How do you know when you've added enough oxygen?

I don't have a dissolved O2 meter.
I have the Williams aeration system (no flow gauge).


Instructions say to aerate for 1 minute, but it doesn't say what the flow should be set it.

I know that I don't want tons of bubbles breaking the surface because that means I'm wasting oxygen. I've noticed the faster I swirl the wand around while aerating, the higher flow rate I can get away with-without breaking the surface---BUT the surface starts to bubble and foam up. Is that a good thing or a bad thing?

With no gauge/meter on that regulator, I had the same question. I also found it went from zero to full with nothing between. Not what I wanted. So I changed over to a regulator with a flow meter and a welding O2 tank (smallest you can get). Now I KNOW how much O2 I'm pushing into the wort. Next step, for me (after xmas) is to get a dissolved O2 meter so that I can start testing the wort after oxygenating it. I plan to build up either a spreadsheet or database of the O2 flow rates, time, and dissolved O2 readings.

30 seconds for normal beers and a minute for anything over 1.070. Set the flow rate to just more than open. The flow rate does change with this o2 kit, its not just full blast, at least mine does it like this.

http://***********/stories/wizard/a...xygen-canisters-safe-for-homebrewing-aeration

An article with some formulas for figuring out how much o2 you need

Except it doesn't go into any details as to figure out how much O2 is actually needed for your batch. It assumes that 8ppm is what you need, but doesn't factor in the OG of the batch and how it can actually have difficulty taking O2 into solution. I believe the Yeast book goes into it better (and is newer).

Also, good luck finding an O2 regulator flow meter that has that fine of graduations or doesn't go to 4LpM or above for it's top end. Many go to either 8LpM or 15LpM. Plus, the Yeast book outlines how if you do infuse more O2 than the yeast needs, by the time the get around to using it (for most people) a good amount has already escaped from the wort.

Personally, I've not had any negative effects from using higher LpM numbers (typically 1-1.5LpM for moderate OG batches, running for 60-90 seconds through the 2 micron stone).

I just got yeast from the library and studies it has in it basically say 9ppm and 14ppm end up at the same place. It is really hard to over oxygenate.

I think its too costly to measure dissolved oxygen, the book says most breweries don't.

Better to have more than not enough.

I've actually got my eye on this dissolved O2 meter. Probably going to order it up after the holiday. Prices on the units have been slowly coming down over the past 6-12 months since I started looking. So it's almost to the point where I can stomach the cost. It will be easier if I sell a lens I'm not using, or maybe that spare tripod I really don't need. Either one will sell for more than that meter (the lens is worth about 25x what the meter costs, the tripod about 4x).

You can shake the fermenter to dissolve more oxygen after you have used the wand. It's just like you used to do it only the headspace is filled with more oxygen.

I whip the wort with a wire whisk until my arm gets tired and then pitch the yeast

Seriously, is there real or persieved value in using pure O2 vs. a method as I use?

Toy4Rick

Toy4Rick said:

I whip the wort with a wire whisk until my arm gets tired and then pitch the yeast

Seriously, is there real or persieved value in using pure O2 vs. a method as I use?

Toy4Rick

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Once you need more than 8ppm of O2 there is, in a big way. You'll never get more than 8ppm O2 in the wort no matter how long, or hard, you whip it (even if you whip it good). Brew something of higher OG, where more than 8ppm is needed/wanted, and you're not going to be able to provide it with the whip method (or any using atmospheric O2 concentrations).

Brew a bigger beer where it's advisable to oxygenate it again after 12-18 hours and you'll have more issues with the whip method. Not so with a pure O2 infusion via an air stone.

Golddiggie said:

Once you need more than 8ppm of O2 there is, in a big way. You'll never get more than 8ppm O2 in the wort no matter how long, or hard, you whip it (even if you whip it good). Brew something of higher OG, where more than 8ppm is needed/wanted, and you're not going to be able to provide it with the whip method (or any using atmospheric O2 concentrations).

Brew a bigger beer where it's advisable to oxygenate it again after 12-18 hours and you'll have more issues with the whip method. Not so with a pure O2 infusion via an air stone.

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What if you use a paint mixing paddle? I'd believe 8ppm is possible in heavier beers with that.

DurtyChemist said:

What if you use a paint mixing paddle? I'd believe 8ppm is possible in heavier beers with that.

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8ppm is the absolute maximum O2 level you can reach without going to pure O2. Doesn't matter what method you use, or for how long. Bigger beers NEED more O2 in order for the yeast to have better health, replicate better and otherwise do a better job. IMO if you're taking the time to brew something big, spend the funds to use pure O2 to oxygenate properly. It baffles me that people continue to cut corners with such things and then post up wondering why things aren't going well.

I'm not sure if it's the only place that the 8ppm number came from, but I know there's a YouTube video of Greg Doss from wyeast saying that's the absolute best you can do. On the other hand I think it was on a bn episode where Chris White from white labs reported that he didn't think you could get much better than 3 or 4. He joked that Greg was a pretty big guy so maybe he could do better.

One minute 30 seconds at a slow rate is good. Blasting the o2 only causes the o2 to escape into the headspace (which you could then shake to dissolve into the wort as MTB mentioned). With the slow method I was getting 7 to 9 ppm measurements with my dissolved oxygen meter.

The 8ppm limit is God's way of telling you that beer shouldn't be over 1.070.

My book here says observed o2 levels at one if the yeast labs were 3ppm for 5 min of shaking, 5ppm for 30 seconds of o2, 9ppm for 1 minute, and 14ppm for 90 seconds.

BetterSense said:

The 8ppm limit is God's way of telling you that beer shouldn't be over 1.070.

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F that.. I never listen to that junk anyway. :rockin:

theveganbrewer said:

My book here says observed o2 levels at one if the yeast labs were 3ppm for 5 min of shaking, 5ppm for 30 seconds of o2, 9ppm for 1 minute, and 14ppm for 90 seconds.

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Book and page number? Keep in mind, different OG worts will take O2 differently. A low OG wort will be easier to infuse than a higher OG wort.

From the yeast book, 1.077 OG, 20 liter sample. 1 liter per minute flow on the o2 tank with a 5 micron stone. Test done by White Labs.

theveganbrewer said:

From the yeast book, 1.077 OG, 20 liter sample. 1 liter per minute flow on the o2 tank with a 5 micron stone. Test done by White Labs.

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Sounded familiar, just didn't want to dig through the book... I wish they had more charts/examples of the O2 levels and what's actually needed for the yeast in such examples. Especially since O2 absorption in the wort is dependent on the OG. So, a wort with an OG of 1.045 will absorb differently than the OG of 1.077 and differently than an OG of 1.120. Unless someone knows of a chart/table that gives the O2 infusion rates and dissolved O2 levels that resulted. As well as how much O2 the yeast needs in those worts.

I am a perfectionist but i m having a hard time figuring out why I'd need to be more precise than the 1 minute for 1.050 and adjust from there. There seems to be a lot of leeway up above 8ppm, not worth stressing unless evidence is given higher 02 effects taste. Everything I've read is that between 1-2 minutes you'll be good.

Mr. Wizard, in the BYO article, has it spot on. Also, From "The Practical Brewer" Yeast - Strains and Handling Techniques, Yeast Growth

Too much oxygen results in too much yeast growth, with excessive nutrient loss to cellular reproduction instead of ethanol production

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8-9ppm is the maximum saturation with air. If sugar is dissolved in the wort then not as much oxygen can dissolve, however the limit is minimal unless the sugar level is on the same order of magnitude of the saturation point. This is near 1.200.

50ppm is possible with O2. 1ppm per degree Plato is the recommended oxygenation rate to match the cell division needed with a standard ale pitch rate. (Blog post on this coming in a few weeks putting all this information together)

Golddiggie said:

.... you whip it (even if you whip it good).

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I see what you did there.

theveganbrewer said:

I am a perfectionist but i m having a hard time figuring out why I'd need to be more precise than the 1 minute for 1.050 and adjust from there. There seems to be a lot of leeway up above 8ppm, not worth stressing unless evidence is given higher 02 effects taste. Everything I've read is that between 1-2 minutes you'll be good.

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There's a thread around here from a while back where batches were brewed where pure O2 was used, as well as other aeration/oxygenation methods. The parts that were infused with O2 were better in the glass. Improved flavors, or more desirable flavors into the glass, as well as reduced time post fermentation (to reduce/eliminate off flavors) were also reported (if I recall correctly). In my own case, less work/street to get the O2 into the wort is enough benefit to keep me doing it.

WoodlandBrew said:

Mr. Wizard, in the BYO article, has it spot on. Also, From "The Practical Brewer" Yeast - Strains and Handling Techniques, Yeast Growth

8-9ppm is the maximum saturation with air. If sugar is dissolved in the wort then not as much oxygen can dissolve, however the limit is minimal unless the sugar level is on the same order of magnitude of the saturation point. This is near 1.200.

50ppm is possible with O2. 1ppm per degree Plato is the recommended oxygenation rate to match the cell division needed with a standard ale pitch rate. (Blog post on this coming in a few weeks putting all this information together)

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Hoping to see information that can be used to help figure out how much, and for how long, I really should be infusing for. I highly suspect the infusion rates are not linear for higher OG worts. Such as it's not for making starters, and such. So while the 1ppm per degree Plato could be a good base, I suspect that you cannot use a linear flow rate and time formula to get what you need for different OG worts.

Evan_L said:

I see what you did there.

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Wasn't hiding anything... You just need to be old enough to actually get the reference.