Hydrogen Peroxide for Aeration

mattd2 said:

Why would it kill the yeast? The only information I have got from this thread from others is they have suggested that it will kill the yeast because H2O2 is a sanitiser. Yes it is a sanitiser, when mixed at the proper concentration for sanitising. What is doing the sanitising is the O2, therefore if you claim that trying to use H2O2 to oxygenate will kill the yeast, then I could claim that using oxygen to oxygenate will kill the yeast (if you get enough of it in there somehow )
No one has given any real evidence that H2O2 used at the proper concentration for oxygenation will kill the yeast. Pollox has given anecdotal evidence that it could actually work and did not reasult in off flavours, but no one has come back with concrete evidence why (or why not) this would work.

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using oxygen to oxygenate actually will kill the yeast- in concentrations over ~40ppm. (so says wyeast.com) that is .004%. same as concentrated oxygen will destroy many materials (not only organic, also metals, plastics, minerals...).

hydrogen peroxide is an effective disinfectant even in concentrations down to somthing like 0.02 to 0.05%. adding a 3% or 5% soloution to almost anything living will kill it.

i would not be adding it into the beer though. you would likely kill your yeast, as others have suggested.

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was the short form of me saying "i doubt anyone trying to do this would actually calculate out the oxygen content and use the correct concentration. people are most likely to overestimate by many orders of magnitude and end up killing their yeast."

i would think that, yes, you could probably get the ratio correct and use it for oxygenating your wort- IF (big if) you could know how hydrogen peroxide would react with the assortment of different chemicals in the wort (as its not directly free oxygen, it needs to be converted into oxygen by some process). who knows what effect a powerful oxidizer would have on alpha acid, or the starches and proteins. who knows how much of the oxygen content of H2O2 gets converted into free oxygen.

Hydrogen peroxide is NOT an antibacterial and shouldn't be used to clean wounds

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it only shouldnt be used due to the fact that it destroys good cells as well as bad cells. it is still a potent antimicrobial agent, and will destroy bacteria, fungi, and other living things. topically, its not effective to treat bacterial infection because of the bodily process involved in an infection (puss and mucous dillute the peroxide or sequester the bacteria enough to reduce its effectiveness at destroying them).

Good discussion on the topic with citations...

http://hbd.org/discus/messages/26895/29408.html?1112143606

aomagman78 said:

That's a good plan mattd2. I gotta say though, I've started venturi-ing as I transfer and have seen a huge improvement. I think this is probably a better/more reliable method for aerating the wort. But to each his own. I have heard between 8-16ppm O2 is the correct amount, yes? A simple mole balance, with some consideration for lack of efficiency to O2 would be useful. Also, making an 'O2 starter' separate with tap water could be useful, then adding - because the process/equilibrium for decomp is reduced in acidic environment. So your pH ~7 tap water may be more effective.

Hope there are no ruined batches if some of my logic is wrong.

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I am getting a bit swayed to the "do not do" side after I read that H2O2 is used to decrease the BOD/COD in wastewater. (As I undetsand Biological Oxygen Demand) wort would have a huge BOD (it is basically food that organisms will use to convert, with oxygen, into energy), so that would mean that the H2O2 might be using up yeast food instead of providing oxygen. I am still keen to to a side by side, maybe a 6 gallon batch split 3 ways - control, H2O2, aerate as well as I can.

audger said:

using oxygen to oxygenate actually will kill the yeast- in concentrations over ~40ppm. (so says wyeast.com) that is .004%. same as concentrated oxygen will destroy many materials (not only organic, also metals, plastics, minerals...).

hydrogen peroxide is an effective disinfectant even in concentrations down to somthing like 0.02 to 0.05%. adding a 3% or 5% soloution to almost anything living will kill it.

...

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That is what I said, it is a sanitiser when mixed in the right concentration (over 40 ppm of oxygen as you have said). I said it would not be a sanitiser if mixed at the correct dosage to give ~8 - 10 ppm oxygen in the wort. i agree that you won't actually know exactly what it is doing in there without some chemstry eveluation but at the very least it should not kill yeast at low levels.

I compare it with starsan, we all know starsan is a sanitiser, and we all know not to rinse it after use because once diluted down by the wort it no longer sanitises as the concentration is to low.

OK, 3rd post in a row
Just had the thought: the most common compond in wort (after water) is maltose - C12H22O11, sugar reacts with H2O2 like so (from yahoo answers so don't trust it 100%).
C12H22O11 + 24 H2O2 = 12 CO2 + 35 H2O
I don't know what reation would be more prominate but at least some of your hard work to extract sugars would be wasted duue to the H2O2 breaking them down into water and carbon dioxide
I guess this supports my last post on decreasing the BOD of the wort (not something you want to do in our case)

Ya, I guess I was thinking about it more from a pure water standpoint. So after reading some of that stuff I would probably only use it outside the wort. Probably the best way would be to mix up a 1L bottle (pepsi, coke, whatever) with tap water and the proper concentration of H2O2. Seal that, shake, let it sit for couple hours in sunlight and such, then chill overnight. That might give you a highly oxygenated liquid that you could mix into your wort once cooled. But I don't know.

And venturi-ing is where you rack your wort from your kettle to your fermenter (after cooled) using your autosiphon. But along the path of the hose you reduce the diameter with a second hose. At that junction you place a pin hole in the smaller diameter hose. The acceleration of the liquid due to the reduced diameter will suck in air. And some of this air will become dissolved along the rest of the hose path. Here is a thread on it.
https://www.homebrewtalk.com/f51/cheap-easy-aeration-gadget-68218/

aomagman78 said:

Ya, I guess I was thinking about it more from a pure water standpoint. So after reading some of that stuff I would probably only use it outside the wort. Probably the best way would be to mix up a 1L bottle (pepsi, coke, whatever) with tap water and the proper concentration of H2O2. Seal that, shake, let it sit for couple hours in sunlight and such, then chill overnight. That might give you a highly oxygenated liquid that you could mix into your wort once cooled. But I don't know.

And venturi-ing is where you rack your wort from your kettle to your fermenter (after cooled) using your autosiphon. But along the path of the hose you reduce the diameter with a second hose. At that junction you place a pin hole in the smaller diameter hose. The acceleration of the liquid due to the reduced diameter will suck in air. And some of this air will become dissolved along the rest of the hose path. Here is a thread on it.
https://www.homebrewtalk.com/f51/cheap-easy-aeration-gadget-68218/

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That is not a bad idea aomagman, and at the levels you would need for oxygenation of a full batch of wort the ~1L should be high enough concentration of oxygen to be santise/sterile(?). I was almost giving up on this, but you have renewed my drive!
New plan: Make wort (asssume ~0 ppm oxygen after the boil), transfer with as little splashing as possible to "high" oxygen water. ferment

The venturi is a good easy idea but I would be worried making sure it was clean air getting in. And from the photos in the thread you linked I am wondering if the ones that people have at then end of the racking tube are actually doing much. I would have thought you need to have the venturi as close to the kettle as possible to get the most venturi effect.

Hey I'm a chemist.

H2O2 for aeration is a stupid idea.

Thanks for the help insub
Being that you are a chemist you should be able to actually tell us why it is so stupid?

Also can you tell me how to tell what reaction will take precidence, i.e. for this example either the water + H2O2 or the sugar + H2O2 (i am assuming that any disolved metals/salts will be minimal so will make up a small percentage of the overall reactions and they could be ignored). I am guesing it will be the sugar + H2O2, but would like to know how to tell for the future.

Also can you confirm I have the sugar + H2O2 equation correct (the actual yahoo answers had sugar as C12H24O11, maltitol, but that left a couple of hydrogens not doing anything afterwards)

mattd2 said:

Thanks for the help insub
Being that you are a chemist you should be able to actually tell us why it is so stupid?

Also can you tell me how to tell what reaction will take precidence, i.e. for this example either the water + H2O2 or the sugar + H2O2 (i am assuming that any disolved metals/salts will be minimal so will make up a small percentage of the overall reactions and they could be ignored). I am guesing it will be the sugar + H2O2, but would like to know how to tell for the future.

Also can you confirm I have the sugar + H2O2 equation correct (the actual yahoo answers had sugar as C12H24O11, maltitol, but that left a couple of hydrogens not doing anything afterwards)

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A bio-organic-analytical nobel prize-winning chemist couldn't tell you all the specific reactions that would be happening. The wort is very complex, and the entire point of brewing is to control as much of the process as humanly possible.

1. At low concentrations, H2O2 is still H2O2 and will be involved in the same types of reactions - which have been shown to stress/kill yeast and other single-celled organisms.

2. When we try to calculate precise volumes, gravity, IBU, etc...and then you want to dilute the wort with a strong oxidizer thereby changing concentrations via dilution and chemical reactions?

3. H2O2 is known to react with carboxylic acids forming peroxy acid which can react with alkenes, amines, thioesters, on and on (by the way, every amino acid is a carboxylic acid and amino acids are the building blocks of proteins)

So what are you really doing chemically to the wort? Your guess is as good as mine, but it isn't as simple as a reaction with "water" or "sugar". Which sugar? How many different sugars do you have?

You're not just getting oxygen, you are getting a lot of byproducts which will vary depending on the amount of H2O2, the type of grain, the reaction volume, etc.

Get my point...should I go on?

It's stupid. Keep it simple(r).

mattd2 said:

Wow this Dr Fix seems a bit loose, and the BT guy as well. The artical doens't even state how much H2O2 was used in "Dr" Fix's trial

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Yes, Doctor Fix. George Fix had a doctorate from Harvard and, more importantly, has probably contributed more to the science of homebrewing than any other single individual. A second hand account of one experiment shouldn't dissuade you from trying new things, but nor should it activate your snark-organ. Lose the scare-quotes and learn to respect your betters, kiddo.

I jumped into this topic late, but I want to input my biology background into this mess. Hydrogen peroxide(H2O2) is one of many molecules known as 'Reactive Oxidative Species' or ROS( http://en.wikipedia.org/wiki/Reactive_oxygen_species ). ROS's highly reactive and tend to cause problems for most living organisms. ROS's are highly reactive to many of the molecules within the cell that includes DNA, RNA, proteins, and many others( http://www.ncbi.nlm.nih.gov/pubmed/18708137 ). Most organisms have a defensive mechanism in the form of proteins that deal with ROS's by catalyzing them into less reactive molecules that are less damaging to the organism.

The issue I see with this is that with the increased ROS's, in the form of H2O2, has the possibility of damaging genes integral the fermentation process and incite increased stress response in the yeast. The stress response comes in the form of activating genes, producing proteins, and catalyzing the ROS all of which requires energy. The yeast will live through low concentrations of H2O2, but will likely activate a stress response pathway in order to deal with it. The problem with this is it requires extra energy from the yeast to facilitate the stress response pathway in order to rid the environment of H2O2. In the case of making beer yeast derive their energy by fermentation of sugar to ethanol, an already inefficient process, which will be made even less efficient if the yeast have to divert that energy to deal with the H2O2 presence. Also there has been studies on the correlation between cell induced death, apoptosis, when in the presence ROS's( http://www.ncbi.nlm.nih.gov/pubmed/18298957 )

Furthermore if you're an individual who likes to re-use your yeast, I personally wouldn't reuse yeast from a batch that has had H2O2 in it because of the risk of mutations to genes that are important for yeast reproduction and ethanol fermentation. There is not sure way to know if a mutation resulting from the presence of an ROS has occurred, but there is always the risk. You want your yeast as healthy and 'happy' as possible.

There is a ton more we could go into, but I think you're better off finding other ways to aerate your wort than by using an ROS such as hydrogen peroxide.

insubordinateK said:

A bio-organic-analytical nobel prize-winning chemist couldn't tell you all the specific reactions that would be happening. The wort is very complex, and the entire point of brewing is to control as much of the process as humanly possible.

1. At low concentrations, H2O2 is still H2O2 and will be involved in the same types of reactions - which have been shown to stress/kill yeast and other single-celled organisms.

2. When we try to calculate precise volumes, gravity, IBU, etc...and then you want to dilute the wort with a strong oxidizer thereby changing concentrations via dilution and chemical reactions?

3. H2O2 is known to react with carboxylic acids forming peroxy acid which can react with alkenes, amines, thioesters, on and on (by the way, every amino acid is a carboxylic acid and amino acids are the building blocks of proteins)

So what are you really doing chemically to the wort? Your guess is as good as mine, but it isn't as simple as a reaction with "water" or "sugar". Which sugar? How many different sugars do you have?

You're not just getting oxygen, you are getting a lot of byproducts which will vary depending on the amount of H2O2, the type of grain, the reaction volume, etc.

Get my point...should I go on?

It's stupid. Keep it simple(r).

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Fair enough that it would be near impossible to determine what is actually happening in the wort. And I had already concluded that adding the H2O2 to the wort was not a good idea, but I was just assuming that because there are a lot of other reaction that could (and probably would) take place instead of the decomposition of H2O2. Sugar + H2O2 being was what I guessed (since I am not a chemist) to be a major one. Given that the low likelihood of H2O2decomposing occurring, there is a low likelihood of O2 being released into the wort and if this doesn't happen then there is no point in adding the hydrogen peroxide in the first place. It would have been helpful to have a brief summary of what you just said in you first post, thanks for the additional information.

MalFet said:

Yes, Doctor Fix. George Fix had a doctorate from Harvard and, more importantly, has probably contributed more to the science of homebrewing than any other single individual. A second hand account of one experiment shouldn't dissuade you from trying new things, but nor should it activate your snark-organ. Lose the scare-quotes and learn to respect your betters, kiddo.

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Yes, I might of misinterpreted the second hand account (and the only account of it I can find) of the experiment . But also that account and the one from pollox don't match up. I would have to guess this was possibly because Pollox added a smaller amount and waited before adding the yeast.
Yes I had no idea who Dr George Fix was before this thread, now I do after searching for him due to your post. I don't see the point of your last comment though. Yes I shouldn't use quotes around the Dr because he does in fact have a PhD in mathematics, but his (again from the only second hand account of the experiment) if the person quoting him states that they did not see the point of calculating what concentration of H2O2 to use Either they did not do enough reading or it was not determined in the first place and an arbitory (and probably excessive) amount was used. I don't see how he is better than me because he has contributed more to the homebrewing community, yes he might of known (and probably did) more than me in regards to homebrewing but I fail to see how that makes him better. And what's with the kiddo? I am 26, married with 3 kids, finished university and working as a professional engineer for the last 5 years, and only I'm 4 years younger than you - kiddo, really? Of course I apologise for ranting on that if the was meant to make that pretty offensive comment a joke.

did that once and lost 2 liters of wort if you want to use peroxide you can put it in a separate jar and use the silicon cork from airlock and some tubing mix the hydrogen peroxyde with potassium iodide in the jar and bubble the gas into the wort