Introduction to Low Oxygen Brewing

[jonhughey_att.net (HoosierBrew)]

@mabrungard

I expect that it would still be useful and telling in a qualitative or relative way. Trials run with and without DO reduction measures could probably be assessed to some degree.

That was my thought, too.

As a person with a DO meter I can certainly tell you that mashes with low oxygen measures and those without, do not register even close to the same readings. Now, how accurate is it in low oxygen worts I can’t speak to that. But going from 4ppm normal to .2-.3 low oxygen is enough of a difference for myself.

Yeah that was what I was getting at, ie, something to use as a ‘with lodo measures vs without’ measurement. Looks like a pretty significant difference in measurements to me.

[system]

For me it was pretty easy to equate numbers to results. For instance as I mentioned above:

Standard mash 4-5ppm
Preboil only 2-3ppm
Preboil+SMB .2-.3ppm

Flavor loss happened about 1ppm.

So while I will concede they may not be actual DO wort values, they were able to easily correlate for me and then others with the same meters saw the same results as well. That was suffice for me.

[brewinhard]

@lupulus

• Sulfites may not be the solution for ales. My personal observations are that even at 30ppm SMB in the mash, they can be perceived in the final beer as either sulfite or sulfide flavors. More data is need, but I stopped using them for ales (except for weissbier yeast). I think the effect is yeast dependent and not temperature dependent because I did not notice it either a weissbier or a dampfbier, but again more data is needed.

Has anyone else noticed this excess flavor when using SMB in conjunction with ale yeasts and their subsequent fermentations?

If so, has anyone tried simply just a pre-boil and spunding to counteract oxygen ingress?  It sounds like the low SMB addition still really seems to be the way to negate additional ppm of oxygen in the mash.

[natebrews]

I have done 2 ales using a LODO mashing regiment.  Both batches were fermented with english ale yeast (1968 for one, Lallemand London ESB for the other) and the first had a definite bite to it that I had not experienced before.  The second batch was a Bitter that I make a lot, and this one was very sulfury (eggs and farty), which I have never experienced with this beer before.

Granted, the data isn’t very good since the second one was using a new yeast and the first was using a new hop.  Really, I should make that bitter again and use 1968 to ferment it since I have a lot of experience with that recipe.

[brewinhard]

@natebrews

The second batch was a Bitter that I make a lot, and this one was very sulfury (eggs and farty), which I have never experienced with this beer before.

I am assuming this was from a high SMB addition?  These were not spunded either, correct?

Did the sulfur ever dissipate?

[natebrews]

As a separate question, do you have any gauge for when the extraction of these delicate flavor compounds occurs?  For example, if I’m doing a mash where I batch sparge, am I getting most of those compounds out in the first runnings and the subsequent runnings are not pulling those (and so may not require as tight a control of the O2 pickup)?

In such a case, if I had the first running in the kettle and brought them up to a boil (or just below) to keep O2 from diffusing into the liquid and then ran the second runnings out slowly at a rate such that the heater could keep up and drive any dissolved gasses out of solution upon contact with the main liquid mass?

I’m just trying to think of ways that people can more effectively use the system they currently have (ok, the system I currently have) to get the best results.  My system definitely leans toward batch sparging, though I have fly sparged before.  When I fly sparge though, I have used a Blichmann autosparge which drips and gurgles and crap all the time.

[natebrews]

@brewinhard

@natebrews

The second batch was a Bitter that I make a lot, and this one was very sulfury (eggs and farty), which I have never experienced with this beer before.

I am assuming this was from a high SMB addition?  These were not spunded either, correct?

Did the sulfur ever dissipate?

The second one was spunded, the first one was not.  The sulfur has gone down notably from before, but it is still offensive.  I might just force carb it to a high level and then blow off the carbonation to scrub that sulfur out of it.  The beer that lurks under the sulfur character definitely has a different taste than the standard version of the thing.

[jonhughey_att.net (HoosierBrew)]

The lodo APA with 1056 I just did used 50ppm SMB, no spunding. There was no sulfur, no sulfite bite. I found overall quality to be quite good, with the 7% C40 and 20% MO surprisingly vibrant and more defined. O think the real trick is in dialing in the amounts for your system as you tighten up the process. $0.02. .

[natebrews]

I’m sure, I have only tried 3 batches using that method and none of them were the same thing.  I think what I need to do is make the same beer a few times in a row with it to get it dialed in.  I have had a lot of headaches just in the “how do I use my setup to accomplish the task” problems, since my regular method is generally incompatible with the low do mashing.

For example, I haven’t gotten the infusion temperature method quite right and my temps have been off a few degrees.  Since you can’t stir up the mash, I’m not sure how one would go about infusing hot/cold water (or mineral adjustments) and get them to be evenly distributed in the mash.  Consequently, I haven’t been adjusting things the way I usually do. (I’m doing infusion in a cooler)

For reference, I was using 50ppm.

[hopfenundmalz]

@hopfenundmalz

@hopfenundmalz

@lupulus

@mabrungard

The Hamilton VisiTrace DO probes are reported to sense 0 to 2 ppm DO at temps up to 85C. That would suffice for mash use. I was lusting after them at last year’s CBC but the $2k price tag was too much for me.

Thanks Martin for taking the time to write.
I would love to see the validation tests this company has run.
I am a bit suspicious because many researchers have indicated that measuring DO in the mash is not directly possible, and none of the published data uses a DO meter.

In the Stability of Beer chapter of the Handbook of Brewing, 2012, August Gresser writes: It is known that oxygen at higher temperatures reacts with polyphenols, anthocyanes and tannoids. Brighter beers that are richer in polyphenols are more sensitive to oxygen in comparison with medium - colored beer and, especially, darker beers. For this reason, the brewer should carefully monitor the presence of oxygen with instruments during wort filtration and also during mashing, wort boiling or in general in the field of higher temperatures. Oxygen cannot be determined during the mashing process – one can take values from empirical procedures…

In Enzymic and Non-Enzymic Oxidation in the Brewhouse,  1999, Bamforth states:
An additional complication concerns the assessment of oxygen consumption at this stage in the process. Direct measurement of oxygen in mash is fraught with difficulty and most people have reverted to redox measurements (using redox probes or colorimetric techniques) to gain an indication of the extent of oxidative damage. The interpretation and relevance of such measurements is by no means straightforward.

The Gresser quote is of interest. It fits some of my taste experiences in Germany.

Kunze touches on it as well( chapter 2 I think, malt section). The dark malts and beers having more oxygen reduction potential.

Do hops cover up the oxidized malt flavor? The Franconian Helles that I have had are more hoppy than around Munich. Some will not have any trace of oxidized flavors others you get something in the first sip, then you taste the flavor hops on the second sip. Third sip you say, what was that flavor?

I suppose they could depending how late the hops were added, and how much flavor they have in the beer. What are the oxidized flavors you are seeing? Honey?

Oxidized is my best description, maybe a little beyond paper, not cardboard. Not clean and sweet.

[system]

Ahh ok. So starting the phases.

[system]

Looks like I missed quite a few posts.  So see if I can recap and shed some light.
Too much sulfur in ales.  Yea it’s a touchy area and all yeast and their sulfite tolerance will be different. For instance I use us05 and my dose of 30ppm does not yield me any sulfur or off flavors. There is an answer though and that answer is to augment SMB with ascorbic. I would try and keep your SMB dose at or around    30ppm and maybe try 20ppm ascorbic. I tried not to talk much about this on purpose cause I don’t think we are quite there yet as a group. Again though this is going to be system and yeast dependent. I hate to throw another variable into the mix.

[jonhughey_att.net (HoosierBrew)]

Looks like I missed quite a few posts.  So see if I can recap and shed some light.
Too much sulfur in ales.  Yea it’s a touchy area and all yeast and their sulfite tolerance will be different. For instance I use us05 and my dose of 30ppm does not yield me any sulfur or off flavors. There is an answer though and that answer is to augment SMB with ascorbic. I would try and keep your SMB dose at or around    30ppm and maybe try 20ppm ascorbic. I tried not to talk much about this on purpose cause I don’t think we are quite there yet as a group. Again though this is going to be system and yeast dependent. I hate to throw another variable into the mix.

So the ascorbic in the presence of SMB is no longer a potential super-oxidizer, I assume?

[homoeccentricus]

Cf Antioxin sbt? https://www.homebrewersassociation.org/forum/index.php?topic=28249.msg369032#msg369032

[system]

Looks like I missed quite a few posts.  So see if I can recap and shed some light.
Too much sulfur in ales.  Yea it’s a touchy area and all yeast and their sulfite tolerance will be different. For instance I use us05 and my dose of 30ppm does not yield me any sulfur or off flavors. There is an answer though and that answer is to augment SMB with ascorbic. I would try and keep your SMB dose at or around    30ppm and maybe try 20ppm ascorbic. I tried not to talk much about this on purpose cause I don’t think we are quite there yet as a group. Again though this is going to be system and yeast dependent. I hate to throw another variable into the mix.

So the ascorbic in the presence of SMB is no longer a potential super-oxidizer, I assume?

Yea the jist of it is, Meta is going to be your fast reagent, he is going to be out on the hunt for o2, and will break it down almost immediately, splashing and dough in. AA is going to be the bouncer at the door saying, “sorry you can’t come in here” to surface and slow diffusions. AA is not going to be able to keep up with a fast intrusion.

[jonhughey_att.net (HoosierBrew)]

Looks like I missed quite a few posts.  So see if I can recap and shed some light.
Too much sulfur in ales.  Yea it’s a touchy area and all yeast and their sulfite tolerance will be different. For instance I use us05 and my dose of 30ppm does not yield me any sulfur or off flavors. There is an answer though and that answer is to augment SMB with ascorbic. I would try and keep your SMB dose at or around    30ppm and maybe try 20ppm ascorbic. I tried not to talk much about this on purpose cause I don’t think we are quite there yet as a group. Again though this is going to be system and yeast dependent. I hate to throw another variable into the mix.

So the ascorbic in the presence of SMB is no longer a potential super-oxidizer, I assume?

Yea the jist of it is, Meta is going to be your fast reagent, he is going to be out on the hunt for o2, and will break it down almost immediately, splashing and dough in. AA is going to be the bouncer at the door saying, “sorry you can’t come in here” to surface and slow diffusions. AA is not going to be able to keep up with a fast intrusion.

Cool, thanks for the info.

[system]

Looks like I missed quite a few posts.  So see if I can recap and shed some light.
Too much sulfur in ales.  Yea it’s a touchy area and all yeast and their sulfite tolerance will be different. For instance I use us05 and my dose of 30ppm does not yield me any sulfur or off flavors. There is an answer though and that answer is to augment SMB with ascorbic. I would try and keep your SMB dose at or around    30ppm and maybe try 20ppm ascorbic. I tried not to talk much about this on purpose cause I don’t think we are quite there yet as a group. Again though this is going to be system and yeast dependent. I hate to throw another variable into the mix.

So the ascorbic in the presence of SMB is no longer a potential super-oxidizer, I assume?

Yea the jist of it is, Meta is going to be your fast reagent, he is going to be out on the hunt for o2, and will break it down almost immediately, splashing and dough in. AA is going to be the bouncer at the door saying, “sorry you can’t come in here” to surface and slow diffusions. AA is not going to be able to keep up with a fast intrusion.

Cool, thanks for the info.

I guess I missed the important part, when AA is greeted with larger amounts of 02, thats when it will superoxidize. Meta for large and quick, and to knock out the bulk, AA for the low and slow.

[lupulus]

I appreciate that Bryan (@Beerery) is trying to simplify the discussion, but in doing so we may be simplifying too much and making too many assumptions.

START OF CHEMISTRY BRIEF
Here some statements that the group should feel free to correct/ improve

• Oxidation-reduction reactions are within the realm of what some have called RedOx chemistry. Here are
  some definitions:

• oxidation is loss of e−
• reduction is gain of e−
• oxidizing agent gains e− during reaction and is therefore reduced during reaction
• reducing agent loses e− during reaction and is therefore oxidized during reaction
• oxidized form form of molecule relatively lacking an e−
• reduced form form of the molecule relatively having an additional e−
  A molecule with a higher negative redox potential than another molecule will tend to lose electrons (i.e. to be oxidized by reducing another molecule, eg. a free radical) more than a molecule with a lower negative redox potential; and a molecule with a higher positive redox potential will tend to gain electrons (i.e. to be reduced by oxidizing another molecule).
  These reactions are of course dependent on the concentration of the reacting molecules, concentration of other molecules that can reduce/oxidize, the pH of the solution, and the temperature of the solution
  END OF CHEMISTRY BRIEF

We do not know whether the redox potential of SMB in mash conditions is higher than that of ascorbic acid (it would be my working hypothesis that SMB is a better antioxidant but again, there is no data in our experimental conditions). Remember that SMB will be mostly in the sulfite form under mash conditions, so we cannot use data collected when it was mostly in the sulfite form (at higher pH).
I also agree it is a fair working hypothesis that dehydroascorbic acid (oxidized ascorbic acid) is more prone to regain the lost electron by oxidizing another molecule vs oxidized bisulfite; but again, this is not proven either. It may even be different for L- vs D-ascorbic acid.
If you add gallotanins (Brewtan) to the equation, it will get even more complicated

Bottom line

• it is not proven that mole to mole, SMB is better than ascorbic acid in mash conditions (or Brewtan)
  (my working hypothesis is that SMB is better but I do not have any evidence to prove it)

• these are not simple experiments

• if I were to suggest a path, it would be to do rigorous taste tests of the final beer (it is too complicated otherwise)

• the message for homebrewers is to not put all their chips on SMB (yet)

[system]

@lupulus

I appreciate that Bryan (@Beerery) is trying to simplify the discussion, but in doing so we may be simplifying too much and making too many assumptions.

START OF CHEMISTRY BRIEF
Here some statements that the group should feel free to correct/ improve

• Oxidation-reduction reactions are within the realm of what some have called RedOx chemistry. Here are
  some definitions:

• oxidation is loss of e−
• reduction is gain of e−
• oxidizing agent gains e− during reaction and is therefore reduced during reaction
• reducing agent loses e− during reaction and is therefore oxidized during reaction
• oxidized form form of molecule relatively lacking an e−
• reduced form form of the molecule relatively having an additional e−
  A molecule with a higher negative redox potential than another molecule will tend to lose electrons (i.e. to be oxidized by reducing another molecule, eg. a free radical) more than a molecule with a lower negative redox potential; and a molecule with a higher positive redox potential will tend to gain electrons (i.e. to be reduced by oxidizing another molecule).
  These reactions are of course dependent on the concentration of the reacting molecules, concentration of other molecules that can reduce/oxidize, the pH of the solution, and the temperature of the solution
  END OF CHEMISTRY BRIEF

We do not know whether the redox potential of SMB in mash conditions is higher than that of ascorbic acid (it would be my working hypothesis that SMB is a better antioxidant but again, there is no data in our experimental conditions). Remember that SMB will be mostly in the sulfite form under mash conditions, so we cannot use data collected when it was mostly in the sulfite form (at higher pH).
I also agree it is a fair working hypothesis that dehydroascorbic acid (oxidized ascorbic acid) is more prone to regain the lost electron by oxidizing another molecule vs oxidized bisulfite; but again, this is not proven either. It may even be different for L- vs D-ascorbic acid.
If you add gallotanins (Brewtan) to the equation, it will get even more complicated

Bottom line

• it is not proven that mole to mole, SMB is better than ascorbic acid in mash conditions (or Brewtan)
  (my working hypothesis is that SMB is better but I do not have any evidence to prove it)

• these are not simple experiments

• if I were to suggest a path, it would be to do rigorous taste tests of the final beer (it is too complicated otherwise)

• the message for homebrewers is to not put all their chips on SMB (yet)

Oh come on, was it my bouncer at the door that was too broad!?!?  ;D ;D

As always thanks for the reply. I should have a permanent preface, that these are my findings.

[macbrews]

What would one expect the DO of a glass of German pils to be?
Just got a meter and it read around .5 ppm on a beer I made with Brewtan.