Get into O2 guys, if you're serious about nicer beer

[Jack of all biers]

Wort is down and cooling in the cubes. I went with No-chill, as I ran out of time and... well.... I didn't want to be up to midnight cleaning my equipment. Again!! I will cool to fermenting temps tomorrow, while I'm at work and in the evening give the H2O2 experiment a go. I wasn't able to get the 6% solution as they were out of stock, but I got 3% Gold Cross, so will give it a crack with that. Full recipe and method to follow, when some preliminary results are in. Till then...

 

[technobabble66]

Fwiw, just posted this in another thread on oxygenation.
It's an O2 test kit for aquariums, ~$28. range is ~2-8ppm.
Not sure if it'll suit what we need, but thought i'd mention it.

 

[Jack of all biers]

Okay, so preliminary results are in for H2O2 v Aeration (standard shake till you can shake no more) comparison experiment in temp controlled conditions at full batch volume.

The fermentation is almost complete (in yeast clean up mode now) and I will say the comparison experiment is a success, as it has achieved one result for a hypothesis I was looking to test. In short I can say that I don't believe that H2O2 adds a benefit to fermentation in the same way as O2 is reported to do.* The fermentation was NOT quicker than standard shaking aeration. It was NOT more complete with better attenuation and quicker brightening (clearing). The H2O2 batch did not do terribly, but it was by no means better than standard aeration. In fact H2O2 achieved just under in attenuation (72% v 78% so far at day 9) and produced more esters at the same temperature.

I've attached my full recipe notes below,** but have summarised some of what I think are the key points here.

• Brews fermented with exact same yeast manufactured on exact same date bought cold and stored cold. Yeast calculators showed the viability to be 66% on the day of pitching but I think that is a massively conservative number (read - bunch of rubbish) as the results indicate otherwise so far.
• H2O2 batch was 1 litre more than Aerated batch.
• H2O2 batch had no splashing of any kind to minimise any variable of added O2 by other means. Aerated batch was splashed and shaken till I could do no more (3 min shake, I know I'm pathetically out of shape :unsure:
• Temp control probe attached to outside wall of H2O2 fermenter, meaning the Aerated batch could have been a bee's appendage higher or lower, but not much of a variable.
• Both fermentations appeared to begin around the same time (first noticed activity in both at 19 hours post pitch) and both appeared to behave the same up until first gravity reading (5 days).
• At 5 days, the H2O2 batch had much more yeast in suspension and was 2 gravity points higher than the Aerated batch. The H2O2 batch had much stronger flavours and aromas that the Aerated batch, which together with the very cloudy suspended yeast appearance and the slightly higher gravity is likely an indicator of yeast stress. The H2O2 batch sample had a very dry to puckering after taste that I thought did not bode well for it.
• At 9 days, the H2O2 batch had the same amount of very cloudy yeast in suspension, and was 3 gravity points higher than the Aerated batch, but both had gone lower than the predicted FG of 1015. The H2O2 batch sample taste and aroma were again much stronger than the Aerated batch, but both had cleared most of their green beer flavours and the H2O2 batch had lost the puckering after taste.

So in conclusion, I can't say that the H2O2 has ruined the fermentation stage or killed off all the yeast, but it is indicative that the H2O2 batch has attenuated lower (I know it's slight) and produced a yeast that seems to be under stress (especially as this is a highly flocculant variety).

Further updates will take place as planned with the testing for oxidation of the final product over the next months.

View attachment Vienna H2O2 experiment 26 02 17.docx

Milled grist


Brewery set up at Mash stage to show I have no fancy set up (all gravity set up)


Yeast blow out prior to second clean up at 56 hours


EDIT - * I say reported as I have never used O2 in brewing.

** Notes only complete up until today

 

[peteru]

Thank you very much for that report.

I have just today kegged (and bottled) the results of my side-by-side comparison. I did one batch with 10mL of 6% H2O2 and one batch with about 5 minutes of drill+paint stirrer aeration.

Both the fermentation process and the resulting aroma/flavour at bottling time were the same. Both batches ended up at the same FG and as far as I can tell got there at either the same time or within 24 hours of each other. I also observed that the H2O2 sample was cloudier than the aerated sample. The H2O2 sample seems to have slightly better head retention and lacing on the glass.

Based on this side-by-side comparison, I would conclude that there is no clearly visible benefit to using H2O2 vs vigorous aeration. I also don't think there is a detriment.

The only differences I could see (turbidity, lacing and head retention) can possibly be explained by the mechanical aspect of aeration, rather than the O2 content in the wort.

Not exactly the same results as yours, but the conclusion seems similar - H2O2 is not a silver bullet. Unfortunately I have no pure O2 experience to compare against. From all the comments in the forums, pure O2 gas should deliver a clear difference.

 

[mstrelan]

For another experiment you might like to compare H2O2 to no aeration. If you don't have O2 and can't be bothered to aerate is H2O2 an easy replacement for vigorous shaking?

 

[Jack of all biers]

For another experiment you might like to compare H2O2 to no aeration. If you don't have O2 and can't be bothered to aerate is H2O2 an easy replacement for vigorous shaking?

Not going to prove anything in my opinion. Which is based on my suspicion that H2O2 did not produce much O2 to begin with in my test. It would be good if anyone who had an O2 meter did a couple of mini batches using H2O2 to test how much O2 is convert when added to wort plus yeast. Then someone who had the expertise to determine how much, if any yeast mutation occurs. With my results so far I can GUESS these, but can only say for sure that it seems similar to a barely aerated batch that I once did. I forgot to shake, but was poured from a minimum height (barely aerated). This one also struggled and had yeast hanging about in suspension for a long time (different yeast)

 

[Jack of all biers]

So, an update of the experiment with H2O2 compared to a traditionally Aerated batch at the two month mark.

My findings re fermentation are above, but I have been taste comparing every two weeks, or so for the last two months (but drinking bottles between comparison pairs :drinks: What?) and can say that there is little to no difference (except for one bottle) so far.

I'm not sold on the Yorkshire yeast (too much bread for me), but other than one H2O2 bottle that to me tasted like a shandy (if I didn't open the bottle, pour it myself and have held onto it the whole time, I would have been convinced that someone put lemonade in there). Two mates tasted that same bottle and one said unhelpfully, "it tastes weird" and the other said "It tastes like cardboard". Ah ha, I thought. This mate has no idea about the experiment or any experience with beer flavours (off flavours) other than the barrels he's drunk in his life so far. I was convinced this would spell the beginning of things to come, and it may yet, but H2O2 bottles consumed since show no similar flavours. It's also interesting that I could taste a Lemonade flavour? and he said "cardboard". I'm convinced that that bottle was oxidised, but one bottle proves nothing, so the experiment goes on.

Update of my notes attached.

View attachment Vienna H2O2 experiment 26 02 17.docx

The tasting comparison will go on. Peteru, Techno, Adro, any further results from your experiments that differ from mine so far?

EDIT - Oh and I bought an oxygen wand and stone from Keg King, but haven't got the O2 yet (O2 regulator I have for free so am likely to go with the D size O2 from Bunnings)

 

[peteru]

Wow, Jack of all biers! Comprehensive note taking there. Puts me to shame.

After a few more ad-hoc observations, I have come to the conclusion that there is no detriment in using H2O2 when added just after pitching yeast. However, there is no significant observable benefit either, when compared to vigorous aeration using a paint stirrer and power drill. I guess H2O2 could be used as an alternative to vigorous agitation. Varying the dosage of H2O2 might produce different results, but a lot more data would be required.

I have found that a much bigger influence on the fermentation and the final result is the yeast starter. A large (3L) high krausen active starter has so far produced the best result. Pitching on top of a yeast cake and using a paint stirrer to aerate has also produced good results. All my experimentation was done with a US-05 culture that I have been propagating for about 18 months now.

It kind of makes sense. You can either pitch less active yeast, oxygenate the wort and let the yeast do it's thing in the main batch. Or, you can grab a portion of the wort, stick it on a stirplate with the yeast and let the yeast do "Stage 1." on the stirplate, then combine with the main batch to finish the job. Because you are pitching all of the starter, you are also bringing in all the flavours that develop in Stage 1.

I have been tossing up as to whether my next investment should be an O2 wand or a kegmenter. So far, I am leaning towards choosing a kegmenter, so that I can have a closed system from pitching to serving. I think that's likely to bring more benefit, since I should be able to have an oxygen free process at all times after pitching yeast. The only question there is a method for dry hopping. I'm thinking a HDD magnet holding a hop bag to the roof of kegmenter - remove the magnet to drop the hops on day 3 of fermentation.

 

[Jack of all biers]

Wow, Jack of all biers! Comprehensive note taking there. Puts me to shame.

Call me retentive h34r:

After a few more ad-hoc observations, I have come to the conclusion that there is no detriment in using H2O2 when added just after pitching yeast. However, there is no significant observable benefit either, when compared to vigorous aeration using a paint stirrer and power drill. I guess H2O2 could be used as an alternative to vigorous agitation. Varying the dosage of H2O2 might produce different results, but a lot more data would be required.

My observations exactly. H2O2 as a benefit, nope. As a discernible detriment, nope. Therefore why bother using at all?

I'm still not sold on the whole O2 thing as the stuff is only so soluble at certain temps that to get more than 8 ppm is really only achievable with temps in the 12C or below and even then....? Definitely agree that the more I learn the more important the vitality of the yeast is (and to a certain extent the pitching rate also). But the reason for the O2 wand purchase was that I can spend sweet FA and trial O2 with the old mans O2 tank and reg and if it's the bees knees then I'll purchase an O2 tank. If not, then the want will come in handy for aeration with an air pump or something

I'm also thinking about kegmentor or Fermentasaurus. Like the later, but too small as I generally brew 50L at a time and the former will fit in the fermentation fridge I currently have, but I digress into off topic territory. Keep it up fella love those out there experimental ideas of yours :beerbang:

 

[MHB]

Jack
I'm not trying to knock your results, wouldn't be at all surprised if they were fairly accurate; here is the but, they are anecdotal.
This thread is out to 30 pages and it is full of people saying how much their beer has benefited from using O2; also anecdotal, but very consistent.

I would (speculation) think the amount of benefit obtained from the O2 in the H2O2 is balancing the harm done to the yeast by the H2O2 - zero sum gain.
Verses widely reported benefits from oxygenation... using O2 improves your beer looks like a very good bet.
Mark

 

[Jack of all biers]

Yep. Which is why I'm going to give it a try. Just tried the cheaper H2O2 first to see if there was a cheaper ghetto way. My conclusion (yep knew it was only anecdotal) is exactly as you say. I'm not knocking O2, I just have a healthy scepticism and a tight wallet.

 

[Mardoo]

I'm going to raise the spectre of vitality starters again here. I've continued to use them and cannot speak highly enough of the, well, vitality of the ferments with no further aeration of the wort. I really think the LODO guys should give this a go if they aren't already.

Add your slurry to 500ml 1.040 wort. (Oxygenate if you wish. I haven't been but plan on doing some comparisons.) Spin 4 hours on the plate. Add to wort and ferment. No further aeration needed.

I should mention that I have used this exclusively on ales to this point, but have a lager ferment going at the moment using this protocol. We'll see what happens. Apparently this was started at Coors.

EDIT: FWIW, Further to MHB's post, this too is absolutely anecdotal. Equipment-wise I'm finally getting myself to the point I have a satisfactory amount of control to side-by-side ferments that will hopefully satisfy my process desires (Insert heavy SS breathing here). It's been working for me over the last year and I'm pretty damn happy with the results. I was about to upgrade my O2 setup, but was getting ferments that were too fast and too clean. (This was discussed in one of my other ramblings.) I ran across this technique (said to come from Coors via Colin Kaminsky) and thought I'd give it a go while I saved money for the new O2 setup. Over the last year I've tightened up yeast and ferment processes to the point that over the coming year I'll be able to eliminate most of the variables I can see and do true side-by-sides to test the vitality starter process against both air-based and pure O2 aeration.

 

[Jack of all biers]

Cheers for the reminder mardoo and it's on my list of things to try. I just need to get me a yeast forge when they're back on the market.

 

[Rocker1986]

I've read about that vitality starter method too, but haven't tried it as yet. The problem for me is that I harvest yeast from starters, so it wouldn't work with that process. Maybe I will try it when I get to the last use of strains as I obviously won't be harvesting from them on those particular occasions.

ON another note, really been enjoying the beers I've been making with O2 added at pitching time, along with adjusting the water profile to better suit the styles being brewed. My beers are probably the best they've ever been and hopefully will continue to improve.

 

[Adr_0]

Link here here to an experiment I did along similar lines.

 

[Adr_0]

So, an update of the experiment with H2O2 compared to a traditionally Aerated batch at the two month mark.

My findings re fermentation are above, but I have been taste comparing every two weeks, or so for the last two months (but drinking bottles between comparison pairs :drinks: What?) and can say that there is little to no difference (except for one bottle) so far.

I'm not sold on the Yorkshire yeast (too much bread for me), but other than one H2O2 bottle that to me tasted like a shandy (if I didn't open the bottle, pour it myself and have held onto it the whole time, I would have been convinced that someone put lemonade in there). Two mates tasted that same bottle and one said unhelpfully, "it tastes weird" and the other said "It tastes like cardboard". Ah ha, I thought. This mate has no idea about the experiment or any experience with beer flavours (off flavours) other than the barrels he's drunk in his life so far. I was convinced this would spell the beginning of things to come, and it may yet, but H2O2 bottles consumed since show no similar flavours. It's also interesting that I could taste a Lemonade flavour? and he said "cardboard". I'm convinced that that bottle was oxidised, but one bottle proves nothing, so the experiment goes on.

Update of my notes attached.

Vienna H2O2 experiment 26 02 17.docx

The tasting comparison will go on. Peteru, Techno, Adro, any further results from your experiments that differ from mine so far?

EDIT - Oh and I bought an oxygen wand and stone from Keg King, but haven't got the O2 yet (O2 regulator I have for free so am likely to go with the D size O2 from Bunnings)

To answer your question, it seems like H2O2 does actually add oxygen, and yeast is able to reduce this. Saw this consistently in my tests. And even a 160ppm dose into a 150mL starter didn't kill the yeast, so that's nice.

Gravity wise, haven't seen a big change - it's been only 12hrs though.

Sensory indicators will be the big test.

 

[mtb]

I reckon that deserves its own thread Adro

 

[klangers]

Great job Adrian.

Are we sure that there's nothing else from peroxide that could cause oxidation? My quick skim of wiki on methylene blue indicates that it does go blue in any oxidative environment. Interesting that you can create peroxides from it too.

Anyway, I'll pipe down as I'm a mechanical fella

Other uses[SIZE=small][edit][/SIZE]

Redox indicator[SIZE=small][edit][/SIZE]
Methylene blue is widely used as a redox indicator in analytical chemistry. Solutions of this substance are blue when in an oxidizing environment, but will turn colorless if exposed to a reducing agent. The redox properties can be seen in a classical demonstration of chemical kinetics in general chemistry, the "blue bottle" experiment. Typically, a solution is made ofglucose (dextrose), methylene blue, and sodium hydroxide. Upon shaking the bottle, oxygen oxidizes methylene blue, and the solution turns blue. The dextrose will gradually reduce the methylene blue to its colorless, reduced form. Hence, when the dissolved dextrose is entirely consumed, the solution will turn blue again.

Peroxide generator[SIZE=small][edit][/SIZE]
Methylene blue is also a photosensitizer used to create singlet oxygen when exposed to both oxygen and light. It is used in this regard to make organic peroxides by a Diels-Alder reaction which is spin forbidden with normal atmospheric triplet oxygen.

 

[Adr_0]

Great job Adrian.

Are we sure that there's nothing else from peroxide that could cause oxidation? My quick skim of wiki on methylene blue indicates that it does go blue in any oxidative environment. Interesting that you can create peroxides from it too.

Anyway, I'll pipe down as I'm a mechanical fella

I think what you're asking is if there are other oxidation products that don't necessarily represent delicious dissolved oxygen? That's an excellent question actually, and perhaps Lyrebird_Cycles or Dr Smurto can shed some light.

It may be worth repeating the DO testing with an instrument rather than extremely dodgy colour indication in a yellow/red beer. Hopefully gravity and flavour/aroma/visual indicators will provide useful information though, and support the DO/oxidation numbers.

 

[Jack of all biers]

Dr Smurto answered it in this post on the previous page.

I've only very briefly skimmed the discussion on H2O2.

A few points from a scientist whose research area involves H2O2 and O2 in juice/wine; similar situation holds with wort/beer.

Firstly, the reason why O2 is used and not H2O2 is that O2 can't react with organic compounds. This is what is called 'spin forbidden' and is a very fundamental principle of chemistry relating to the configuration of the electrons in the atom. It first reacts with transition metal ions to produce the superoxide radical which can then react with organic compounds. Yeast can mop up the oxygen very rapidly and in a medium that contains only trace amounts of reactive transition metals in the required oxidation state, it will do so before much, if any damage is caused by oxygen via the superoxide radical. We have measured the speed in which yeast uses up all the oxygen in juice and it is very fast, in the order of minutes. We can also measure oxidation markers to see what chemical effects are being caused by O2 introduction and the result is negligible. Our oxygen sensors measure down to ppb levels of oxygen.

This is not the case with hydrogen peroxide, it is very capable of reacting with organic compounds or just about anything it comes into contact with. This is not a selective process, you can't expect yeast to protect the wort from H2O2 as it cannot prevent every single molecule of H2O2 from colliding with other molecules in the wort. Adding an incredibly powerful oxidiser to your wort is not a particularly well thought out method of adding O2.

EDIT - + 1 for the DO instrument testing and mutation observations on the yeast themselves would be the next step.