O2-ing my wort

[klangers]

You can aerate with oxygen

You can aerate with air, which is 20% oxygen. You just need more time/exposure. On a home brewing scale it's easy as piss to oxygenate sufficiently without oxygen - just go 5 times longer!

The main reason why pure oxygen might be perceived to perform better is that the comparisons with air have been carried out with air with impurities.

And like anything, as already mentioned, it is possible to over-oxygenate your wort.

Pure oxygen is incredibly reactive (ie dangerous). Using equipment not designed for oxygen use can result in corrosion and failure of the regulator. You do not want an oxygen bottle regulator failing around even mildly flammable materials.

 

[kaiserben]

it's easy as piss to oxygenate sufficiently without oxygen - just go 5 times longer!

My understanding is that the absolute most oxygen you can get into your wort by shaking (or using air, for example with an aquarium pump) is 8ppm. Shake it for as long as you want, but you won't get past 8ppm.

 

[nosco]

Any one using nutrients as well as o2?

 

[Mardoo]

Absolutely.

 

[GalBrew]

As said above you can pump air into your wort until the cows come home but you won't get more than about 8ppm. Lagers in particular more than that, so the only way you bare going to get it is with pure oxygen.

 

[Danscraftbeer]

Any one using nutrients as well as o2?

I used a (drop) = 0.1g of nutrient in the starter with M07 for a Stout put down a week ago. 20lt I oxygenated the wort in a 30lt fermenter with a SS airstone moved around the wort gently so, lid on. Until the head filled the 10lt space. That was only about a minute I think. :chug: Unknown o2 level but then pitched the starter in and ferment was explosive!
Blown airlock and mess then blow off tube into a jar was worthy of video but I didn't bother. It could have run a small like steam engine or something.

 

[nosco]

Ok im sold.

 

[nosco]

Olive oil? Ok im joking before anyone replies.

 

[Mardoo]

"It rubs the oil on its skin…"

 

[nosco]

Ill stick with the lotion Mardoo.

 

[Bribie G]

As said above you can pump air into your wort until the cows come home but you won't get more than about 8ppm. Lagers in particular more than that, so the only way you bare going to get it is with pure oxygen.

That's why I've just bought an oxy kit as I've decided to do some proper lagers this year for the comps.

Running up a 5L batch of 1040 wort today with a stockpot BIAB and going to oxygenate each wort addition as I go.

 

[Howlingdog]

What sort of oxy kit Bribie G?

 

[DJ_L3ThAL]

Just for reference, I suggest even though the bottle are setup and handled 'differently', the grades of oxygen in terms of purity/cleanliness will be extremely similar if not identical. Reason being as I've raised before are oxygens super ability to support combustion of ANY materials. So 'suppliers' won't risk crap/contaminants getting into the oxygen to avoid law suits from hurting people or damaging equipment with exploding regulators or process machinery.

Use OXYGEN CLEAN AND COMPATIBLE equipment ONLY with oxygen, the hazards are real.

 

[Bribie G]

What sort of oxy kit Bribie G?

Brewman's

Should be here on Fastway today.

 

[nosco]

Pitched a pils yesterday with s128 @9c. O2 for 60sec and yeast nutrient disolved in some cooled kettle water.
24hrs later @ 10.5c a nice 1cm thick krausen.

 

[gezzanet]

Brewman's

Should be here on Fastway today.

Got a brewman's O2 rig last Xmas also using nutrient in boil. Ferments seem a lot better as a result [emoji106][emoji106]

 

[nosco]

I did chill the cube to 7c just to see how it would work but after trnfering to a fermenter and mucking about it had warmed up to 9c.

 

[klangers]

As said above you can pump air into your wort until the cows come home but you won't get more than about 8ppm. Lagers in particular more than that, so the only way you bare going to get it is with pure oxygen.

Mmm, my original post was overly simplistic. Certainly there are solubility limits which are affected by temperature, pressure and dissolved solids. Indeed, at a given ambient temperature and pressure, pure oxygen will dissolve roughly 5x more into a medium than oxygen in the air. The rate at which the oxygen dissolves is a bit more complex to assess. My original point, which wasn't clearly articulated, is that up to this theoretical solubility limit, air works just as well.

Do we really need >8ppm? The only reason that I can think of is that you're under-pitching yeast, and it needs additional oxygen for the aerobic growth phase. I understand that it may assist with decreasing lag time, but I'm not sold on the concept as a one-size-fits-all approach especially in home brewing where I'm happy to wait a couple more days. To me it's cheaper and easier to prop my yeast up and aerate with air rather than frigging around with another yet another compressed gas cylinder etc.

Personally I don't like to add things to my brews that I can't measure. How do you know when you've added enough oxygen? It's not something you want to be pouring down the drain, so to speak. An ex-brewer (who happens to hold a brew master qualification) colleague at work said that it is entirely possible to over aerate too, especially if you're looking for a particular yeast flavour profile. He could be full of shite, too. I don't know.

Oxygen was only available rather recently in brewing history - how was aerating a lager done in early 1900s for example?

Not trying to be clever, but genuinely interested in the true science behind it all.

 

[GalBrew]

In the Yeast book, there is a section on the ppm required for different ferments. Lagers in particular are recommended to have more than 8ppm (can remember what is was off the top of my head), which you cannot achieve with an air pump. Why can't we measure oxygen anyway? DO meters are available (albeit a little pricey), I have an oxygen flow meter, which while it does not measure the DO in the wort, it allows you to measure the volume of oxygen you inject into it (there are fudge figures correlating flow rates to ppm in the book too I believe) and while not the most accurate method of measurement it does allow for repeatability of process. It's also not that hard, it only takes a couple of minutes with the setup I have. I'm not sure where all the fuss about how 'difficult' it is comes from. If you don't want work for your beer I'm sure uncle Dan will hook you up with no work at all.

I've also heard that is it possible to over do it with oxygen which is why I like the flow meter.

Also there are many technological improvements that have been incorporated into brewing over the centuries, do you eschew things such as thermometers, hydrometers, pure yeast culture, hops etc.? If your aim is to emulate the brew of a medieval monk then fine, but why the issue with oxygen? If you don't want to use it thats fine, but you can't give the wort the recommended levels of oxygen for certain fermentations without it.

 

[Bribie G]

Allsopp's lager brewery in London in the early 1900s fermented in closed glass-lined tanks under filtered sterile AIR pressure for the first part of the fermentation so that oxygen from the air would replace oxygen taken up by the wort. (edit, by the yeast).

Initial aeration was from wort run as a waterfall down arrays of chilled pipes into troughs where it flowed away into the fermenters.

The extra aeration could be done by opening the FV and thrashing with whisks or slotted spoons as I actually do for my Yorkshire Bitters but the O2 for me is a do once, set and forget method.

edit again: For my lagers I intend to quick chill in two lidded SS stockpots in tub full of ice water then pour into conical. That will be a smooth pour so there's going to be little agitation compared to my normal (for ales) glug and gloop transfer out of plastic cubes into FV, and way too little oxygenation.