it fill from the bottom up.

When I rack to my FV I splash rack onto the surface of the liquid to incorporate air and help with yeast slurry mixing (which is already in my receiving FV). I've actually stopped using any pure O2 in favor of this method on standard gravity ales. Horses for courses, I guess

Lagers still supplemented with get pure O2, as do higher gravity ales.

 

[rabeb25]

And lastly, the Methods of the Low Oxygen Brewhouse article suggests that small amounts of Vienna or Munich malt combined with Pilsner malt can produce off-flavors.

WHAT?!?!?!?!?!?!

Since when????
Vienna and Munich malts are routinely combined with Pils malt for just about every kind of German beer.

Would anyone care to expand on that, because it sounds like pure nonsense.

Sure as those are my words, and the words of a few of us. I find small amounts of these malts (say 5% and below) just distracting when it comes to the beers. Vienna is really really doughy to me like fresh pizza dough, and munich comes across in small amounts as slighty sour and muddy. So I either add none or add enough so its there.. i.e. Festbier. But I personally do not like them in small amounts. A lot of people do, but the dough and twang are really apparent to me. I have been meaning to make a blog post on recipe formulation, cause I suspect its not what people are really used to. Malts taste different now (low oxygen), and we as Americans ave generally severely missed the mark on recreating recipes for German beers properly (myself included). According to the German brewing bibles (listed in our reference materials), Vienna is used to correct overpale malts, and festival beers. So you will find very few recipes with vienna in them.

As far as resources go, we have a very expansive library on the site... Should be enough to wet anyone's appetite.

 

[Cavpilot2000]

Sure as those are my words, and the words of a few of us. I find small amounts of these malts (say 5% and below) just distracting when it comes to the beers. Vienna is really really doughy to me like fresh pizza dough, and munich comes across in small amounts as slighty sour and muddy. So I either add none or add enough so its there.. i.e. Festbier. But I personally do not like them in small amounts. A lot of people do, but the dough and twang are really apparent to me. I have been meaning to make a blog post on recipe formulation, cause I suspect its not what people are really used to. Malts taste different now (low oxygen), and we as Americans ave generally severely missed the mark on recreating recipes for German beers properly (myself included). According to the German brewing bibles (listed in our reference materials), Vienna is used to correct overpale malts, and festival beers. So you will find very few recipes with vienna in them.

As far as resources go, we have a very expansive library on the site... Should be enough to wet anyone's appetite.

While I don't question your experience with low O2 brewing, I will suggest that it sounds like you are putting your personal palate and taste preferences up as fact instead of opinion.

I usually put 10% Vienna in my Helles, but no caramel malts because I prefer the dryer bready flavor provided by Vienna to the sweeter caramelized flavor of carahell, et al, to boost the plavor of the Pils malt. But that's my preference.
That said, I do not yet have experience with low O2 brewing enough to assess the claim that malts taste different (not just fresher) brewed via low O2 brewing. I look forward to trying it, and I will report back my results and perceptions for posterity.
Maybe my 10% Vienna Helles will be gross brewed low O2, maybe low O2 will amplify its glorious flavor. We'll see (but my first foray into low O2 will be a German Pils because my SWMBO's father is coming to visit from Germany and he loves a good Pils, so I owe him one).

 

[rabeb25]

I think you are looking too far Into it.
"Vienna and Munich malts blended in small amounts with Pilsner can add undesirable flavor elements as less Sodium Metabisulfite (NaMeta, SMB) is used (flavor intensity increases as system “tightness” increases)"
Is the exact quote..Can add. Doesn't say will add, I am not explicitly saying to not do it. Nor did I give you amounts.
Low oxygen flavors are not even close to normal flavors. In a nicely executed beer you can easily pick up 1% malt choice differences. I can pick up .5% roast malt in a beer. Non-oxidized low oxygen malts taste different. Nearly all commercial examples have cara malts in them. Helles is usually something like carahell( not caramelized flavor, it's beautiful fresh honey) or caramunich. Add 10% Vienna with it and you have a pretty stock helles recipe. Helles are usually made with 4ebc malt. We can't usually get 4ebc malt, but we can try and make it ourself using Vienna, Munich or pale ale malt. If your pils is 1.7ebc you need something to darken and make up the difference. Weihenstephan chooses to use carahell for the darkening of the base malts to the tune of about 8% for their helles, original. It's going to take trial and error for you. What was sweet and cloying ( typical oxidized cara's from HSA) will Not be anymore. I highly suggest doing low oxygen mini mashes with potential recipe formulations to get a feel for it.
It's all good. I understand the shock and awe. I was there 2+ years ago.

 

[Cavpilot2000]

I look forward to exploring the space of low O2.

I was reading too much into it, in light of your explanation, but that's why I asked for an explanation, because the statement by itself, to someone who is only just gaining familiarity with the process, is a shocking one and very counter to the experience of us "regular O2" brewers.
It also raises flags when you say something will contribute undesirable flavors without an explanation of what those off flavors are. Here I'm thinking it's going to add weird esters (at best) or perhaps even nasty, non-beer (truly undesirable) flavors.

You've got to forgive me, I've got a Masters degree in writing, so words mean things to me.
I just needed and explanation, which you kindly provided.
Thank you, sir.

 

[oujens]

I think you are looking too far Into it.
"Vienna and Munich malts blended in small amounts with Pilsner can add undesirable flavor elements as less Sodium Metabisulfite (NaMeta, SMB) is used (flavor intensity increases as system “tightness” increases)"
Is the exact quote..Can add. Doesn't say will add, I am not explicitly saying to not do it. Nor did I give you amounts.
Low oxygen flavors are not even close to normal flavors. In a nicely executed beer you can easily pick up 1% malt choice differences. I can pick up .5% roast malt in a beer. Non-oxidized low oxygen malts taste different. Nearly all commercial examples have cara malts in them. Helles is usually something like carahell( not caramelized flavor, it's beautiful fresh honey) or caramunich. Add 10% Vienna with it and you have a pretty stock helles recipe. Helles are usually made with 4ebc malt. We can't usually get 4ebc malt, but we can try and make it ourself using Vienna, Munich or pale ale malt. If your pils is 1.7ebc you need something to darken and make up the difference. Weihenstephan chooses to use carahell for the darkening of the base malts to the tune of about 8% for their helles, original. It's going to take trial and error for you. What was sweet and cloying ( typical oxidized cara's from HSA) will Not be anymore. I highly suggest doing low oxygen mini mashes with potential recipe formulations to get a feel for it.
It's all good. I understand the shock and awe. I was there 2+ years ago.

I find this very interesting. We have a local German brewery that makes the maltiest lagers I have tasted. There is what I call a "signature" flavor that I cannot taste in other beers. I have a friend that said the same thing. Not sure if they employ low oxygen brewing, but a lot of the comments here make me think its a possibility. One in particular was to use "very little" munich if brewing their lager which I think would be classified as a Helles. There is so much flavor I could swear they used more than a little. I would like to try brewing that again with low oxygen to see if I can pick up a similar flavor. Going to try to employ as much as I can on a brown ale tomorrow and go from there.

 

[TheHairyHop]

I find this very interesting. We have a local German brewery that makes the maltiest lagers I have tasted. There is what I call a "signature" flavor that I cannot taste in other beers. I have a friend that said the same thing. Not sure if they employ low oxygen brewing, but a lot of the comments here make me think its a possibility. One in particular was to use "very little" munich if brewing their lager which I think would be classified as a Helles. There is so much flavor I could swear they used more than a little. I would like to try brewing that again with low oxygen to see if I can pick up a similar flavor. Going to try to employ as much as I can on a brown ale tomorrow and go from there.

if you ever get a chance to go to Live Oak or get their beers on draft, both Primus and their Hefeweizen are excellent examples of the style. I don't like their cans though

 

[oujens]

if you ever get a chance to go to Live Oak or get their beers on draft, both Primus and their Hefeweizen are excellent examples of the style. I don't like their cans though

I went there last summer and always order a Hefe on tap. They have a great setup. Can't wait to go back with cooler weather and enjoy the outdoor area.

 

[rabeb25]

I look forward to exploring the space of low O2.

I was reading too much into it, in light of your explanation, but that's why I asked for an explanation, because the statement by itself, to someone who is only just gaining familiarity with the process, is a shocking one and very counter to the experience of us "regular O2" brewers.
It also raises flags when you say something will contribute undesirable flavors without an explanation of what those off flavors are. Here I'm thinking it's going to add weird esters (at best) or perhaps even nasty, non-beer (truly undesirable) flavors.

You've got to forgive me, I've got a Masters degree in writing, so words mean things to me.
I just needed and explanation, which you kindly provided.
Thank you, sir.

No worries, completely understand.

 

[TheHairyHop]

I went there last summer and always order a Hefe on tap. They have a great setup. Can't wait to go back with cooler weather and enjoy the outdoor area.

ah man, that seating area is wonderful. wish I was back there now, overfilling with BBQ and enjoying a Primus

 

[bierhaus15]

I would not read too deep into this low DO manifesto. Besides being mostly anecdotal, dubious at best, much of their info is based on studies done in the 1970's by Miller and Coors that were eventually refuted. Low DO brewing is a thing and does have many benefits, but replicating the same process on a home brew scale is not practical. The breweries that do this well are not brewing low DO beer for the sake of doing so, it is just another quality control point in their overall process. And adding Na2S2O5 to beer is NOT good practice. There are so many better antioxidants out there, if you feel you need them.... and most people do not!

 

[MaltMaker]

I would not read too deep into this low DO manifesto. Besides being mostly anecdotal, dubious at best, much of their info is based on studies done in the 1970's by Miller and Coors that were eventually refuted. Low DO brewing is a thing and does have many benefits, but replicating the same process on a home brew scale is not practical. The breweries that do this well are not brewing low DO beer for the sake of doing so, it is just another quality control point in their overall process. And adding Na2S2O5 to beer is NOT good practice. There are so many better antioxidants out there, if you feel you need them.... and most people do not!

1.) Can you point (or link) to the studies by Miller and Coors and their refutations?
2.) Why is adding Na2S2O5 to beer not good practice?
3.) What antioxidants are better and should be used instead?

 

[rabeb25]

1.) Can you point (or link) to the studies by Miller and Coors and their refutations?
2.) Why is adding Na2S2O5 to beer not good practice?
3.) What antioxidants are better and should be used instead?

As someone who is always trying to achieve perfection, I am interested in this as well.


I have many many papers that refute that, but I am always open to new ideas.

For Bierhaus- Here is some of my documentation- http://www.lowoxygenbrewing.com/uncategorized/list-of-brewing-references/

I look forward to yours!

 

[bierhaus15]

Frankly, I’m not going to take the time and dig through 50 years of WBC and MBAA material to find the papers. If you want to pay the 65 bucks for each WBC year, the material is there. That said, look at the Wallerstein papers on antioxidants and the dozens following from it, then go to the Molson/Miller work where they tested various antioxidants on aged and fresh beer. In short, antioxidants, including SMB, do have a positive effect on beer staling, but the effect is generally short lived and can cause issues with sulfur interaction with some beers. Moreover, early antioxidant studies were conducted mostly for the sake of pasteurized beer, where consumers would be drinking product up to a year after packaging. I don’t know many home brewers who pasteurize their beer, nor those who cannot gain more antioxidant benefit from having live yeast in their beer. I don’t claim to be an expert in DO/antioxidant use, but I’ve been in the industry long enough to know what is relevant to brewers less than 100,000 bbls.

Moreover, low DO mashing (not splashing, ect) is good practice, but adding SMB is not necessary for home brewers; it use skirts the more important issues like fermentation, storage, and packaging process. I think it was the Straub antioxidant paper (1989?) where it was determined that poor brewing practices negate almost all the effects of antioxidant use. If you can’t brew technically proficient beer to start, antioxidant use will not fix the base problems.

IMO, ascorbic acid and tannic acid (brewtan, ect) would be a safer and more practical antioxidant than SMB, especially when brewing Helles, where brewers go to great lengths to avoid adding sulfur to their brews.

My initial problem with the paper posted, was the almost complete lack of citations/source material. Moreover, these gems:

“You cannot make a proper Helles without employing a low oxygen brewing process.”

Please explain what a “proper” Helles is. I’ve been to many German and American breweries who make acclaimed Helles and many of them do so without SMB or intensive low DO brewing practices. In fact, most of them have good process control and mitigate DO through basic, proper brewing practices. Augustiner?

Moreover, please quantify “fresh malt flavor.” Is there an ASBC method I can use to measure what this is? How will I know I’ve lost it in the brewery when we measure our wort DO and its above 1ppm. Where is the evidence for this? Source material?

 

[ParanoidAndroid]

Looks like some coffee roasters are roasting and storing in low oxygen environments:

https://clivecoffee.com/2017/02/is-your-coffee-too-fresh/

“For our coffees, we roast them in a low oxygen environment (Loring roasters are closed systems) and all of our bags are nitrogen flushed and sealed for less than 1% residual oxygen and fitted with one-way valves allowing the CO2 to escape during the phase when the coffee is degassing. We’ve blindly cupped (sensory evaluated) coffees packaged in this low oxygen environment that were roasted 90 days before against the same coffee roasted 24 hours before and while a difference could be detected, there was not a very large delta between the two when scoring using the SCAA protocol. Aroma, flavor, acidity and sweetness are retained. However, aroma and flavor degradation is noticeable with coffees this old when stored in an environment of even 2%+ oxygen and very noticeable when stored in 20-21% oxygen (normal air).

 

[Magnus314]

One additional concern I have is this:
In the original document and in several other posts here, contributors talk about sulfur bombs if the right mix of SMB isn't achieved.

A lot of that talk was from me. I was doing full volume/no-sparge BIAB mashes, and using the "Strike Water" treatment level for all the water, and on top of that most of my beers then were ales using yeast that didn't clean up sulfur well.

After the guys set me straight, I've been consistently using 30mg/L for Ales and 40mg/L for Lagers without any excess sulfur smell or taste (and I'm extremely sensitive to sulfur), and making my best beers ever!

 

[Magnus314]

If i incorporate a couple of grams of Ascorbic Acid, should I adjust the (currently un-tasteable) level of SMB? Or add it in addition too?

Is there a precedent or formula or anything? I'm liking what I've been reading on the other forum about some of the commercially available anti-ox blends, and if a couple grams or so of vitamin C or tannic acid is going to make a positive difference, I'm all for it.

 

[stpug]

If i incorporate a couple of grams of Ascorbic Acid, should I adjust the (currently un-tasteable) level of SMB? Or add it in addition too?

Is there a precedent or formula or anything? I'm liking what I've been reading on the other forum about some of the commercially available anti-ox blends, and if a couple grams or so of vitamin C or tannic acid is going to make a positive difference, I'm all for it.

My understanding is that you would maintain the same mg/L dosages you're currently using, just split it 50/50 between SMB and AA. This effectively allows you half the amount of SMB you use in any given batch. However, you would not want to use AA without gallotannins in a system that includes copper (and/or reactive ferrous metals) in the process due to potential "super oxidizer" potential from the breakdown of the AA-metal reaction. If you don't have any copper (and/or reactive ferrous metals) in your system then it should not react and breakdown. If you are able to include gallotannins in your process then you can reduce both the SMB and AA dosage even more (only a little bit, but even a little is good).

Pick the dosage you like and the breakdown would be like this:
100% SMB
50/50% SMB/AA (systems without any reactive metals)
45/45/10% SMB/AA/Gallotannins (best oxidation protection)

 

[TexasWine]

My understanding is that you would maintain the same mg/L dosages you're currently using, just split it 50/50 between SMB and AA. This effectively allows you half the amount of SMB you use in any given batch. However, you would not want to use AA without gallotannins in a system that includes copper (and/or reactive ferrous metals) in the process due to potential "super oxidizer" potential from the breakdown of the AA-metal reaction. If you don't have any copper (and/or reactive ferrous metals) in your system then it should not react and breakdown. If you are able to include gallotannins in your process then you can reduce both the SMB and AA dosage even more (only a little bit, but even a little is good).

Pick the dosage you like and the breakdown would be like this:
100% SMB
50/50% SMB/AA (systems without any reactive metals)
45/45/10% SMB/AA/Gallotannins (best oxidation protection)

Let me make sure I have this straight. You're saying ff I used to target 50 mg/l SMB but I switch to a SMB/AA/BB blend, I should still target a total concentration of those three at 50 mg/l, which is about 0.19 g/gal?

I was going to just shoot for reducing my SMB down to around 35 mg/l until I read this. Plan is to use the 45/45/10 blend.