Using H2O2 to oxigenate

Physics, chemistry and biology of brewing. The causes and the effects.

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mikey2
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Using H2O2 to oxigenate

Post by mikey2 »

Has anyone ever tried using Hydrogen Peroxide to oxigenate the wort instead of shaking the carboy, or using pure oxygen and a S.S air stone ? I don't mean using the common 3% Peroxide that you buy in a drug store (which has added chemical stabilizer), but I mean pure 35% food grade (or higher) Hydrogen Peroxide which can be bought in a health food store. I have tried this with success by adding 10 drops to the 5 G. wort about 10 Min before the yeast, fermentation started as quickly as when I use O2 and the S.S. airstone. Any comments? Mikey
jayhawk
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pH

Post by jayhawk »

From what I remember from high school, it would seem that the addition of H202 would change the ph of your beer (do you agree?) Could this have an affect on flavour, as well as on yeast viability over the course of the ferment?
mikey2
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O2 vs pH

Post by mikey2 »

I have not taken pH measurements after using H2O2, but the flavor was not adversly affected. Since H2O2 is simply a water molecule with an extra oxygen atom, my theory is that this would release the oxygen into solution. As I mentioned, I have tried this on a few batch's and have had good results, but I don't know the exact scientific explanation for how it works or why it works, but I'm open to hear from anyone who can provide it. If this really is a good way to oxigenate, it is very simple and low cost, as 35% H2O2 only cost about $10 per pint, and at only 10 drops per batch, it would go a long way. I'm not even sure that 10 drops is the correct amount to use, but this is the amount that I used which seemed to work well. Are there any chemist types out there that can explain the H2O2 reaction and why (or why not), this works ?
BillyBock
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Interesting.....Mesa Any Thoughts?

Post by BillyBock »

I find this concept intriguing. I wonder what Mesa has to say on the chemistry aspect of it? It'd make oxygenating simple for sure.
jayhawk
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H202 healthy?

Post by jayhawk »

I just "googled" H202 and apparently some people swear by it for general health maintenance. They claim that it is healthy because of its ability to provide high amounts of oxygen to the body. From this info, I don't see how adding it to beer would be harmful. This idea is very intriguing.
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Mesa Maltworks
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Uhhh...

Post by Mesa Maltworks »

Well, I researched this through the ASBC (American Society of Brewing Chemists) and this agent is not on the approved list for use in beer. Why, I do not know, but if it is a cheap and easy substitute for using oxygen (sterile filtered air is the cheapest) why is it not commercially used? With the amount of long term technical research that has taken place in the brewing industry to reduce lag times, I can only conclude there is some sort of negative associated with it's use. It may only be cost but it could also be yeast health affects or something else microbiologically detrimental.

Since this actually did not answer the question, I have e-mailed this to a brewing scientist friend in Lexington, KY who will surely know and I will post his reply.

Eric
canman
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no expert

Post by canman »

Not by any means but if I remember correctly this is a very stable compound that will not freely give up its bonds. Therefore the O2 in the H2O2 will remain bonded to the H2 and not be released for use by other interlopers like yeasty beasties. I could be wrong but i think it will be the first tme ever:)
jtvd
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H2O2 stability and pH

Post by jtvd »

Hydrogen peroxide is very unstable. At higher concentrations it was used to fuel the one-man rocket pack developed by the US Army in the 1950's.
At 35% concentration it is a strong oxidizer. I once used very small amounts (100 ml in 1800 gal with a BOD of 500mg/l) to decrease BOD in Wastewater. In fact, there was an excess of oxygen
jayhawk
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Ph cont'd

Post by jayhawk »

Adding H202 is not "adding oxygen". Since H202 is both 02 and H2, you are adding H ions as well as 02 ions. From what I recall, I think H rarely hangs out in the H2 form. In fact, I think H2 is called "helium". Therefore, H202 would dissociate in liquid into 2 Hs and one 02, thereby adding H ions, which would affect the pH of the liquid. I am not sure if it would increase or decrease the pH.
jtvd
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H2O2

Post by jtvd »

The chemistry get more complex with hydrogen peroxide. H2O2 is water with an extra oxygen molecule attached. Water has a covalent bond which is very stable under most conditions. Thus water is often expressed in chemistry as HOH which gives a clearer picture of the nature of the molecule. The hydrogen does not dissociate from the oxygen and form H2 or hydrogen gas. But there is an H ion and an OH (hydroxyl) ion that are tightly bonded. The H ion (hydrion) tends to lower pH and the OH (hydroxyl) ion tends to increase the pH. In solution, there are HOH molecules and unstable Oxygen atoms. The unstable Oxygen atoms combine to form O2 (oxygen gas) and outgas, leaving water with a pH of 7.00.
Peroxide will not affect the pH of the beer. It will provide large quantities of oxygen--thus its classification as a strong oxidizer. It can destroy metals and soft tissue very quickly.
Many of the people posting here have access to a couple types of common lab equipment - pH meters and DO (Dissolved Oxygen) meters. A very quick test of pH and DO will show the effect of peroxide on beer or any other solution.
I would like to try the peroxide addition at very low dose to a batch of beer. I think I would dilute 1 ml 35% H2O2 to 100 ml with deionized water and add just a few ml to 5 gallons of beer. As I said before, it is impressive how little 35% peroxide provided an excess of oxygen in 1800 gallons of wastewater with a high BOD.
Has anyone discussed just how much oxygen you really want in 5 gallons of wort for optimum yeast growth? Knowing this would make the peroxide dosage very simple.
il0vepez

H2O2

Post by il0vepez »

We used H2O2 in our lab to strip cellular proteins of their metal ions. I found that H2O2 was toxic to most Eukaryotic cells (yeast not tested) between 0.1% and 0.01%. My calculations show that you are well outside that range, which is why you have beer. The chemistry of peroxides is grossly incorrect as to what I've read thus far on this page. A more descriptive form HOOH, undergoes hydrolysis (splitting by water) to form radical species in solution, OH. However, this species is uncharged and thus will not affect your pH. At this point though, you have radicals floating around inside your yeasties. Although they may be using lots of energy, (hence the CO2 respired), much of this will be going to repair themselves instead of making more yeast. I would argue that adding HOOH to your wort is highly counter productive. This is why I suspect that no commercial brewers use peroxides, aside from the fact that the FDA probably wouldn't like HOOH on the ingredient list.
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