Take the 2-minute tour ×
Homebrewing Stack Exchange is a question and answer site for dedicated home brewers and serious enthusiasts. It's 100% free, no registration required.
  • Do you notice any benefits in flavour or yeast activity over a regular air pump?
  • By not blowing dirty air through your wort, could it keep down infections/contamination?
  • Does pumping regular air through wort increase risks of infections/contamination?

Useful Pages
Oxygen Dissolved In Wort
Shaking - 4ppm
Air + Air Stone - 8ppm
Oxygen + Air Stone - 14ppm

share|improve this question
    
Asking "who" uses something isn't an objective question with a clear answer, so I've made this a community wiki. I also think you should split the last 3 questions into their own question so the answers are focused. –  mdma Jan 13 at 20:41
    
how do I get to and view the wiki? –  Another Compiler Error Jan 14 at 13:59
    
This page is the "wiki" that mdma mentioned. Notice how instead of your user profile card below your question, you see "community wiki". –  Scott Jan 14 at 14:20
add comment

3 Answers 3

up vote 3 down vote accepted

Oxygenating your wort using a tank is leaps and bounds more efficient (as well as more expensive) than agitation or splashing. Simply agitating or splashing your wort to oxygenate it will work for most average gravity beers (you're aiming for a minimum of eight parts per million of oxygen minimum), but will otherwise require a significant amount of effort if you ever need to oxygenate above eight parts per million (PPM), up to 10PPM for high gravity beers. 10PPM of oxygen would be near impossible to accomplish via splashing, since the air we breathe only contains up to 21% oxygen in it.

Using a air pump like what you would see in aquarium tanks should also be used with a High Efficiency Particulate Air (HEPA) filter to prevent any of the ambient microbial contaminants from flowing through the pump, since it is just pulling in the air around it. Also, the stones used on aquarium pumps aren't as efficient as the 0.5 micron diffusers you could get for pure oxygen tanks (plus aquarium stones fall apart quickly and leave particulates in the yeast cake). You could likely achieve the necessary 8 - 10 PPM using the stones for aquarium pumps, but it will take between 15 - 30 minutes to accomplish, where pure oxygen with a 0.5 micron diffusion stone will take only a minute or two.

If you were to taste a beer that lacked the proper levels of oxygen prior to fermentation versus a beer that was properly oxygenated, you will most certainly be able to taste the difference. The most obvious will be that the higher final gravity between the two beers. The one that lacked oxygen will have a much higher FG than the one that was properly oxygenated, the effects multiplied the higher the OG is. That said, it's been my personal experience that over-oxygenating your wort will result in a lower than anticipated FG. I recall splitting a batch for experimentation, the OG was approximately 1.068, one I aerated through agitation by setting the carboy on its side and rolling back and forth vigorously for 5 minutes. The other batch I aerated with pure oxygen for about 5-7 minutes before my tank peetered out on me, and the latter batch finished a full 10-11 gravity points lower than the one aerated through agitation (1.011 vs 1.000).

Also, you would not need to worry about filtering bottled oxygen, no contaminants would survive a can of pure, pressurized oxygen. Also, make sure there's no open flames or sparks near the wort while oxygenating using pure oxygen, as there are few gases that are readily accessible and more flammable than pure oxygen.

share|improve this answer
    
Just a minor point about the caution - oxygen itself isn't flammable, but its presence will certainly increase the potential for other flammable/combustible gas or materials to ignite. –  tallie Jan 14 at 3:56
    
Pure oxygen certainly is flammable. I use Bernzomatic Oxygen cylinders which are specifically designed for oxygen torches. I just happen to re-purpose them for oxygenating my wort. –  Scott Jan 14 at 14:13
    
I admit this is getting into terminology nit-picking, however, Oxygen itself is an oxidiser. The fuel you use with your oxy torch (Acetylene?) is flammable. I certainly did not intend to downplay your caution, as pure oxygen is indeed dangerous in the presence of combustible materials and an ignition source. –  tallie Jan 14 at 23:46
    
After doing plenty of head scratching research, I appear to be incorrect. Thank you for pointing this out. As you said though, pure, condensed oxygen in the presence of a combustion hazard will exponentially increase even the most minor of flammable explosions. A perfect (and tragic) example would be the Apollo 1 tragedy where the cabin was intentionally over-pressurized with oxygen, and even the slightest electrical arc set the entire cabin and crew ablaze. –  Scott Jan 15 at 0:37
add comment

I used to use one, but I found it a hassle to use compared to my MixStir aerator. In addition, I found the Mixstir to work as well as any other method and it's considerably less expensive.

share|improve this answer
    
How long do you go with this in higher gravity ales? I used one up until it fell apart in one of my previous batches. I've yet to rack off the beer in the carboy and retrieve the fins. –  Scott Jan 13 at 18:52
    
Until the fermenter is filled with foam. That usually takes 2-3 minutes. –  Denny Conn Jan 13 at 20:48
add comment

I recently started using O2 and temperature control, as well as turning my attention to brewing big beers (SG 1.100+). These big beers have come out clean, attenuated well, and were generally much better than previous attempts to brew even moderate beers around SG 1.070.

share|improve this answer
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.