How Long to Oxygenate wort?

[Rickcobba]

Hi All,

Can anyone help me calculate how long i need to Oxygenate my wort and at what psi? Using an oxygen cylinder and 5mm ID line, and wanting to achieve approx 15ppm.

Are there specific formulas to use to get exact results?

 

[Cervantes]

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.

 

[Yob]

Why 15ppm? Isn't 12 the magic number you don't want to go over?

 

[ebyelyakov]

I believe 15 would be the max for high gravity wort.. 1 minute with pure oxygen.

I use airpump. Since Jamil, Ashton and other experts say it is impossible to overoxygenate with the pum, I usually leave it overnight after pitching the yeast... Pleased with results -- largers kick in after about 10-15 hrs (I use starters and ensure my pitch rates are what I want them to be).

 

[bshb]

as far as i've read 15ppm is too high, 8-10ppm is recommended, if you are brewing a high gravity beer then you're better off introducing o2 again after 12 hours (one cell division).

given that there are a lot of factors that will effect o2 take up i haven't come across a specific formula but i did come across this..

taken from 'brewing elements series - yeast' addition: white labs ran an experiment that showed pure o2 into 20L (24°C) of 1.077 wort with a 0.5 stainless sintered stone at a flow rate of 1L per minute for 60 seconds = 9.2 ppm which is what you want.

 

[Mattwa]

This may be of some interest. Not conclusive, but interesting all the same:

http://brulosophy.com/2015/05/25/wort-aeration-pt-1-shaken-vs-nothing-exbeeriment-results/

 

[ebyelyakov]

A matter of opinion and experiement I guess.
BYO had slighltyl different view on the topic:
http://byo.com/hops/item/1882-fermenting-high-gravity-beers-techniques

For wort of 15 °Plato (specific gravity of 1.061) fifteen minutes of air or two minutes of oxygen should be sufficient.

For wort of 20 °Plato (specific gravity 1.083) or more, aerate up to an hour with air, or ten minutes with oxygen to be sure oxygen is not lacking for the yeast to grow.

I personally believe that 10 minutes of pure oxygen is heaps over the tops.. However, since most of pundits agree it is impossible to go over with the air, that's what I do -- just pump it for a bit longer.

 

[Black n Tan]

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.

 

[razz]

I use 10 gms per 42 lt batch, set the cylinder on a small kitchen scale. I did work it out a few years ago how many ppm it works out to. Although I didn't take into account the SG, temp etc.

 

[Rickcobba]

Thanks for all your input guys!

Its for 45L of RIS with an OG of 1.098
I read somewhere to use around 15 ppm.

Ive seen L/min mentioned, how would you convert psi to L/min?

 

[Rickcobba]

as far as i've read 15ppm is too high, 8-10ppm is recommended, if you are brewing a high gravity beer then you're better off introducing o2 again after 12 hours (one cell division).

given that there are a lot of factors that will effect o2 take up i haven't come across a specific formula but i did come across this..

taken from 'brewing elements series - yeast' addition: white labs ran an experiment that showed pure o2 into 20L (24°C) of 1.077 wort with a 0.5 stainless sintered stone at a flow rate of 1L per minute for 60 seconds = 9.2 ppm which is what you want.

yeah thats what im after. But an equation that you can change the variables to suit.

 

[TheWiggman]

I'm more interested in how you'll know if you've achieved a certain PPM of O2 in wort.

PPM = parts per million
l/min is rate of volume
psi = pounds per square inch, pressure

None of the above units have anything to do with one another. As Black n Tan said the maximum you can achieve is around 10 PPM. He also gave the flow rates. So by extension if you want to get the maximum PPM of O2 in solution using pure O2 for 40 litres of 1.098 SG you'd want 1l/min for 5 mins. Pressure is irrelevant, total delivery is what you're after so flow rate and time is all you need.

 

[Black n Tan]

If you can't monitor flow rate, then you can just set the pressure such that you can just see oxygen bubble hitting the surface and do that for 4-5 minutes for 45L batch. That will get you close and you can adjust next time if you don't like the results. Of course I assume you have a sinter stone to deliver the oxygen, otherwise you will have to go much longer. I place the sinter stone at the bottom of the fermenter and then gently stir as i deliver the oxygen to ensure as much oxygen is dissolved as possible. Alternatively you could weigh the bottle as someone has suggested: 4L of oxygen will weigh about 5.7 grams, but you would want some pretty good scales.

 

[Ducatiboy stu]

Does it really help to oxygenate your wort......


What are the end results....

 

[BobtheBrewer]

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.

What type of oxygen supply do you have and where did you get it from?
Bob

 

[Rickcobba]

I'm more interested in how you'll know if you've achieved a certain PPM of O2 in wort.

PPM = parts per million
l/min is rate of volume
psi = pounds per square inch, pressure

None of the above units have anything to do with one another. As Black n Tan said the maximum you can achieve is around 10 PPM. He also gave the flow rates. So by extension if you want to get the maximum PPM of O2 in solution using pure O2 for 40 litres of 1.098 SG you'd want 1l/min for 5 mins. Pressure is irrelevant, total delivery is what you're after so flow rate and time is all you need.

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.
Also Black n Tan stated that for OGs of 1.10 and over he uses 1L/min for 2.5mins. My og is 1.098, how did you get 5 mins?
And as for knowing what the ppm will be, I dont. And thats why im asking the question.

 

[TheWiggman]

Does it really help to oxygenate your wort......


What are the end results....

Apart from the scientific evidence posted through the site from credible sources (MHB, Martin, DrSmurto etc)? Speeds up fermentation time and attenuates consistently. Has done wonders in my case particularly on the starter plate, get much more action and a larger volume of yeast. Since doing it I haven't had any stuck ferments or unexpectedly high finishes.
Though it's a bit like hydrate vs. dry pitch, at the end of the day you'll get beer and that's all I'm going to say about that h34r:

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.
Also Black n Tan stated that for OGs of 1.10 and over he uses 1L/min for 2.5mins. My og is 1.098, how did you get 5 mins?
And as for knowing what the ppm will be, I dont. And thats why im asking the question.

As BnT said, watch for bubbles on the surface. A pressure gauge won't give you an indication of flow rate in this case.
I got 5 mins because you said 40 litres. I assumed BnT did standard 23l batches. More wort = more oxygen required for same PPM in solution.

 

[MaltyHops]

how do you know what psi will give you a flow rate of 1L/min.

Basically you cannot measure flow rate using pressure. You could have the O2 valve shut, opened to have a very small flow, opened to have a high flow - and it will still all be at the same pressure (assume the bottle is not near empty). Need a flow meter.

Also Black n Tan stated that for OGs of 1.10 and over he uses 1L/min for 2.5mins. My og is 1.098, how did you get 5 mins?
And as for knowing what the ppm will be, I dont. And thats why im asking the question.

Could just use the try-and-see-what-happens approach - start with above recommendations and see how well it goes, add more or less next time.

 

[Black n Tan]

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.
Also Black n Tan stated that for OGs of 1.10 and over he uses 1L/min for 2.5mins. My og is 1.098, how did you get 5 mins?
And as for knowing what the ppm will be, I dont. And thats why im asking the question.

My advice was for a standard 21-23L batch, so for your larger batch go for 4-5 minutes with the oxygen just breaking the surface. I typically do 40-off litres also but gave advice for a standard batch.

 

[Ducatiboy stu]

, at the end of the day you'll get beer and that's all I'm going to say about that h34r:

B)