Author Topic: Opinions on aeration system  (Read 2049 times)

Offline narvin

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Re: Opinions on aeration system
« Reply #15 on: July 07, 2011, 12:43:09 PM »
As lagers become more of my brewing portfolio, one soon realizes that O2 will get you to the 10-12 ppm often quoted that you need for lager yeast.  Using air you can only get to about 8 ppm.

FWIW, the saturation point at 50°F is ~12 ppm, so if you're chilling before aerating you can also get to the recommended levels for a lager.

Sean,
I'm not disagreeing with you, but I've read elsewhere that "too much oxygenation of the wort can be detrimental to yeast."  
How is this possible if the saturation point at 50°F is ~12 ppm?

That's the saturation point using air, not O2.  He's saying that you can get to 12 ppm using only air if you chill the wort first since the solubility increases.
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Offline tschmidlin

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Re: Opinions on aeration system
« Reply #16 on: July 07, 2011, 12:54:49 PM »
As lagers become more of my brewing portfolio, one soon realizes that O2 will get you to the 10-12 ppm often quoted that you need for lager yeast.  Using air you can only get to about 8 ppm.

FWIW, the saturation point at 50°F is ~12 ppm, so if you're chilling before aerating you can also get to the recommended levels for a lager.

Sean,
I'm not disagreeing with you, but I've read elsewhere that "too much oxygenation of the wort can be detrimental to yeast." 
How is this possible if the saturation point at 50°F is ~12 ppm?
Because what you read is technically true but taken out of context.  You can't saturate the wort with enough O2 to harm your yeast.  If you constantly use O2 while growing your yeast you may overwhelm their metabolism and cause damage.  Since we don't constantly pump in O2 it is not an issue.
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Offline narvin

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Re: Opinions on aeration system
« Reply #17 on: July 07, 2011, 01:22:57 PM »
As lagers become more of my brewing portfolio, one soon realizes that O2 will get you to the 10-12 ppm often quoted that you need for lager yeast.  Using air you can only get to about 8 ppm.

FWIW, the saturation point at 50°F is ~12 ppm, so if you're chilling before aerating you can also get to the recommended levels for a lager.

Sean,
I'm not disagreeing with you, but I've read elsewhere that "too much oxygenation of the wort can be detrimental to yeast." 
How is this possible if the saturation point at 50°F is ~12 ppm?
Because what you read is technically true but taken out of context.  You can't saturate the wort with enough O2 to harm your yeast.  If you constantly use O2 while growing your yeast you may overwhelm their metabolism and cause damage.  Since we don't constantly pump in O2 it is not an issue.

I don't know...  you can theoretically get to 40+ ppm with pure O2, and I have heard that there's the possibility of oxygen toxicity.  In practice I'd be much more worried about affecting the flavor profile than harming the yeast.  Pitching rate, temperature, and aeration are all factors that affect the flavor of the final beer, and adjusting any one will change the result.  I would be very careful about using too much oxygen in any beer that is supposed to derive a lot of character from the yeast.
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Chris S.

Offline Joe Sr.

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Re: Opinions on aeration system
« Reply #18 on: July 07, 2011, 01:26:04 PM »
Also are the regulators for dissposable O2 available from HD? Then I could just get the .5 from morebeer and get the regulator at HD avoiding two shipping costs.

I'd be interested in knowing this also.  It looks like they are essentially the same thing you would get using a mapp gas torch, or a brazing torch kit.

Is that accurate?  If so, I pretty much have what I need to move from my aquarium pump to disposable oxygen bottles.
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Offline ukolowiczd

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Re: Opinions on aeration system
« Reply #19 on: July 07, 2011, 02:04:36 PM »
I love my O2 wand system from Williams Brewing: http://www.williamsbrewing.com/WILLIAMS-OXYGEN-AERATION-SYSTEM-P699.aspx. Ok, it may be $50 (maybe you could find cheaper?) and O2 tanks are around $8 for about 5-7, 5 gallon brews but I oxygenate for 45 seconds - let me repeat that - 45 seconds and I'm done! No shaking the thing for 10 minutes or waiting for an aquarium pump to oxygenate the wort. My fermentation start times have been considerably quicker and I get far, far more attenuation especially with my Belgian strains. And I have never, ever had any negative effects like no/low fermentation or off flavors, so I think that might just be a rumor.   

Offline tschmidlin

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Re: Opinions on aeration system
« Reply #20 on: July 07, 2011, 03:27:57 PM »
I don't know...  you can theoretically get to 40+ ppm with pure O2, and I have heard that there's the possibility of oxygen toxicity.  In practice I'd be much more worried about affecting the flavor profile than harming the yeast.  Pitching rate, temperature, and aeration are all factors that affect the flavor of the final beer, and adjusting any one will change the result.  I would be very careful about using too much oxygen in any beer that is supposed to derive a lot of character from the yeast.
Oxygen toxicity exists, it is just not an important consideration for homebrewers.  Even at 40+ ppm, that level will start dropping within minutes of adding the yeast.  RDWHAHB

As for it affecting the flavor profile of the finished beer, like you pointed out it is just one of the things you can manipulate to get the flavor profile you want.
Tom Schmidlin

Offline narvin

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Re: Opinions on aeration system
« Reply #21 on: July 07, 2011, 03:55:02 PM »
As for it affecting the flavor profile of the finished beer, like you pointed out it is just one of the things you can manipulate to get the flavor profile you want.

Definitely, as long as you can adjust it in a reproducible way.

I'm just cautiously pointing out that more oxygen may not always be better.  More is different, and for your hefeweizen, more may be worse  :)
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Chris S.