Putting this out there as I am not able to find any definite direction so far. I have evolved my brewing technique from making lots of splashing into my fermenter as I cooled my wort to collecting all cooled wort in the fermenter then inserting an air stone with pure O2 for a minute to make happier yeast. now I am looking at an inline setup as my wort passes from the chiller to the fermenter but I am thinking that using pure O2 would over oxygenate and a fish pump with a heppa filter would be best with a flow meter regulating anywhere from half to 1 litre per minute of air. Can anyone offer their experiences please and thank you.
Oxygenate v aerate
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On homebrew scale, with our relatively small batch sizes, keep it simple and dose with pure O2 right before pitching yeast as you're doing now. Nothing wrong with that.
Injecting O2 inline is way more complicated, hard to control exact dosage, depending on wort flow, etc. For commercial breweries, sticking a wand with an O2 stone in a 5 to 5000 barrel fermentor is impractical, so inline is the better solution. They also have the equipment to monitor that.
Injecting O2 inline is way more complicated, hard to control exact dosage, depending on wort flow, etc. For commercial breweries, sticking a wand with an O2 stone in a 5 to 5000 barrel fermentor is impractical, so inline is the better solution. They also have the equipment to monitor that.
Thanks but not sure that's the best solution. I have heard others doing the way I mentioned but without a flow meter to regulate the air from a fish pump. Seems way better saturation than using the wand and O2. Pure at best is still not pure and we are only looking for 8 - 10 ppm O2. Most of the O2 using a wand seems to just bubble off and not saturate. May be a waste of the $8 per cylinder as I don't notice a big difference from the splashing in method I used to do. Just looking to control and have repetitive consistancies.
SpeedYellow
Well-Known Member
Fish pump is fine, if you don't mind waiting 20 minutes to aerate your wort. I did that for years. But O2 only takes 60 sec., which is reason enough for me!
Dcpcooks
Well-Known Member
10 ppm is your goal.
A stone and a pump will get you to 8 ppm on the high side.
Pure 02 with a regulator set at 1 liter per min through a .5 micron stone running for 1 min into 5 gallons of wort will yield 10 ppm of dissolved o2.
You can add too much pure o2. The best way to manage that is by being able to set your regulator for 1 liter per min. Without an accurate form of measuring the flow rate your guessing.
That data is from the book Yeast by White of white labs.
A stone and a pump will get you to 8 ppm on the high side.
Pure 02 with a regulator set at 1 liter per min through a .5 micron stone running for 1 min into 5 gallons of wort will yield 10 ppm of dissolved o2.
You can add too much pure o2. The best way to manage that is by being able to set your regulator for 1 liter per min. Without an accurate form of measuring the flow rate your guessing.
That data is from the book Yeast by White of white labs.
Agreed that any rippling/bubbling on the surface is O2 that was not absorbed by the wort.
With 5.5 - 6 gallons of wort in a 6.5 gallon bucket, I see a quite a bit of bubbling/rippling/foaming on the surface using a .5 micron stone on the bottom at 1 l/m. So I'm not sure why that's recommended, looks like a waste.
After observing that, I've dialed back by oxygenating at 1/4 l/m for 4 minutes, and am happy with the results. I could go as low as 1/32 l/m, for say 16 minutes, showing hardly any surface rippling, still some foaming, but that sure sounds overkill.
Someone gave me a spreadsheet for estimating dissolved O2. The 1 l/m for 1 minute looks in line with 8-10 ppm, but without a DO meter it's hard to verify. The amount of rippling on the surface made me lower the rate and extend the duration accordingly. The depth of the vessel and movement across the bottom surface plays a role, undoubtedly.
I agree but the DO meter is pricy but I also found that a flow meter set at 0.5 - 1 l/min with an inline air stone will give similar results. I was just looking to see is anyone has tried this yet and what the outcome was.
That dosage sounds extremely high using O2, if it takes you 25 minutes to run 10-15 gallons off to the fermentor. But it maybe right using air. The maximum you can achieve with air is around 8 ppm, keep that in mind.
I have the feeling the batch size can be fairly large, say 15 gallons, to still get adequate oxygenation when sticking a wand with a stone into the fermentor and run O2 for 1 minute at 1 l/m. IOW, no less than doing the same in a 5 gallon batch, which may assimilate as much per minute as the 15 gallon batch does, just with more waste, witnessed by more rippling/bubbles on the surface.
DogFishHead runs their wort from the chiller through their yeast chamber where the proper yeast and oxygen are concurrently added/injected into the wort stream on her way to one of the 18,000 gallon fermentors outside. They need to brew 3 times to fill one of those. I'm sure they know precisely how much of each is being added per second/minute. Don't want to screw up a batch like those.
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Dcpcooks
Well-Known Member
Page 81.
I confess, I mis-remembered the details. It was actually 35.8 ppm - still pretty darned high by any measure - and it wasn't a test so much as it was relating a survey of oxygenation results at various breweries.
My presumptions are from earlier in the book where White implies there doesn't seem to be a down-side to higher oxygenation levels, along with the assumption that the particular brewery hitting 35.8 ppm must be making decent enough beer to survive...
Cheers!
I'm doing 10gal batches using pure O2 via a Blichmann regulator @ .5L/min and 7' of hose to the conical. Yeast is very happy with vigorous fermentation (multiple generations) and zero off flavors. Maybe a bit more in capital outlay, but very consistent beer both ales and lagers. Big boys have dissolved O2 sensors to keep O2 cost down.
Ok, so the point is I just purchased a flow meter and have an inline airstone from the chiller to fermenter. I also have been using pure O2 in the past using a wand not inline but sticking the thing into the triclamp hole in the lid but the wand is not long enough to go to the bottom and I don't see a good O2 saturation potential which is why I am switching to the inline style but being more efficient I was/am worried about over oxygenating. If I use the flow meter at .5 lpm then are you saying I will not over oxygenate with pure O2?
You should be fine for most of your brews with that setting. If you go with a big brew, like a barley wine, then you might bump it up to 1L. There are so many variables that impact the O2 (Wort temp, Wort flow rate, microns on stone, length of tubing) that unless you have a way to measure dissolved O2 it is a guess. Better slightly over than under for the happiest and strongest yeast.
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