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General Category => All Grain Brewing => Topic started by: KellerBrauer on June 30, 2021, 05:23:41 am

Title: Aquarium Pump vs. Pure Oxygen
Post by: KellerBrauer on June 30, 2021, 05:23:41 am
Greetings All - for my entire 8 years of home brewing I have used an aquarium pump to oxygenate my wort.  Now, I decided to use pure oxygen, but have absolutely no idea how to use it.

I bought the regulator and have fitted it to my filter, wand and stone.  So I believe, mechanically, I’m ready to go.

So, now what?  How long do I aerate?  Should I move the stone around the fermentor or set it and leave it?  And, at what flow rate (if there is such a thing) do I dial in the regulator?
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: allenhuerta on June 30, 2021, 05:35:42 am
I just put in the stone, turn on the O2, and watch the bubbles as I move it around for 30 seconds or so.. I don't time it.. I just "count". When one area looks all bubbly, I move it to another spot.

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Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: kpfoleyjr on June 30, 2021, 05:46:50 am
I do much the same as Allen above, with the stone mounted on the end of a wand, tied with tubing to a kegland.com flow meter tie-wrapped to a Bernz-O-Matic red oxygen bottle, set at between 0.2 and 0.5 liters/minute, for 30-45 seconds.
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: KellerBrauer on June 30, 2021, 07:24:52 am
Both good suggestions.  Thanks!

I guess my concern is over-oxygenating - if that' even possible???
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: goose on June 30, 2021, 07:43:03 am
Just to throw another monkey wrench in the works, I don't use pure O2 to aerate wort.  I have a curved piece of copper tubing that has a bunch of holes drilled in it at an angle.  I put this on the end of my transfer hose (with the angled holes facing down) when filling the fermenter and it sucks in air while the beer is going through it (much like Saccromyces does).  It's cheap to make, negates the cost of having a bottle/tank of O2 around, and works just as well for me.  My lag times are relatively short 5-6 hours.
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: MNWayne on June 30, 2021, 08:59:53 am
I used to do O2 for about a minute. Now I just circulate my wort in the SS conical while the cooling coil is doing it's job dropping wort to pitch temp.  Faster cooling while aerating. Two birds, one stone.
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: RC on June 30, 2021, 10:23:49 am
Both good suggestions.  Thanks!

I guess my concern is over-oxygenating - if that' even possible???

For all practical purposes, probably not.

I've always oxygenated 1 min with ale strains, 2 min for lagers, high-gravity worts, or O2-hungry ale strains. Am I doing it correctly? Well, I can't measure how much O2 is dissolving, so I've just let how the beers turn out tell me if I'm on track. After hundreds of batches doing it this way, yes, I am doing it correctly.

You just want a fine mist of bubbles coming from the stone. You're not trying to make the wort look like a hot tub. Any bubbles reaching the surface is wasted, undissolved O2. Gently move the wand around for maximum mixing.

With my last O2 tank (the small red welding kind), I got 155 minutes of oxygenation. That's a lot of batches. YMMV but those tanks last a long time if you don't waste the O2.
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: denny on June 30, 2021, 10:27:28 am
Both good suggestions.  Thanks!

I guess my concern is over-oxygenating - if that' even possible???

For all practical purposes, probably not.

I've always oxygenated 1 min with ale strains, 2 min for lagers, high-gravity worts, or O2-hungry ale strains. Am I doing it correctly? Well, I can't measure how much O2 is dissolving, so I've just let how the beers turn out tell me if I'm on track. After hundreds of batches doing it this way, yes, I am doing it correctly.

You just want a fine mist of bubbles coming from the stone. You're not trying to make the wort look like a hot tub. Any bubbles reaching the surface is wasted, undissolved O2. Gently move the wand around for maximum mixing.

With my last O2 tank (the small red welding kind), I got 155 minutes of oxygenation. That's a lot of batches. YMMV but those tanks last a long time if you don't waste the O2.

Somewhere in the fog of my memory I recall reading that too much O2 can be toxic to yeast.
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: RC on June 30, 2021, 10:49:39 am
Both good suggestions.  Thanks!

I guess my concern is over-oxygenating - if that' even possible???

For all practical purposes, probably not.

I've always oxygenated 1 min with ale strains, 2 min for lagers, high-gravity worts, or O2-hungry ale strains. Am I doing it correctly? Well, I can't measure how much O2 is dissolving, so I've just let how the beers turn out tell me if I'm on track. After hundreds of batches doing it this way, yes, I am doing it correctly.

You just want a fine mist of bubbles coming from the stone. You're not trying to make the wort look like a hot tub. Any bubbles reaching the surface is wasted, undissolved O2. Gently move the wand around for maximum mixing.

With my last O2 tank (the small red welding kind), I got 155 minutes of oxygenation. That's a lot of batches. YMMV but those tanks last a long time if you don't waste the O2.

Somewhere in the fog of my memory I recall reading that too much O2 can be toxic to yeast.

Too much of anything is toxic. But "too much" means different amounts for different molecules and for different organisms. Over-oxygenating by a minute or two will have no impact. Over-oxygenating by 20 minutes is probably bad.
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: Bilsch on June 30, 2021, 03:51:24 pm
I used to do O2 for about a minute. Now I just circulate my wort in the SS conical while the cooling coil is doing it's job dropping wort to pitch temp.  Faster cooling while aerating. Two birds, one stone.

Aerating the wort before it has reached the ferment temp is generally a bad idea. Ideally it should only be done after pitch or very close to pitching.
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: mabrungard on June 30, 2021, 04:22:11 pm

Somewhere in the fog of my memory I recall reading that too much O2 can be toxic to yeast.

I’m not sure that we can achieve O2 toxicity, but I recall Jamil saying he thought that excessive oxygenation results in Fusel production.   I’m fairly reserved when oxygenating for that reason.
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: HopDen on June 30, 2021, 05:51:12 pm
For what its worth, I just let the cooled wort drop from the top of my conical when transferring. When looking into the top of FV the wort is all nice and frothy. I can't tell you how much O2 is added this way but it has been working for me. Short lag times even when using re-pitched yeast. I used to oxygenate and still do on big beers but not so much anymore on others.
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: majorvices on June 30, 2021, 07:47:09 pm

Somewhere in the fog of my memory I recall reading that too much O2 can be toxic to yeast.

I’m not sure that we can achieve O2 toxicity, but I recall Jamil saying he thought that excessive oxygenation results in Fusel production.   I’m fairly reserved when oxygenating for that reason.

Yes by causing accelerated yeast growth.

I think I may have killed a yeast starter with pure o2 one time. Course, I don't know for sure. It was dead AF though
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: chumley on July 01, 2021, 11:51:37 am
FWIW, just barely turn the regulator on enough to get oxygen to flow from the stone. The first couple of times I tried it (and that was 20 years ago), I cranked the regulator open all the way....and found I used an entire small oxygen bottle on two batches. Whoops.
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: majorvices on July 01, 2021, 02:46:42 pm
+1 -- I can get 6-10 batches off one tank
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: Visor on July 01, 2021, 03:03:28 pm
  I have a 5# bottle, regulator and a 0.5 micron stone, set the regulator at 0.5 lpm and give it 60 seconds. At that rate IIRC I got a couple hundred batches out of the 1st bottle. I also have read somewhere [maybe Palmer?] that pure O2 can kill yeast, at least under the wrong circumstances. As with yeast nutrient I figure it's cheap insurance.
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: RC on July 01, 2021, 04:07:59 pm
+1 -- I can get 6-10 batches off one tank

I get about 110 batches off one tank. Obviously we're oxygenating very differently. I wish it was feasible to test how much oxygen is being added...
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: RC on July 01, 2021, 05:50:52 pm
Aerating the wort before it has reached the ferment temp is generally a bad idea. Ideally it should only be done after pitch or very close to pitching.

I agree with this. Otherwise the oxygen is doing something else in the wort, regardless of what that something else might be.
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: RC on July 01, 2021, 06:02:24 pm
We're now in the realm of (possible) brewing mythology. "I heard this somewhere...I read this somewhere...I recall this...I recall that...from this or that brewer/homebrewer..." etc. Anecdotes passed down from "experts."

Is there credible, peer-reviewed, real-world-applicable literature on this, from actual brewing scientists, re: brewing strains of S. cerevisiae specifically? Talk to me, Dr. Bamforth.

I'll add my own anecdote: I've likely over-oxygenated quite a bit. I now even oxygenate my 1-liter starters with the O2 tank and wand. Never had an issue with yeast performance or, most importantly, the final product. But the plural of anecdote is not "data". Reactive Oxygen Species (ROS) is definitely a thing for all aerobes on this planet. But I'm not sure they have affected my beer yet.

If too much oxygen (within reason; see my previous comment) is toxic to brewing yeast, I feel like I would know by now. Could this be yet another brewing myth?
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: jjflash on July 01, 2021, 08:59:41 pm
For low gravity beer less than 1.060 simple aeration provides ample oxygenation.
For high gravity beer I use 1 PPM per degree Plato oxygen.
Without a good DO (dissolved oxygen) meter it is impossible to tell how much oxygen you are putting in.
As a friend once told me, it is like turning on the shower and telling me to turn it off at 16 gallons - near impossible.
For most of us we used trial and error method  - 10 minutes and beer okay, next time lets try 5 minutes and see if still good, then 2 minutes.....
I have use high quality DO meter for years.
The amount of oxygen actually getting into the wort I discovered can be quite variable depending upon technique.
The good news is, early on I also discovered oxygen readily diffuses out of the wort.
So if you shoot too in much oxygen, over oxygenated, it just comes right out of solution within a short time.
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: mabrungard on July 02, 2021, 07:31:20 am
+1 -- I can get 6-10 batches off one tank

I get about 110 batches off one tank. Obviously we're oxygenating very differently. I wish it was feasible to test how much oxygen is being added...

I'm not sure that I get that many batches out of a red bottle, but it has proven to be a lot of batches.  If you can see bubbles at the surface of your wort, your O2 flow rate is too high or the diffuser isn't deep enough.  Anything escaping the wort is wasted.  It takes a low flow rate and longer duration to properly use O2.  Blasting...is wasting.   
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: narcout on July 02, 2021, 08:50:34 am
We're now in the realm of (possible) brewing mythology. "I heard this somewhere...I read this somewhere...I recall this...I recall that...from this or that brewer/homebrewer..." etc. Anecdotes passed down from "experts."

Is there credible, peer-reviewed, real-world-applicable literature on this, from actual brewing scientists, re: brewing strains of S. cerevisiae specifically? Talk to me, Dr. Bamforth.

Below are links to two articles that have been previously been posted on this forum by other members.  I expect there are many more out there (and I think this is probably true regarding most of the technical questions that come up here; we have access to so much professional literature these days).

The effect of wort aeration on fermentation, maturation and volatile components of beer produced on an industrial scale: https://onlinelibrary.wiley.com/doi/full/10.1002/jib.392

Oxygen in brewery fermentation:
https://onlinelibrary.wiley.com/doi/pdf/10.1002/j.2050-0416.1974.tb03614.x
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: denny on July 02, 2021, 09:38:33 am
We're now in the realm of (possible) brewing mythology. "I heard this somewhere...I read this somewhere...I recall this...I recall that...from this or that brewer/homebrewer..." etc. Anecdotes passed down from "experts."

Is there credible, peer-reviewed, real-world-applicable literature on this, from actual brewing scientists, re: brewing strains of S. cerevisiae specifically? Talk to me, Dr. Bamforth.

I'll add my own anecdote: I've likely over-oxygenated quite a bit. I now even oxygenate my 1-liter starters with the O2 tank and wand. Never had an issue with yeast performance or, most importantly, the final product. But the plural of anecdote is not "data". Reactive Oxygen Species (ROS) is definitely a thing for all aerobes on this planet. But I'm not sure they have affected my beer yet.

If too much oxygen (within reason; see my previous comment) is toxic to brewing yeast, I feel like I would know by now. Could this be yet another brewing myth?

Now?  What do you mean "now"?
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: majorvices on July 02, 2021, 09:38:52 am
+1 -- I can get 6-10 batches off one tank

I get about 110 batches off one tank. Obviously we're oxygenating very differently. I wish it was feasible to test how much oxygen is being added...

Off on one of those little red welding tanks? I should go back and clarify that I can get 6-10 batches but that was based off of when I did 12 gallon batches many years ago. Now I'm doing about 6 gallon and also 5L and I've had the same red tank for a pretty long time ... no idea how many batches. But I find it nearly impossible to believe that you re using the little red welding o2 tanks and getting over 110 batches.
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: RC on July 02, 2021, 10:01:26 am
+1 -- I can get 6-10 batches off one tank

I get about 110 batches off one tank. Obviously we're oxygenating very differently. I wish it was feasible to test how much oxygen is being added...

Off on one of those little red welding tanks? I should go back and clarify that I can get 6-10 batches but that was based off of when I did 12 gallon batches many years ago. Now I'm doing about 6 gallon and also 5L and I've had the same red tank for a pretty long time ... no idea how many batches. But I find it nearly impossible to believe that you re using the little red welding o2 tanks and getting over 110 batches.

Yes, same bottles. As I wrote in my earlier comment, with my last bottle I got 155 minutes of aeration (I put a tick mark on the bottle for each minute). Most of my brews are ales, which get 1 min. My lagers get 2 min. 110 batches is an estimate, but it's close.

Again, you just want a fine mist of bubbles coming from the stone. That way most of it dissolves. If you see froth on the surface of your wort, that's wasted oxygen.

I'm obviously using a heck of a lot less oxygen than you. My guess is you're still getting adequate oxygen dissolved into you wort, but with a lot of wasted oxygen as well.

EDIT: I recounted the tick marks. I got 147 minutes from the bottle, not 155. Still in the neighborhood of 100 batches.
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: majorvices on July 02, 2021, 11:28:10 am
Wow. That's amazing. I only use a fine mist of bubbles so I'm still surprised. I saw another thread someone managed to hood a flow meter up to those red bottles. That would be a good start of understanding "how much" is added. But of course, without a DO meter it's just a good guess.
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: RC on July 02, 2021, 11:59:25 am
Wow. That's amazing. I only use a fine mist of bubbles so I'm still surprised. I saw another thread someone managed to hood a flow meter up to those red bottles. That would be a good start of understanding "how much" is added. But of course, without a DO meter it's just a good guess.
Maybe I have a smaller-sized aeration stone? The one I use is 1" long by about 3/8" diameter.
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: chumley on July 03, 2021, 04:48:57 pm
I am definitely in the camp of majorvices on how many uses I get out of those little red disposable oxygen tanks. Over a hundred uses is mind boggling. Maybe I need to use less. I have had well attenuated beer for years now, though, since I started using those, so I am hesitant to mess with success, as I can afford those pricy little tanks.
Title: Re: Aquarium Pump vs. Pure Oxygen
Post by: BrewNerd on August 22, 2021, 08:57:10 am
I consulted my library (pile of beer books threatening to snap my shelf in half) and found the following:

Palmer used an aquarium pump with an in-line HEPA filter to oxygenate (How to Brew 4th ed. page 97) Avoids the dangers of over oxygenating when you're using normal air.

He also follows Jamil's thought process of getting off flavors when using too much straight O2.

No mention of needing a filter on an O2 bottle.