How do you O2.

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mr_wibble

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Right, so O2.

The first time I saw it used was on a course at this place: All Gain Brewing, Boolaroo.
At the time he cooled the wort, the O2 was injected in-line (with a T-piece air-stone) as the wort went from the chiller into the fermenter. I remember that there was only a very small amount of bubbles visible in the sight-glass thing.

A bit after that I bought my O2 kit from MHB (now Brewman).

The general reading on it says to wave it around in the mix for 60 seconds. Lately I found something that said 60 seconds was a minimum, and 90-120 seconds was OK. But the Wyeast page says 60 seconds. Too much O2 can cause the yeast to stall the fermentation[1]. However I have not seen this personally. Wyeast says under-oxygenating is a much greater problem than over O2ing.

So, what do *I* do?

I set the O2 pressure such that it's producing a lot of tiny bubbles. If it gets to the point where it's bubbling up like blowing through a straw into a milkshake, I turn it down. I figure big bubbles don't have time or the surface area to dissolve well. When I get it to this point, I then stir vigorously and count in my head to 90 (but previously to 60). I get a thickish foam on the top of the wort - a lot like a kräusen.

But what do you do?


[1] http://discussions.probrewer.com/showthread.php?28004-Too-much-oxygen&s=32f81f3bacc2344d6eeeb975113e3926&p=91493#post91493 .
 
I don't yet, but have been contemplating making my own o2 with hydrogen peroxide n yeast, filling a balloon then into wort. Thinking will be cheaper and relatively easy. Only early stages of research but the basic chemistry is safe lol
 
I went the big bottle from Bunnings set up. Will probably last me two lifetimes. I only use the air stone for stir plated starter. Turn it on for lowest setting then turn the bottle off and it still bubbles a lot until the pressure in the hose runs out.
For the wort I pressure ferment in a 50lt kegmenter and a 23lt kegmenter. I simply fill with the new wort and pitch the yeast then seal.
Then connect via a gas/white disconnect with a meter of hose and pump in o2 to get to 5 to 10 psi. Not really exact science. Disconnect then tip kegmenter on its side and rock and roll shake the wort hard for say 3 minutes for some exercise. Then immediately take a hydrometer sample from the beer out via a black disconnect and a meter of hose . That hydrometer sample then sits in the temp control fridge with the kegmenter as an indicator of how the ferment is progressing. :)
 
SCR29 said:
I don't yet, but have been contemplating making my own o2 with hydrogen peroxide n yeast, filling a balloon then into wort. Thinking will be cheaper and relatively easy. Only early stages of research but the basic chemistry is safe lol
This is in jest, yes?
 
I let it gurgle through a stainless air stone for three to four minutes. It has definitely improved my kit beers they are much clearer and clean tasting.

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I use a disposable bottle from bunnings with an eBay reg. I have a stone connected using some PVC tubing.

I have been setting the reg to approximately 1L/min for 60 seconds and moving the stone around the bottom of the fermenter. The bottle holds about 100L of O2 so I should be close up to 100 batches from a bottle which makes it relatively inexpensive. (~80c/batch)

Night and day difference between beers with and without O2. Before my beer tasted distinctly like homebrew, now they taste a lot more like beer bought from the shop.

I believe proper oxygenation of wort is as important as temp control for yeast health and beer quality.
 
I got a disposable bottle from bunnings with an eBay reg as well. use a SS stone and wand with PVC tube. I've only done a couple of brews with it. first one i had too high and did for 60 seconds. still worked. second one i had so bubbles just broke the surface and did for 90 seconds. switched to a blow off tube and bottle of starzan at the same time. Glad i did, the yeast goes mental with O2, i think the gladwrap seal would have surely blown :D

As for the taste to be honest i haven't noticed any difference. To me my beers tasted ok before and the taste ok now. Maybe when i rebrew one I've done before I'll notice but for now it makes the ferment a lot more predictable and active and no need to shake the shit out of the fermenter.
 
Neither of those two regulators are rated for O2.... not that we really need another repeat of the last time we went down that rabbit hole! :ph34r:

Anyway I'm just using the kit from G&G, and I turn it on until I can see bubbles and then wind it back until they're just barely making the surface, then leave that for a couple minutes.

Anyway the following reg and bottles would be more appropriate for O2

http://www.ebay.com.au/itm/Bromic-Disposable-Oxygen-Gas-Bottle-Regulator-12mm-Thread-Oxy-Mapp-1811172-/112341047229?hash=item1a280c57bd:g:pZUAAOSw4A5Y2b-Z

http://www.ebay.com.au/itm/Disposable-Gas-Bottle-PURE-OXYGEN-1x-2-2-litre-Bottle-Oxy-LPG-Acet-1811322-/122077785081
 
I doubt they are "rated" for anything. Do you mean it doesn't mention o2 in the eBay listing? I would hardly take that as the official word.

It works, that's good enough for me. Plus it's cheaper.
 
it turns on
it controls the amount of gas
it turns off
it has a gauge that looks the business
 
I've got a BOC oxygen cylinder and regulator which feeds an oxygen wand and I do pretty much the same thing as the OP. There were some charts and other figures posted in another thread recently about over oxygenating and it would appear pretty much impossible to do at the temperatures we generally pitch yeast at, so it's not something that bothers me. I haven't had any stalled ferments since I started doing this, or before it either.
 
eldertaco said:
Neither of those two regulators are rated for O2.... not that we really need another repeat of the last time we went down that rabbit hole! :ph34r:

Anyway I'm just using the kit from G&G, and I turn it on until I can see bubbles and then wind it back until they're just barely making the surface, then leave that for a couple minutes.

Anyway the following reg and bottles would be more appropriate for O2

http://www.ebay.com.au/itm/Bromic-Disposable-Oxygen-Gas-Bottle-Regulator-12mm-Thread-Oxy-Mapp-1811172-/112341047229?hash=item1a280c57bd:g:pZUAAOSw4A5Y2b-Z

http://www.ebay.com.au/itm/Disposable-Gas-Bottle-PURE-OXYGEN-1x-2-2-litre-Bottle-Oxy-LPG-Acet-1811322-/122077785081
I think this is a worthy post because it pays to think about it, may not be applicable but still have a think about it just in case
hate to see an accident, maybe read that post on the non o2 regs ???
 
I don't really worry about the time too much, because there are so many other variables that are unknown which affect the dissolution rate just as much. Just an approximate 30-60 seconds and a flow rate that produces nice even small bubbles from the air stone, rather than giant turbulent bubbles.

The limit of solubility is generally reached fairly quickly too.
 
I just want to add this, possibly unhelpful, remark:

If using O2 makes a tremendous difference to your beer (and it did mine), then one conclusion is that you were probably not aerating so well before O2.
Sure sure, some yeasts want more oxygen than you can get with air alone, but I think the point still stands.
 
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