How much oxygen do I need to put into my wort?

I've heard that homebrewers need to aerate with an oxygen stone and either aquarium pumps or oxygen. Is this true, or is shaking my carboy enough to get proper oxygenation?

  • How much oxygen is needed? Does it vary based on the wort?
  • How effective are the various methods?
  • possible duplicate of Wort aeration on a budget
    – Nick
    Nov 27, 2010 at 22:11
  • 2
    Maybe, but I'm not concerned about pinching pennies, but rather, wanted a more comprehensive answer. That question doesn't actually address the amount of oxygen needed, just how to cheaply get it into wort.
    – Brandon
    Nov 28, 2010 at 0:45

4 Answers 4


So it turns out:

The proper amount of oxygen dissolved in wort is 8-10 ppm.

Shaking typically yields around 4 ppm. It's possible to achieve as much as 8 ppm with plenty of headspace and LOTS of vigorous shaking. As an example, 5 minutes of shaking a 1.077 wort may only achieve 2.7 ppm. Siphon sprayers will be in the same range.

Air with an Oxygen Stone can also only reach 8 ppm, regardless of the amount of time the stone is in the wort.

Oxygen with an Oxygen Stone Using a .5-micron stone and a flow rate of 1 L O2 / min, you need around 60 seconds to get 9 ppm, as shown:

30 seconds pure O2          5.12 ppm
60 seconds pure O2          9.20 ppm
120 seconds pure O2        14.08 ppm

When oxygenating a higher-gravity wort, you need higher oxygen levels - roughly proportionate to the amount of yeast. However, it's usually recommended to reoxygenate after the yeast have time for a cell division, This will result in a cleaner-flavored beer. Obviously, if you want your beer to have more off-flavors (specifically acetaldehyde and diacetyl), then a second dose of oxygen is counter productive.

Looks like I need to make a trip to the pet store...

EDIT: Keep in mind these values are also temperature dependent. The cooler the wort is, the better your ppm aeration will be in the end.

  • Great question and great answer. Hope you don't mind my little addition to the end of it.
    – brewchez
    Nov 30, 2010 at 12:59
  • I would certainly agree that the saturation point increases, but I'm not sure that the RATE of solution varies much with temperature. Can you quantify your edit? Or provide a source?
    – Brandon
    Nov 30, 2010 at 16:28
  • Plus, how much variance in temperature can you really expect? This is for 75°F - I wouldn't expect anyone to oxygenate more than 5 or 10 degrees cooler.
    – Brandon
    Nov 30, 2010 at 16:33
  • For completeness, Palmer says that ideal oxygenation is 8-16ppm (How To Brew, 2006, page 70). Nov 30, 2010 at 17:26
  • 4
    However, this new study - done by a science-y homebrewer with access to professional testing equipment - suggests that vigorously rocking your carboy for five minutes is a very effective way of achieving maximum oxygen saturation in wort. More effective than pumped air with or without a diffuser stone. They did not test pure O2. Granted, I haven't made a beer over 1.070, but I have never had a problem with rocking not introducing enough O2 (if fermentation start and attenuation are accurate guides). Dec 18, 2013 at 17:49

To quote from http://www.wyeastlab.com/hb_oxygenation.cfm:

It was concluded that pumping compressed air through a stone is not an efficient way to provide adequate levels of DO. Traditional splashing and shaking, although laborious, is fairly efficient at dissolving up to 8 ppm oxygen. To increase levels of oxygen, the carboy headspace can be purged with pure oxygen prior to shaking. The easiest and most effective method remains injecting pure oxygen through a scintered stone."

| Method                    | DO ppm   | Time          |
| Siphon Spray              | 4 ppm    | 0 sec.        |
| Splashing & Shaking       | 8 ppm    | 40 sec.       |
| Aquarium Pump w/ stone    | 8 ppm    | 5 min         |
| Pure Oxygen w/ stone      | 0-26ppm  | 60 sec (12ppm)|

I pour my wort into a bottling bucket and then letting it freefall from the spigot into the fermenting bucket about 2 feet below it. It's easy and it works well for me. I put aeration on the "art" side of brewing as opposed to the "science" side b/c I have no idea how to calculate O2 parts per million in my beer...

Also, I watched my buddy "shake" his wort to aerate it and dropped the bucket, the lid broke, and his garage was covered with 5 gallons of "floor beer."

  • I would like to disagree with you but I can't LOL I too have no way of knowing how much O2 parts i have in my beer. I have airated with a paint mixer on a drill recently, but see no difference in the beer... and, I also do the heavy pour method Cheers!
    – Ugly Dude
    Apr 3, 2014 at 19:38
  • I just had to resort to this method when my wort pump's power pack blew as I started. I just freefall siphoned it from kettle to fermentor a couple of times. By the end there was more foam than pump achieved, so I'm thinking I should hopefully have approaching 8 ppm.
    – geotheory
    Mar 12, 2015 at 20:01

We use a spaghetti strainer to aerate by lifting and splashing just as our wort chiller brings the temperature below 80. Hot liquids don't hold as much oxygen, so we wait until the end of the chill. Jim F

  • Nice idea with the strainer. I should've thought of that
    – geotheory
    Mar 12, 2015 at 20:02
  • Also, it's good to note that aeration while the wort is too hot causes oxidation, the best temp to aerate is below 80°F/27°C. "Aeration of hot wort will cause the oxygen to bind chemically to various wort compounds. Over time, these compounds will break down, freeing atomic oxygen back into the beer, where it can oxidize the fatty acids and alcohols, producing off-flavors and aromas like wet cardboard or sherry." - Palmer, John J. How to Brew p. 71-72
    – nevets138
    Jun 23, 2016 at 1:35
  • @nevets138 I realize that Palmer is a Beer God, but this sounds pretty hand-wavy. If oxygen forms a covalent bond to "these compounds" at higher temperatures, there doesn't seem to be a good thermodynamic rationale for why these would be slowly released as "atomic oxygen back into the beer". I have no problem with the assertion that is is not a good idea to oxygenate at high temperatures but my analysis would be that this is because it just won't work. The O2 will just stay in the bubbles that reach the surface rather than dissolving as it would in colder liquid.
    – 42-
    Aug 10, 2020 at 23:58

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