How Long to Oxygenate wort?

[Danscraftbeer]

What are you guys talking about? Forgive me here as a newb.
You get tanks and hoses and airstones etc to oxygenate your brews? even as small as 20lt brews????

Is there anything wrong with the 2/3 wort / 1/3 headpspace pitched correctly, seal.
Then shake to the *********! Then airlock.
Personally I have found great results that way without the added complications. my opt anyway. B)

 

[Ducatiboy stu]

NB:. I have no view on oxygenating dry yeast....

 

[Ducatiboy stu]

What are you guys talking about? Forgive me for here.
You get tanks and hoses and airstones etc to oxygenate your brews? even as small as 20lt brews????

That was even discussed on Grumpy's :chug:

 

[Cervantes]

My question is when all you have is an 02 tank and a regulator that has units in psi, how do you know what psi will give you a flow rate of 1L/min.

Click on the link in the post below. It's for a cheap meter that will tell you how many litres per minute you are using.Just install it into your air line.

It doesn't take long. I generally oxygenate through a stone for about 30 seconds to a minute.

I've fitted a small oxygen flow meter / control valve similar to this one and throttle it back so that lots of bubbles aren't breaking on the surface and most of the oxygen is being retained in the wort.

 

[TheWiggman]

What are you guys talking about? Forgive me here as a newb.
You get tanks and hoses and airstones etc to oxygenate your brews? even as small as 20lt brews????

Is there anything wrong with the 2/3 wort / 1/3 headpspace pitched correctly, seal.
Then shake to the *********! Then airlock.
Personally I have found great results that way without the added complications. my opt anyway. B)

2 options
Air pump with aeration stone
Pure O2 kit , another example

As for the benefits, it's discussed at length in various threads. Wyeast have a good write-up regarding the tested methods and which methods are suitable for what beers. The 'shake the fermenter' method goes out the door for 60l batches, and still doesn't get desired DO for lagers.

I don't find it complicated at all to dip the aeration stone on, turn on the regulator for 60 seconds, then remove it. If it results in better beer (which to date it has) then it's money well spent. Like I said you don't need to shake the fermenter, nor do you need to step mash, nor add nutrient, nor fine etc. to get 'great results' but if those things didn't make a difference why would anyone do it?

And yes far be it for home brewers to want to complicate processes...

 

[bshb]

For starters I don't think it is possible to achieve an oxygen concentration of 15ppm in beer wort. At 20C the maximum you can achieve is 9.2ppm and at 10C the maximum is 11.3ppm and this is in water (so will be less in wort). This saturation limit holds regardless of whether you use air or pure oxygen to oxygenate your wort, although it may be difficult to reach saturation using just air. I think it is almost impossible to over oxygenate wort, most of the oxygen will simply not be absorbed. There is also another factor at play and that is the higher the SG the less soluble oxygen will be in the wort. That said I use 1L/min pure oxygen for 1 minute for an average SG ale and increase this to 1.5 minutes for 1.065-1.080 ale then up to 2 mins for over 1.080, and for a really big beer say over 1.100 say 2.5 mins. The extra oxygen may not solubilise in the wort, but will be present in the headspace and replenish oxygen levels in the wort over the first few hours as the oxygen is consumed.

not sure this necessarily true, apparently in a continuation of white labs oxygen study (from yeast: the practical guide to beer fermenting) they measured the dissolved oxygen levels of 12 craft breweries and found that 9 were under 9ppm, 1 was bang on 9ppm, and 2 were above 23ppm. so i think that you can over oxygenate (which can lead to increased fusel alcohols, increased acetaldehyde).

if you are brewing a RIS i'd make sure you give it more oxygen after 12-18 hours this will help with cell vitality and attenuation. i'd just go with 1 minute then 1 minute 15 hours later and see how it attenuates, if it doesn't fall enough add more next time.

 

[Black n Tan]

not sure this necessarily true, apparently in a continuation of white labs oxygen study (from yeast: the practical guide to beer fermenting) they measured the dissolved oxygen levels of 12 craft breweries and found that 9 were under 9ppm, 1 was bang on 9ppm, and 2 were above 23ppm. so i think that you can over oxygenate (which can lead to increased fusel alcohols, increased acetaldehyde).

if you are brewing a RIS i'd make sure you give it more oxygen after 12-18 hours this will help with cell vitality and attenuation. i'd just go with 1 minute then 1 minute 15 hours later and see how it attenuates, if it doesn't fall enough add more next time.

Yes I have read this in the yeast book. I suspect the higher DO seen is likely due to greater pressure seen in large commercial conical fermenters or may be an artefact. There is a plethora of information in the scientific literature about oxygen saturation level, so I stand by my claim that on a home brew scale I believe it almost impossible to over-oxygenate the wort. The relationship between oxygenation and fusel alcohols and acetaldehyde seems complex, with a lot of contradictory evidence as whether high or low oxygenation causes these things.

 

[professional_drunk]

I've been oxygenating my wort for a while now. Recently I did a 1.046 wort with wyeast ringwood ale and I had accidentally run out of o2 so it didn't get my usual treatment and I didn't do any manual methods for introducing o2. This beer turned out fantastic btw. I'm starting to suspect that the importance of o2 may either be

• yeast strain dependant
• not required for yeast that's been exposed to o2 on a stir plate
• only relevant for repitching

As for dry yeast, I did once try oxygenating a 1.055 wort that I was using notto in and the beer turned out horribly oxidized. It's as if the yeast had it's fill of o2 and left it in the wort.

I've got another wort of 1.048 ready to pitch with stir plated yeast. I'm going to try pitching it without o2 and see if I get the same results.

 

[Cervantes]

As for dry yeast, I did once try oxygenating a 1.055 wort that I was using notto in and the beer turned out horribly oxidized. It's as if the yeast had it's fill of o2 and left it in the wort.

I've got another wort of 1.048 ready to pitch with stir plated yeast. I'm going to try pitching it without o2 and see if I get the same results.

Apparently dry yeast doesn't need to be oxygenated.

From the Danstar Website

I always aerate my wort when using liquid yeast. Do I need to aerate the wort before pitching dry yeast?
No, there is no need to aerate the wort but it does not harm the yeast either. During its aerobic production, dry yeast accumulates sufficient amounts of unsaturated fatty acids and sterols to produce enough biomass in the first stage of fermentation. The only reason to aerate the wort when using wet yeast is to provide the yeast with oxygen so that it can produce sterols and unsaturated fatty acids which are important parts of the cell membrane and therefore essential for biomass production.

Edit:

However it does say......

If the slurry from dry yeast fermentation is re-pitched from one batch of beer to another, the wort has to be aerated as with any liquid yeast.

 

[Danscraftbeer]

2 options
Air pump with aeration stone
Pure O2 kit , another example

As for the benefits, it's discussed at length in various threads. Wyeast have a good write-up regarding the tested methods and which methods are suitable for what beers. The 'shake the fermenter' method goes out the door for 60l batches, and still doesn't get desired DO for lagers.

I don't find it complicated at all to dip the aeration stone on, turn on the regulator for 60 seconds, then remove it. If it results in better beer (which to date it has) then it's money well spent. Like I said you don't need to shake the fermenter, nor do you need to step mash, nor add nutrient, nor fine etc. to get 'great results' but if those things didn't make a difference why would anyone do it?

And yes far be it for home brewers to want to complicate processes...

hah, cool.
I'll probably have a crack at it some day too. I could only opt for the bottled pure O2 method.
I aerated water for a can brew in the past then thought twice about doing it again. Just wouldnt want to blow open air with wild yeasts via rubber diaphrams through my wort.
Watched a lengthy video of a class run by Northern Brewer explaining that for small (shakable size) brews then 1 minute shaking is enough to achive up to 8ppm. Shaking longer wont really achieve any more DO. But I still shake for 4 minutes. Bout the hardest exercise I do of late... -_-

 

[verysupple]

Sorry to dig up an old thread, I've been researching using O2 rather than shaking the FV and came across some info that's relevant.

not sure this necessarily true, apparently in a continuation of white labs oxygen study (from yeast: the practical guide to beer fermenting) they measured the dissolved oxygen levels of 12 craft breweries and found that 9 were under 9ppm, 1 was bang on 9ppm, and 2 were above 23ppm. so i think that you can over oxygenate (which can lead to increased fusel alcohols, increased acetaldehyde).

if you are brewing a RIS i'd make sure you give it more oxygen after 12-18 hours this will help with cell vitality and attenuation. i'd just go with 1 minute then 1 minute 15 hours later and see how it attenuates, if it doesn't fall enough add more next time.

Yes I have read this in the yeast book. I suspect the higher DO seen is likely due to greater pressure seen in large commercial conical fermenters or may be an artefact. There is a plethora of information in the scientific literature about oxygen saturation level, so I stand by my claim that on a home brew scale I believe it almost impossible to over-oxygenate the wort. The relationship between oxygenation and fusel alcohols and acetaldehyde seems complex, with a lot of contradictory evidence as whether high or low oxygenation causes these things.

It also says in the Yeast book that when White Labs did experiments using 20 L @ 1.077 that 14.08 ppm was achieved using O2 at 1 L/min through a 0.5 micron stone for 2 minutes. So apparently it may not be just fermenting under pressure that allows commercial breweries to achieve greater than 10 - 12 ppm. The Wyeast website also suggests that it's possible to get greater than that concentration.

The O2 saturations in water that BnT quoted are for water exposed to air and are determined in most part by the partial pressure of O2 in the air (that's why higher pressure gives a higher saturation point). If the head space in an FV has a higher concentration of O2 than atmospheric air - which is likely when injecting with a sintered stone - then the saturation point changes.

Also note that it's possible to get supersaturation. So even when exposed to normal atmospheric air it's possible to temporarily have greater than 100 % saturation. If this is the case then the higher DO levels observed immediately after oxygenation would relatively quickly drop to or below saturation. However as above, the head space is likely to be oxygen rich which would slow the rate of loss and raise the saturation point.

 

[Black n Tan]

Sorry to dig up an old thread, I've been researching using O2 rather than shaking the FV and came across some info that's relevant.



It also says in the Yeast book that when White Labs did experiments using 20 L @ 1.077 that 14.08 ppm was achieved using O2 at 1 L/min through a 0.5 micron stone for 2 minutes. So apparently it may not be just fermenting under pressure that allows commercial breweries to achieve greater than 10 - 12 ppm. The Wyeast website also suggests that it's possible to get greater than that concentration.

The O2 saturations in water that BnT quoted are for water exposed to air and are determined in most part by the partial pressure of O2 in the air (that's why higher pressure gives a higher saturation point). If the head space in an FV has a higher concentration of O2 than atmospheric air - which is likely when injecting with a sintered stone - then the saturation point changes.

Also note that it's possible to get supersaturation. So even when exposed to normal atmospheric air it's possible to temporarily have greater than 100 % saturation. If this is the case then the higher DO levels observed immediately after oxygenation would relatively quickly drop to or below saturation. However as above, the head space is likely to be oxygen rich which would slow the rate of loss and raise the saturation point.

Fair point VS and thanks for the pointing out the mistake. I stand corrected and agree that using pure O2 will provide a higher partial pressure and therefore you could achieve higher saturation than the figures I quoted. Bit of a brain fart on that. However I still think in reality that you are unlikely to over-oxygenate at the home brew level and even if you did the yeast would consume the additional oxygen within the first 12-24 hours.

 

[verysupple]

Yeah, I agree over-oxygenation probably isn't an issue for us. Even if you do come into problems from over-oxygenation, just use less next time - problem solved. Well, assuming you can figure out what's causing the problems.

 

[Danscraftbeer]

This is a can of worms I cant help but bite into.
First up! How do you do this oxygenation? You just stick in an airline with an airstone and blow in the 02 (Or surrounding air)?
Is there any other circulation other than whats created by the bubbles? It wont affect the entire wort. There is always dead spots or corners (cubes). o2 wont be circulated evenly.
For an airstone to get DO levels up the levels mentioned throughout the entire contents it would take hours.
Tell me I'm wrong here.
Or shake it as well? This is home brew yeah?



As a layman but care and concern enough. We home brewers can not ever over oxygenated when shaking the friggin fermenter!

ps. if you could be bothered:
I'm also a doer of Aquaponics.
Low DO is not good, fish can die, and many nasties that like low oxygen can happen. Think of yeast the same way.
When raising fish the more DO the better but no concern that you can over do it. Turn your fish tank into a washing machine rolling with pumped air and it just makes the fish move more. That is actually a good thing.
As for OG test results I think averages are more like 6ppm. I just cant quote that with any qualifications just a memory of something I have read and listening to.
Who has a $3000 reliable DO test equipment probe? and just which part of the wort are you testing? The top, the bottom, the corner, or the entire properly circulated, or SHAKEN thang?

 

[Rocker1986]

I just tip my cubes into the FV from a height and splash it around as much as I can. Works fine for me. Mind you, I do make sufficiently sized yeast starters on a stir plate as well, which probably helps matters...

 

[Danscraftbeer]

I just tip my cubes into the FV from a height and splash it around as much as I can. Works fine for me. Mind you, I do make sufficiently sized yeast starters on a stir plate as well, which probably helps matters...

Fair to say I'd guess you drink good beer.

I'm an advocate for that a wort in a fermenter with a 1/3 headspace, pitched yeast correctly and then sealed
and then shaken for 4 minutes will inoculate and oxygenate all the contents evenly and will make excellent beer.

 

[GalBrew]

Yeah who uses oxygen. That **** is crazy......

It's really not that hard. Get a flow meter and you can work out how much you are pumping in. There is plenty of literature around about how long and at what rates to do this. Much easier than shaking the **** out of 23L of wort for 5 minutes.

 

[Rocker1986]

I don't even shake it :lol:, simply dump cube in and pitch yeast. Seem to get pretty vigorous ferments, they're usually pretty well finished in a few days. Certainly can't complain about the resulting beers anyway.

 

[Danscraftbeer]

I don't even shake it :lol:, simply dump cube in and pitch yeast. Seem to get pretty vigorous ferments, they're usually pretty well finished in a few days. Certainly can't complain about the resulting beers anyway.

Yeah but, you pitch the liquid yeast starter? How big? the whole starter? B)

 

[Ducatiboy stu]

Yeah but, you pitch the liquid yeast starter? How big? the whole starter? B)

24ltr starter for a 22ltr beer.....