Bottled Oxygen or Air for "oxygenating" the FV

The yeast prefer to use the energy from oxygen metabolism when they're processing the lipids in the wort into sterols to strengthen cell walls and support reproduction via budding. They don't have to use oxygen metabolism, but it's much quicker and provides more energy.

As oxygen is only used in the sterol generation, it's useful if the fermentation is going to stress the yeast. So things like a big beer, a big batch, your pitch isn't that healthy or big enough, or you're fermenting cold.

I brew relatively small batches, so I think I can get away with focusing on a healthy yeast pitch rather than deal with the complication of oxygenation. If I started brewing bigger batches, I'm pretty sure it'd be something I looked at.

Also if you're adding oxygen you should make sure there's some lipids in your wort the yeast can use in creating the sterols. That's either via having slightly cloudy wort or adding a yeast nutrient. Cloudy wort is easy, but many brewers avoid it because of the chance of bringing across oxidative materials in the trub along with the lipids. So if you're going for a clear wort approach and using oxygen you may want to look at a yeast nutrient as well.
 
Lots of great info here. Thanks to all that have contributed.

Maybe we need another EVENT in the Brew Session list to include Oxygenating Method / times etc.
@Pricelessbrewing Maybe this could be incorporated?

I will now look out for a reasonably cheap method of Oxygen supply and regulator so I can get better Lager brewing - due to the lower temperature fermenting conditions. I already have the fish tank pump and I splash a lot anyway (well so my wife tells me lol).
 
The yeast prefer to use the energy from oxygen metabolism when they're processing the lipids in the wort into sterols to strengthen cell walls and support reproduction via budding. They don't have to use oxygen metabolism, but it's much quicker and provides more energy.

As oxygen is only used in the sterol generation, it's useful if the fermentation is going to stress the yeast. So things like a big beer, a big batch, your pitch isn't that healthy or big enough, or you're fermenting cold.

I brew relatively small batches, so I think I can get away with focusing on a healthy yeast pitch rather than deal with the complication of oxygenation. If I started brewing bigger batches, I'm pretty sure it'd be something I looked at.

Also if you're adding oxygen you should make sure there's some lipids in your wort the yeast can use in creating the sterols. That's either via having slightly cloudy wort or adding a yeast nutrient. Cloudy wort is easy, but many brewers avoid it because of the chance of bringing across oxidative materials in the trub along with the lipids. So if you're going for a clear wort approach and using oxygen you may want to look at a yeast nutrient as well.
I don't mean to be disagreeable, but this is not the general consensus of the of the brewing industry or yeast manufacturers. Below are some quotes from White Labs about liquid yeast requirements. As I said before, dry yeast already has lipids and sterol reserves.

"Yeast use oxygen for cell membrane synthesis. Without oxygen, cell growth will be extremely limited. Yeast can only produce sterols and certain unsaturated fatty acids necessary for cell growth in the presence of oxygen.

Inadequate oxygenation will lead to inadequate yeast growth. Inadequate yeast growth can cause poor attenuation, inconsistent or long fermentations, production of undesirable flavor and aroma compounds, and produces yeast that are not fit for harvesting and re-pitching.

Some yeast strains have higher oxygen requirements than others. It is generally safe to assume that you need at least 10ppm of oxygen. 10ppm will supply adequate oxygen in most situations. Over-oxygenation is generally not a concern as the yeast will use all available oxygen within 3 to 9 hours of pitching and oxygen will come out of solution during that time as well. Under-oxygenation is a much bigger concern.

High original gravity (>1.065) wort, in addition to increasing osmotic stress on yeast, can cause problems with achieving adequate levels of dissolved oxygen. As the gravity of wort increases, solubility of oxygen decreases. Increased temperatures also decrease the solubility of wort.

The unsaturated fatty acids found in wort trub can be utilized by yeast for membrane synthesis. If wort trub levels are low, yeast will need to synthesize more of these lipids and therefore will require more oxygen."

This is why pure oxygen works best, it can get the levels of dissolved oxygen higher than the maximum 7ppm available with just the atmosphere. This is especially true for higher gravities or higher temperature wort.
 
@HighVoltageMan! I don't see it as disagreeable. Any bits in particular?

The outcome is the right amount of healthy yeast. That's strain and beer dependent, of course, and there's multiple ways to get there for me as I brew small batches. You definitely need some growth as that's where esters are generally created and for a bunch of the beers I brew the esters are important, but do I need the 10 ppm of O2 that's needed for growth of 10-12 times the original pitch? Or as I'm a small batch brewer I can get away with the standard 5 times growth that comes from atmosphere as oxygenation.

I can see that once batch sizes increase, you edge closer and closer to the 10-12 times original pitch growth requirement. And once you're past 5-6 ppm you'll definitely need pure O2.
 
I don't mean to be disagreeable
... and you are not. I think you are disagreeing, perhaps, but quite pleasantly. It is not an attack to question data by supplying more data.

Anyhow...

I think the issue is "how much us enough" at the homebrew scale. For typical 1.060 brews, air seems to be working for me.

It riled me to pay $11 for 1.4 ounces of Oxygen, so I switched to an aquarium pump. So far that's working, but it seems there can be room for improvement. I'll not abandon the quest for a bigger oxygen bottle.
 
I can see that once batch sizes increase, you edge closer and closer to the 10-12 times original pitch growth requirement. And once you're past 5-6 ppm you'll definitely need pure O2.
Pitch rates are linear. They are based on gravity and volume. If the gravity or volume increases, so does the pitch rate. Whether you pitch into a 4 liter batch or 1000 hectoliter, the pitch rate remains the same. Growth rates remain relatively the same, about 5-6 times for ales and 3-4 or so for lagers. Overpitch may give you a hedge against low levels of oxygen, but it's not without risking an inferior beer. A beer can tolerate a underpitch with properly aerated wort better than an overpitch with low levels of oxygen. You can successfully ferment a beer with aeration without pure oxygen no doubt, but the quality of the beer benefits immensely from higher oxygen levels. Trub can contain some of the fatty acids the yeast needs, but it's typically less than what is required. There are very few, if any pros who don't use oxygen to aerate. There is no debate within the industry about the oxygen levels in wort at pitching, it's a well researched and established. Better attenuation, better yeast health, lower levels of undesired flavor/aroma components, lower levels of high alcohols and consistent yeast performance.

Aerating with oxygen is a simple solution that homebrewers can do to insure healthy yeast and fermentation, It contributes to consistent outcomes and consistency batch to batch. The idea is that since homebrewers and most craft brewers don't have DO meters or labs to send the wort for analysis, the simplest solution is to aerate slightly more than may be needed. The risk of low oxygen levels are much greater than high levels. Unless the brewer is completely careless, the beer does not suffer from aerating with oxygen. There is almost no downsides to oxygen other than cost.

Many homebrewers do not aerate with oxygen and are happy with it. For me, it was the one thing I did that had the biggest impact on the overall quality of my beer. New homebrewers should at least hear the benefits of it.

I think you bring up some good points and I think that civil discussions help everyone, including me. It causes me to rethink my brewing practices I have taken for granted.
 
I use dry yeast. It's much more forgiving. I come from the days before star san when we used bleach to sanitize, so we definitely didn't have oxygen tanks. I've always just shake the bajezus out of the fermenter for 5 mins and never had an issue myself.
 
I don't brew much beer over 1.055 OG but I do reuse my yeast I buy for multiple generations so I've opted for yeast nutrient as a way of maintaining a healthy yeast culture.
I ventured down the rabbit hole of Oxygenation and settled on the splash method for airation very unscientific. one caviate I use where possible airation below 20c as it's more likely to absorb at lower temperatures. To bad with Kviek . .

Also reading brulosophys exbeeriments on wort oxygenation left me a little more relaxed as well.
Now if an O2 Bottle option were cheaper id use it especially with these bubble fermentors I'd effectively trap any o2 addition in with the wort shake it and leave it.


Here's two exbeeriments I found I interesting
https://brulosophy.com/2018/12/03/w...east-into-a-high-og-beer-exbeeriment-results/

https://brulosophy.com/2021/03/29/w...-on-a-british-golden-ale-exbeeriment-results/
 
...Now if an O2 Bottle option were cheaper id use it especially with these bubble fermentors I'd effectively trap any o2 addition in with the wort shake it and leave it...

HighVoltageMan has now made me paranoid, well in combination with Chris White talking about 10 million cells/milliliter/degree plato for imperial beers. So I had a look around the kegland website. Doesn't look as expensive for us as the posts earlier in this thread - https://www.kegland.com.au/pure-oxygenation-wand-kit.html. So I'll probably pick one up next time the O2 cylinders are back in stock. Which could be a while.
 
HighVoltageMan has now made me paranoid, well in combination with Chris White talking about 10 million cells/milliliter/degree plato for imperial beers. So I had a look around the kegland website. Doesn't look as expensive for us as the posts earlier in this thread - https://www.kegland.com.au/pure-oxygenation-wand-kit.html. So I'll probably pick one up next time the O2 cylinders are back in stock. Which could be a while.
So $90 for the wand the o2 cylinder and the regulator yup one for the bucket list.
 
Well here, in the UK, you are banned from buying medical oxygen! It can ONLY be purchased by doctors, medical clinicians etc. You can breathe oxygen but not allowed to buy it! Oxygen for welding is ok. Work that one out. Anyway. Buying an oxygen bottle and the regulator is an expensive route - if you only do 20 brews a year - the main thing is the bottle is cheap to fill if you use oxygen for welding but you have to RENT the bottle - at 2/3 cost over all. eg. 10lt oxygen costs £35 - the rest of rental and tax = £70. I don't think I will be usinf Oxygen soon.
 
Well here, in the UK, you are banned from buying medical oxygen! It can ONLY be purchased by doctors, medical clinicians etc. You can breathe oxygen but not allowed to buy it! Oxygen for welding is ok. Work that one out. Anyway. Buying an oxygen bottle and the regulator is an expensive route - if you only do 20 brews a year - the main thing is the bottle is cheap to fill if you use oxygen for welding but you have to RENT the bottle - at 2/3 cost over all. eg. 10lt oxygen costs £35 - the rest of rental and tax = £70. I don't think I will be usinf Oxygen soon.
On top of this i think if you brewed a lot of 1.065+ OG beers you'd get bang for your buck but for me brewing at most 1.040-50 beers I'll stick with a good pitch rate.

I'd use it for big beers.
 
Well here, in the UK, you are banned from buying medical oxygen! It can ONLY be purchased by doctors, medical clinicians etc. You can breathe oxygen but not allowed to buy it! Oxygen for welding is ok. Work that one out. Anyway. Buying an oxygen bottle and the regulator is an expensive route - if you only do 20 brews a year - the main thing is the bottle is cheap to fill if you use oxygen for welding but you have to RENT the bottle - at 2/3 cost over all. eg. 10lt oxygen costs £35 - the rest of rental and tax = £70. I don't think I will be usinf Oxygen soon.
Hint: The medical oxygen and the welding oxygen come from the same tank. Oxygen is fractionally distilled from liquid air so if there's anything in it, it would be small quantities of nitrogen and miniscule quantities of the rest of the components of air. My n=1 observation: I've used welding O2 for years with no ill effects, either to the yeast or to me.
 
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Well here, in the UK, you are banned from buying medical oxygen! It can ONLY be purchased by doctors, medical clinicians etc. You can breathe oxygen but not allowed to buy it! Oxygen for welding is ok. Work that one out. Anyway. Buying an oxygen bottle and the regulator is an expensive route - if you only do 20 brews a year - the main thing is the bottle is cheap to fill if you use oxygen for welding but you have to RENT the bottle - at 2/3 cost over all. eg. 10lt oxygen costs £35 - the rest of rental and tax = £70. I don't think I will be usinf Oxygen soon.
We can't allow the commoners to have oxygen next thing you know....
 
Working at a nursing home ATM doing Inspections a bloke in a room was on Oxygen I asked him about the machine it makes the pure oxygen on demand and filters out all the nasties pretty bloody cool.

If he goes mobile he takes a 02 Bottle.

Here it is
https://www.boc.com.au/shop/en/au/medical-equipment/oxygen-concentrators/inogen™-one™-g5-portable-oxygen-concentrator-is-500-au8-p
$4k for the unit:eek:

Both my parents were on Oxygen near the end of their lives. Good thing I wasn't brewing back then. "Hey Dad, do you mind if I borrow your nasal canula for a 60 seconds?" :p
 

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