Oxygen - Home Brew Forums
Register Now For Free!

Home Brew Forums > Home Brewing Beer > Beginners Beer Brewing Forum > Oxygen

Thread Tools
Old 07-01-2009, 07:10 PM   #1
Mar 2009
Dallas, TX
Posts: 1,112
Liked 35 Times on 28 Posts

I have a question on oxygenzation. If you pitch your yeast and then shake the carboy, would this create oxygenzation? How about if it starts to ferment and you shake the primary would this create it? Or is oxygenzation more of a concern after fermentation has stopped because the yeast won't eat up the remaining oxygen in the solution....Hopefully this makes sense. Thanks.
Scrat Brewing Company

Reply With Quote
Old 07-01-2009, 07:16 PM   #2
Feb 2009
Posts: 131
Liked 2 Times on 2 Posts

Yeast can live aerobically (with oxygen) or anaerobically (without oxygen). When fermentation is just starting, the yeast use the oxygen in the wort and the fermenter to reproduce. After they oxygen is depleted, they (mostly) stop reproducing and just go about eating the sugars and turning them into carbon dioxide and alcohol. You are right that aeration/oxygenation is a problem after the fermentation is complete, because then the yeast are inactive and cannot consume the oxygen, leading to spoiling of the beer.

Reply With Quote
Old 07-01-2009, 07:18 PM   #3
Zen_Brew's Avatar
May 2009
Posts: 1,864
Liked 23 Times on 23 Posts

Yes, aggressively shaking the fermetor after pitching yeast is a common method for oxygenating the wort. You can do this a couple times an hour for the first hour or two if you like. You can also use an aquarium pump with a sanitary in line filter to introduce oxygen. Lastly you can inject oxygen from an oxygen tank.

The first two methods will get you around 8ppm oxygen in the solution. Injecting oxygen from an oxygen tank with a 2 micron stainless stone for about 60 seconds will get you around 10ppm oxygen. This is probably closer to what a commercial brewery gets to, and is a bit better than just shaking.

You should refrain from shaking after fermentation has begun as you do not want to introduce oxygen once there is alcohol in the wort. Oxygenated beer is not a good thing. Oxygenated wort is OK as the yeast will use up the oxygen while they are reproducing.
Primary: German Hef, Belgian IPA, Scottish 80, Belgian Dubbel
On Tap: Oatmeal Stout, Vanilla Oatmeal Stout, Belgian Dark Strong, Munich Dunkel, Dunkel Weizen, Oktoberfest, Bock, IPA, Black IPA, English IPA, Pale Ale

Using the mind to look for reality is delusion. Using your senses to look for reality is awareness.

"One time I was so desperate for a beer I snuck into the football stadium and ate the dirt under the bleachers." Homer Simpson

Life, Liberty, and the Pursuit of Hoppiness

Reply With Quote
Old 07-01-2009, 07:19 PM   #4
Mar 2009
Posts: 395
Liked 8 Times on 7 Posts

Since this seems like a follow up question I thought I'd post it here rather than creating a new thread. Does that mean then that for cases of stuck fermentation, adding additional oxygen to the partially fermented beer wouldn't be a problem as the yeast would still use it to reproduce?

Reply With Quote
Old 07-01-2009, 07:50 PM   #5
beerkrump's Avatar
Mar 2009
Triune, TN
Posts: 2,113
Liked 14 Times on 14 Posts

Put simply, oxidation is an issue during storage and aging, not fermentation. Yeast metabolize O2. Also, oxygenation is the introduction of oxygen to a solution. Oxidation is what causes spoilage and rust and is a chemical reaction that can be facilitated by oxygen. Frequently, the two terms are interchanged. Don't worry, the yeast know what they are doing.

Reply With Quote
Thread Tools

Similar Threads
Thread Thread Starter Forum Replies Last Post
Oxygen for airation/can I use industrial oxygen? Mainebrew Equipment/Sanitation 20 10-19-2012 07:45 PM
How much oxygen (and how much O2 is too much)? caskconditioned General Techniques 3 11-24-2008 11:36 PM
Where do you get Oxygen? Hoosier General Beer Discussion 10 11-17-2008 11:46 PM
Just how bad is oxygen anyway? kontreren Beginners Beer Brewing Forum 19 10-28-2008 06:04 PM
Too Much Oxygen??? JimiGibbs Beginners Beer Brewing Forum 6 01-15-2006 02:50 AM

Forum Jump