Hot Side Aereation references

[Lupulus]

First, your literature search should be focused on flavor stability + oxidation. Hot Side Aereation is rarely mentioned as such in the literature.
Brewing textbooks: it's profusely mentioned in the two major Brewing Science books, Narziss and Kunze.
Manufacturing: All major manufacturers design their equipment for inert brewing, aka LODO.
Brewing schools: Weihenstephan, VLB, Siebel train brewing engineers to brew LODO, using the textbooks mentioned and related literature.
All pale lagers made by major breweries are made this way.
Papers are published in all major brewing journals. Yes, takes time to find them.
Does it make better beer? They do think so, clearly, but taste is individual, so you can disagree.
Does it apply to every style? Research in other styles is limited.
LODO beers taste different. Better or worse is up to you.
But if you are cloning LODO beers, you won't clone them with a non LODO process.
Prost!

Here's an easy to follow presentation from Professor Narziss himself.
http://www.ebc-symposium.org/uploads/mycms-files/documents/2016/presentations/L1 Narziss.pdf

 

[McMullan]

But where are the data suggesting home brewers should consider HSA? If it makes a noticeable difference it must be detectable chemically, e.g. by mass spec, which has been pretty routine analysis for years. The experimental design is child's play, for goodness sake. A brewer's personal opinion, regardless who he or she is, isn't a substitute for real data. No one is questioning the impact of oxidation on the stability of commercial beer. Nor has it ever been recommended to mash and boil carelessly. It's hot and dangerous for a start. But most brewers aren't obsessed with minimising O2 on the hot side and still manage to produce great beer. I suspect LODO brewers are at a point of diminishing returns, obsessing about 'perfection'.

By the way, I have a copy of Kunze (2004). He very briefly mentions potential benefits of minimising oxidation in the mash (p.242), the hot side, but he provides no data or references to the scientific literature on the matter.

 

[Lupulus]

But where are the data suggesting home brewers should consider HSA? If it makes a noticeable difference it must be detectable chemically, e.g. by mass spec, which has been pretty routine analysis for years. The experimental design is child's play, for goodness sake. A brewer's personal opinion, regardless who he or she is, isn't a substitute for real data. No one is questioning the impact of oxidation on the stability of commercial beer. Nor has it ever been recommended to mash and boil carelessly. It's hot and dangerous for a start. But most brewers aren't obsessed with minimising O2 on the hot side and still manage to produce great beer. I suspect LODO brewers are at a point of diminishing returns, obsessing about 'perfection'.

By the way, I have a copy of Kunze (2004). He very briefly mentions potential benefits of minimising oxidation in the mash (p.242), the hot side, but he provides no data or references to the scientific literature on the matter.

1. Nobody does research for homebrewers but most all research is done in small systems, so it's more applicable to Homebrewers.
2. Kunze 2015 has much more info. Includes chemiluminescence results form the Wurzbacher 2011 dissertation
3. Square-cube law indicates the potential for oxygen ingress is 20x higher in homebrew systems.
4. The experiments in flavor stability have been done many times. The first paper I recall is Narziss 1986.
5. No manufacturer will spend 100s of millions in equipment with no data.

I am not going to engage in a back and forth.

Now that you know the data is there, please go read Kunze, read Narziss, read Back, start collecting papers, look at the data and make up your own mind.

Good luck!

 

[McMullan]

If you’re a commercial brewer who needs to maximize stability of your beer, I could understand you might pursue certain practices. If you’re a home brewer, I don’t understand the obsession with oxygen at every stage of the process. It’s currently driven by beliefs, not scientific data. It little more than a backwater in brewing science.

 

[Lupulus]

If you’re a commercial brewer who needs to maximize stability of your beer, I could understand you might pursue certain practices. If you’re a home brewer, I don’t understand the obsession with oxygen at every stage of the process. It’s currently driven by beliefs, not scientific data. It little more than a backwater in brewing science.

Wow!
You already read all the references?
There are more then 200 in the Wurzbacher dissertation alone, many related to the topic.
All research is done at a homebrew scale (who would brew 50hL of each treatment?).
No scientist does research strictly for homebrewers, so if that's your bar, you win. None of the 1000s of papers I have in brewing, has homebrewing as the audience.

 

[Bilsch]

If you’re a commercial brewer who needs to maximize stability of your beer, I could understand you might pursue certain practices. If you’re a home brewer, I don’t understand the obsession with oxygen at every stage of the process. It’s currently driven by beliefs, not scientific data. It little more than a backwater in brewing science.

And yet you were willing to try a process for doing just that based on very little evidence other than one persons belief that AA reduced oxygen and made his beers better.

Why is one theory acceptable for testing by home brewers and another, almost identical one, simply a bridge too far?

 

[Bassman2003]

If you’re a commercial brewer who needs to maximize stability of your beer, I could understand you might pursue certain practices. If you’re a home brewer, I don’t understand the obsession with oxygen at every stage of the process. It’s currently driven by beliefs, not scientific data. It little more than a backwater in brewing science.

There is a flavor component to minimizing O2 throughout the process. Those of us that have learned about how to get that flavor at the homebrew level want to keep getting it! Taste & flavor are tough to document. So, you are just going to have to try it for yourself or accept that any others do like the results. Outside of those two choices, further distance down your current path is just obstinance imho.

To use your words, if you 'do not understand' then learn or accept.

 

[McMullan]

Wow!
You already read all the references?
There are more then 200 in the Wurzbacher dissertation alone, many related to the topic.
All research is done at a homebrew scale (who would brew 50hL of each treatment?).
No scientist does research strictly for homebrewers, so if that's your bar, you win. None of the 1000s of papers I have in brewing, has homebrewing as the audience.

Given at this point you are just trolling me, I leave you to it and focus on those who really care.

200 references is a bit thin for a dissertation. Was it an MSc or a PhD? And how many actually reported data specifically on HSA? I read a blog yesterday where the authors dumped a small collection of ‘academic references’ on beer stability and oxidation, but they neglecTed to cite any for the claims published on their blog. Insufficient data for a coherent presentation, I guess. AKA, winging it, to push beliefs. You’ll note too that scientific research in brewing usually begins at bench scale (about the size of a starter) before scaling up to pilot plant. So no shortage of research relevant to home brewers, should they wish. Not quite the same as trying to scale down from a commercial brewery, a macro, to home brew, due to complicated non-linear changes well beyond simple ‘geometry‘.

 

[McMullan]

And yet you were willing to try a process for doing just that based on very little evidence other than one persons belief that AA reduced oxygen and made his beers better.

Why is one theory acceptable for testing by home brewers and another, almost identical one, simply a bridge too far?

Why not? I’m very open-minded. The lack of data is actually a completely separate matter, associated with pseudo scientists who claim HSA is an established theory accepted by a scientific consensus when, in fact, it isn’t. Again, it’s a backwater in brewing science. It’s going to take considerably more research and independent confirmation of results before anything like a scientific consensus, for or against, forms. Years! And yet here we have people expressing biased preconceived ideas and offering subjective opinions as their key evidence.

 

[Lupulus]

Straw Man Fallacy
Of the many types of logical fallacies, the straw man fallacy is particularly common in political debates and in discussions over controversial topics. The basic structure of the argument consists of Person A making a claim, Person B creating a distorted version of the claim (the “straw man”), and then Person B attacking this distorted version in order to refute Person A’s original assertion.
Often, the distorted interpretation is only remotely related to the original claim. The opposing argument may focus on just one aspect of the claim, take it out of context or exaggerate it. The straw man argument, in this way, is an example of a red herring. It’s meant to distract from the real issue being discussed and is not a logically valid argument.
The best way to understand this phenomenon is with a straw man fallacy example. Please read below then previous posts.
M: there's no literature on HSA
L: here's the literature
M: (without reading any of the literature) but it's all commercial, not homebrewing
L: Experiments are mostly done in homebrew sizes (or smaller)
M: (without reading any of the literature and without any valid response)
...but 200-300 references do not meet my arbitrary standard, and let me compare a Weihenstephan dissertation (that I didn't read) with something completely unrelated.
L: Really?! Really?!

 

[McMullan]

There is a flavor component to minimizing O2 throughout the process. Those of us that have learned about how to get that flavor at the homebrew level want to keep getting it! Taste & flavor are tough to document. So, you are just going to have to try it for yourself or accept that any others do like the results. Outside of those two choices, further distance down your current path is just obstinance imho.

To use your words, if you 'do not understand' then learn or accept.

I get plenty of pleasant flavours in my beer, thanks. Especially from those fermented in my Yorkshire square, where fermenting wort is recirculated and sprayed on top of the yeast head. The other end of the spectrum, you could say, but wonderful beer nonetheless. How on Earth is that possible?

 

[Bassman2003]

You showed your hand a bit... We are not talking about your beer. Defensiveness is not a good look for anybody. As I stated before, please refrain from turning informative posts into arguments by not wanting to learn or accept. If I can speak for others as well as myself, please do not post on these topics if you do not have anything constructive to say. We have all heard your arguments before. There are others here who probably want to learn about these complex topics and getting the threads shut down it just plain wrong.

After all, this is the LODO forum. Why not stay out of the forum if you do not agree with the practice?

 

[McMullan]

Straw Man Fallacy
Of the many types of logical fallacies, the straw man fallacy is particularly common in political debates and in discussions over controversial topics. The basic structure of the argument consists of Person A making a claim, Person B creating a distorted version of the claim (the “straw man”), and then Person B attacking this distorted version in order to refute Person A’s original assertion.
Often, the distorted interpretation is only remotely related to the original claim. The opposing argument may focus on just one aspect of the claim, take it out of context or exaggerate it. The straw man argument, in this way, is an example of a red herring. It’s meant to distract from the real issue being discussed and is not a logically valid argument.
The best way to understand this phenomenon is with a straw man fallacy example. Please read below then previous posts.
M: there's no literature on HSA
L: here's the literature
M: (without reading any of the literature) but it's all commercial, not homebrewing
L: Experiments are mostly done in homebrew sizes (or smaller)
M: (without reading any of the literature and without any valid response)
...but 200-300 references do not meet my arbitrary standard, and let me compare a Weihenstephan dissertation (that I didn't read) with something completely unrelated.
L: Really?! Really?!

Again, if you’re a commercial brewery concerned about the stability of your product you might want to adopt certain practices to promote stability of your product. If you’re a home brewer and you believe such practices are worthwhile that’s your choice. Just stop pretending it’s an established theory. HSA is a largely untested hypothesis. You can’t just cherry-pick opinions that agree with it. Are you suggesting beers produced without attempts to limit aeration during mashing are not as good or inferior?

 

[McMullan]

You showed your hand a bit... We are not talking about your beer. Defensiveness is not a good look for anybody. As I stated before, please refrain from turning informative posts into arguments by not wanting to learn or accept. If I can speak for others as well as myself, please do not post on these topics if you do not have anything constructive to say. We have all heard your arguments before. There are others here who probably want to learn about these complex topics and getting the threads shut down it just plain wrong.

After all, this is the LODO forum. Why not stay out of the forum if you do not agree with the practice?

It’s not so much that I disagree, it’s the lack of data that means we’re unable to accept or reject the theory with any confidence. The problem is with believers pretending the theory is established ‘fact’. It’s bordering on spreading misinformation, due to bias and naive interpretation of literature that’s mainly not about HSA.

 

[Bilsch]

Vale.. is that you my friend?

 

[Lupulus]

Vale.. is that you my friend?

Is s/he the same one that was asking: Where are the references?
Is s/he implying that he read the literature?
Did he read the Narziss paper?
No
The Wurzbacher dissertation?
No
Kunze?
No
Narziss?
No
...
But s/he wants more references he's not going to read?

 

[Bassman2003]

It’s not so much that I disagree, it’s the lack of data that means we’re unable to accept or reject the theory with any confidence. The problem is with believers pretending the theory is established ‘fact’. It’s bordering on spreading misinformation, due to bias and naive interpretation of literature that’s mainly not about HSA.

I respect your's and anyone else's right to their own opinion, bias, process goals etc... How about you respect others' opportunity to discuss such matters instead of blowing up every thread? Just do not post if you do not like the approach. The entire forum knows how you feel about the topic by now... And please keep the "save the others' from disinformation crusade" in reserve. That is a little bit over the top should it arise. Thanks for your cooperation!

 

[hopjuice_71]

Hot side aeration (HSA) is some weird term coined by I don't know who. It doesn't really mean a whole lot - aeration is the dissolution of the components of air into a liquid, it doesn't reflect the important (bio)chemical reactions that may arise. If you want to learn about oxidation on the hot side of brewing you have to search (on Google Scholar for example) "brewing oxidation" or "brewing oxidation mash" (etc). There are a ton of references - I know this is what the thread is about but there are too many to sort through. They include everything from subjective assessments (I view tasting panels as subjective) to objective measurements, such as by nuclear magnetic resonance spectroscopy (hard to question the detection of oxidized metals). Oxidation clearly happens on the hot side, which is why I went down the rabbit hole a few years ago. Long story short, what I question is the whether the measures to mitigate oxidation on the hot side to preserve (subtle) flavour aspects, aesethics (lighter color), or (long term) storage properties are really of concern to everyone (the latter being key). It seems to be quite a personal preference. Personally, I didn't need the stability gains (I'm not a commercial brewer, I store my beer cold once fermentation is done, and it is gone within a couple of months) and I didn't really appreciate the flavours...or they were swamped out by my love of hops I started viewing LODO/LOB as a real science-supported issue, but just yet another a knob to be twiddled depending on what your brewing goals are. My feeling is that there is now, and will be forever more, two camps and and a continuum in-between regarding this issue. And yes, I am Canadian, eh, so I am sorry for my fence-sitting

 

[Bilsch]

I started viewing LODO/LOB as a real science-supported issue, but just yet another a knob to be twiddled depending on what your brewing goals are. My feeling is that there is now, and will be forever more, two camps and and a continuum in-between regarding this issue. And yes, I am Canadian, eh, so I am sorry for my fence-sitting

I think every low oxygen brewer would agree with your assessment that it's just another lever you can pull and we advocate for simply that. However I don't believe it will continue as two opposing camps because that paradigm is fading every year. Eventually people will forget why this silly division started in the first place and lodo will be just another wrench in the brewing toolbox as it should be. Nothing more, nothing less.

 

[McMullan]

Is s/he the same one that was asking: Where are the references?
Is s/he implying that he read the literature?
Did he read the Narziss paper?
No
The Wurzbacher dissertation?
No
Kunze?
No
Narziss?
No
...
But s/he wants more references he's not going to read?

Your sources are actually very limited and (therefore) potentially suffering from predictable bias. The data lacking so desperately is independent confirmation of what some propose re oxidation due to aeration during mashing. Joe Blogs and his mate can repeat their claims over and over, it's not a substitute for independent confirmation of the claims. AKA the scientific method. So where are these peer reviewed independent confirmations aeration during mashing matters and why, under which circumstances, should brewers, including home brewers, care? We need more data, not enthusiastic opinions from believers on the fringe.

 

[McMullan]

I respect your's and anyone else's right to their own opinion, bias, process goals etc... How about you respect others' opportunity to discuss such matters instead of blowing up every thread? Just do not post if you do not like the approach. The entire forum knows how you feel about the topic by now... And please keep the "save the others' from disinformation crusade" in reserve. That is a little bit over the top should it arise. Thanks for your cooperation!

I actually typed 'misinformation'. You might want to look up the phrase and its meaning, to distinguish it from the phrase 'disinformation'. Note too I'm not the one proposing anything controversial here, in terms of novel practices for home brewers, on a home brew forum. Thanks for your output.

 

[McMullan]

I think every low oxygen brewer would agree with your assessment that it's just another lever you can pull and we advocate for simply that. However I don't believe it will continue as two opposing camps because that paradigm is fading every year. Eventually people will forget why this silly division started in the first place and lodo will be just another wrench in the brewing toolbox as it should be. Nothing more, nothing less.

But what you're advocating (via a blog with a Patreon button ) is that home brewers, in terms of effort and cost, aim to hit diminishing returns. A simple cost-benefit analysis is going to flag this up. Any effect from aeration during a standard mash procedure is going to be small compared with the brewing process overall; and not forgetting the key ingredients, malted barley, hops and yeast, which, as biological systems, come with a legacy, in the case of malted barley and hops, or active turnover, in the case of yeast, of essential endogenous oxidant loads Again, if you are a commercial brewery and you need to maximise stability of your packaged beer, you might want to adopt practices (within your budget) to minimise aeration during your mashing procedure. But is it really worth the effort and extra cost for the home brewer? I very much doubt it. No one ever recommended sticking an aeration wand into the mash. The claim there are two opposing camps here is a fake, engineered dichotomy. We're all low oxygen brewers, in reality. We all know where it's beneficial to promote aeration. What we have here is a minority obsessing over a little hot air during the mash. Don't get me wrong, I'm more than happy to experiment with adding a little ascorbic acid (additional to that naturally derived from malted barley, hops and yeast) to the mix. It requires no effort and the cost is minimal, so even the smallest perceived benefit is pretty easy to justify. Teaspoon. Plop! Done.

 

[madscientist451]

1. Nobody does research for homebrewers but most all research is done in small systems, so it's more applicable to Homebrewers.

3. Square-cube law indicates the potential for oxygen ingress is 20x higher in homebrew systems.


I am not going to engage in a back and forth.

Ok, how about a sided by side or triangle taste test comparing a LODO method beer with the same beer using "regular" homebrew methods with a knowledgeable panel of tasters?
Brulosophy did one a while back, have there been others?
You'd probably get invited to give a presentation at AHA if you could put this together in a proper way.

EDIT:
For those that haven't seen it, the AHA has provided an on line explanation of a HSA experiment:
https://www.homebrewersassociation....e Aeration of Wort, Mash and Sparge Water.pdfFrom the conclusions at the end: (these are just a portion of the conclusions)
"Does HSA occur in the 4 distinct tests? All of the beers, experimental batches and controls, presented staling characteristics. There was no definitive, overwhelming, smoking gun, data point that clearly pointed to HSA staling levels of intensity greater in the test beers versus the control batches.
The two most potentially significant observations from this experiment are:
1) the correlation of increased sweetness and fruit esters in the O2 preboil and Aerated Sparge tests, which suggests that similar oxidized reactions might be occurring in both O2 infusions.
2) The significant lower ester values and more assertive hop bitterness noted in the Postboil O2 infusion. Additional testing would be required to replicate and validate these two observations.
Implications:
The implications of the first observation, if validated thru additional testing, would mean that all grain brewers should exercise caution to avoid excessive aeration of both the sparge water, and the hot wort as it is being transferred to the Boil kettle. "

 

[DuncB]

Crikey this is a feisty thread, I'm on tenterhooks waiting for the next episode.

It's a bit Orwellian 1984 really, " 4 legs good 2 legs better"
Both will get you around but it depends on which footing you view or mobilise from.

 

[Bassman2003]

Gosh, it never seems to end... I just did a personal comparison video and the taste difference was very obvious. One may have liked the HIDO beer better, but the difference did not need a triangle test to discern. All this defensiveness is unwarranted. The LODO process removes the inherent oxidation flavors that all homebrewers have become accustomed to tasting. Naysayers and flaming arrow shooters just need to CALM DOWN. Nobody is telling you NOT to brew a certain way. Just offering a tool to put in your toolbox.

Unless you try and do the process successfully, you really do not have any basis to form an opinion do you?

Yes, flavor is subjective. We are all excited about how much better our beers are tasting and want to spread the word. Yet all of these arguments keep cropping up. Why?

 

[Miraculix]

Imagine how funny it would be if at the end of the day it turns out that throwing in a tablespoon of vitamin c pre-mash has the same effect as all the combined lodo mambo jambo that has been created by enthusiastic brewers that read somewhere that vitamin c is a "superoxidiser" and therefore ditched the idea of using it.

 

[McMullan]

One may have liked the HIDO beer better, but the difference did not need a triangle test to discern. All this defensiveness is unwarranted. The LODO process removes the inherent oxidation flavors that all homebrewers have become accustomed to tasting.

You should read that back to yourself. Honestly.

Do you mean 'the LODO process removes the inherent flavors that all beer drinkers have become accustomed to tasting'? If so, you might be onto something, finally.

 

[Bassman2003]

AA used to be part of the mix but have moved to just using sulfites. We have told you this before...

 

[Miraculix]

AA used to be part of the mix but have moved to just using sulfites. We have told you this before...

Yes, exactly, that is what I said. That is what I am referring to with "...ditched the idea of using it.".

 

[Bassman2003]

Why is that funny? Either way is an attempt to limit oxidative reactions.