Aeration of the fermenter

[RotorHead6]

I am starting this thread looking for some feedback of different types of aeration and how it has helped others brews. I also have a question that if you do not aerate if it actually takes longer for the fermentation process to start. Please list your thoughts. Also, are there ways to make your own aerator at home?

 

[Thalon]

Boiling water (wort) for 60 minutes is what releases all the dissolved oxygen that the water had naturally. So if you do only partial boils and top off with water that hasn't been boiled (or only momentarily been brought to a boil to sanitize it), you shouldn't need additional aeration at all. It's only when you're doing full boils that aeration is required.

Yes it makes a HUGE difference. I went to full boils long before I learned about aeration, and I couldn't figure out why my beers were taking so long to start fermenting, having trouble finishing fermentation and just would not carbonate in the bottle. It's because I wasn't providing enough oxygen for the yeast to reproduce into the quantity required to ferment 5 gallons. Once I started aerating is when my beers got better than my partial-boil batches.

Some people vigorously shake the carboy full of cooled wort for a strong 5 minutes (free but quite difficult and somewhat unsafe when using glass carboys). Others buy an Oxygen Injection System, which works great but it's possible to over-aerate the wort if you leave it too long. My preferred method is a simple aquarium air pump and air stone setup (thoroughly sanitized of course), along with an air filter (before Midwest ran out of them...). I just let it sit in StarSan while the wort is chilling after the boil, half the time off and half the time bubbling, then once the wort is pitching temp I let it run in the kettle covered for 15-20 min. Works great for me.

Hope that helps!

 

[abracadabra]

thers buy an Oxygen Injection System, which works great but it's possible to over-aerate the wort if you leave it too long. !

A slight correction:
It is not possible to over aerate as aeration occurs using air as with an aquarium pump. It is possible to over oxygenate or oxidize your wort using Oxygen Injection but the problem is often over stated. 10 - 15 seconds of oxygen is usually sufficent for 5 gal. It may seem like a matter of semantics but there is a difference between aeration and oxygenation.

Long term the oxygen method is more expensive as you have to continue to purchase O2 where aeration method using an aquarium pump is a 1 time purchase.

Other ways to aerate your wort would be to let the wort free fall from the boil kettle into the fermenter simply letting it splash into the bottom or have the wort free fall into a wire mesh strainer as it flows from the boil kettle to the fermenter.

 

[TheJadedDog]

I pour my wort through a strainer and try to splash it around as much as possible, then I go with the shake method mentioned above (but only because the aeration stone is lower on my list of needed equipment). So far it has worked well for me.

 

[ohiobrewtus]

I don't aerate with an aquarium pump or any other type of aeration system and I've never had a problem with slow fermentations. Once my wort is cooled I beat the hell out of it for a few minutes with a sanitized stainless steel whisk right before I pitch.

I normally start to see activity in under 12 hours. I also make some mega starters. Aeration and the number of active yeast cells will directly influence how long it takes for agressive fermentation to begin.

 

[krispy d]

aquarium pump here. in addition to a big starter I get quick and aggressive fermentations.

 

[heertsy]

I use a whip stir aerator, cost about 10 bucks but it is essentially a long attachment that goes on your drill.

 

[RotorHead6]

So is has anyone actually heard of aerating with medical grade oxygen? It sound like 10-15 seconds worth of pure oxygen introduction with a tube that reaches to the bottom of the fermenter would be enough to do the trick. Please tell me if I'm wrong here.

 

[Evan!]

So is has anyone actually heard of aerating with medical grade oxygen? It sound like 10-15 seconds worth of pure oxygen introduction with a tube that reaches to the bottom of the fermenter would be enough to do the trick. Please tell me if I'm wrong here.

Yes...you can do this with oxygen tanks from the hardware store, as they're sanitary.

Just get one of these ******* and hook it up.

 

[Coastie]

I use an aquarium pump and have liked the results.

 

[RotorHead6]

How long should you introduce pure oxygen into the wort before stopping? I don't was to over oxygenate or oxydize the beer.

 

[DeathBrewer]

2-3 minutes is what i've heard.

 

[Vermicous]

Every thing I have read has said it is really hard for a homebrewer to over oxygenate. This seems to be more of a problem for commercial brewers when they completely saturate the wort.

If anyone has had a problem, please correct me. I have oxygenated for about 5 mins (pure O2) with my lagers. After seven months they are only now showing signs of oxidation.

 

[rockout]

This all sounds a little nutty, pumps and all that.... I just pour my wort from a foot above the fermenter so that I get a lot of splashing, I stir vigorously to splash some more with a massive (sanitized) stainless steel spoon, and I've never had a problem.

I think this topic may qualify for a good ol' RDWHAHB

 

[Fingers]

Now I'm confused. I'll oxygenating my wort this weekend with my O2 tank from the oxy setup. I had heard 2 -3 minutes too, but now I'm wondering.

 

[RotorHead6]

2-3 minutes sound reasonable but I'm still learning about this stuff.

 

[Bobby_M]

2 minutes is plenty.

 

[ajf]

To see a brief comparison of the various methods and see how long you need to use pure oxygen see http://www.tcbrewmasters.org/articles/5.PDF

Also, oxygenation is simply dissolving oxygen in the wort. Oxidation requires a chemical bonding of the oxygen to produce oxides. Excessive oxygenation does not result in oxidation unless it is done at high temperatures.

-a.

 

[Crazytwoknobs]

Is anyone worried about oils and nonsense from cheap aquarium pumps? I'd be cautious about that, but I'm paranoid about that kind of thing (chem lab technique has come to dominate my brewing...).

I partial boil and pour into unboiled water (I don't try too hard to splash). Would I see poor results if I used a pump?

Would a simple piece of cotton in the aquarium tube be enough to filter out unexpected nonsense from the pump, or would the stone take care of it?

 

[Orfy]

20 second bursts over several minutes will do it.

What type of beers doing?

What yeast are you using?

Are you using starter?

How do you get the beer from kettle to keg?

 

[Mr Nick]

Is anyone worried about oils and nonsense from cheap aquarium pumps? I'd be cautious about that, but I'm paranoid about that kind of thing (chem lab technique has come to dominate my brewing...).

I partial boil and pour into unboiled water (I don't try too hard to splash). Would I see poor results if I used a pump?

Would a simple piece of cotton in the aquarium tube be enough to filter out unexpected nonsense from the pump, or would the stone take care of it?

I used to breed aquarium fish. And have experience with these air pumps.

As for oils??? What oils? Oils would kill the fish!

As for unexpected nonsense??? What unexpected nonsense? The same unexpected nonsense that one would encounter in the air that would oxygenate your wort any way?

Inside issues may be filtering the way that you are seeing this issue, but are likely not a problem as I don't think your beer would suffer because of them.

 

[Crazytwoknobs]

Yeah, I did the aquarium thing when I was younger. One day I noticed oils floating on the surface of the water, like in a parking lot after it rains, but smaller. Eventually I narrowed it down to the pump (I thought it was the tubing and the filter at first). And yeah, there would be stuff in the air anyways... I guess I haven't trusted the pumps since, and I'm quick to blame them.

I'm gonna try this on a starter... a pump, not an O2 tank.

 

[Buford]

I use an airstone with an oxygen tank, and typically run O2 into the wort for a minute.

 

[EvilTOJ]

I use one of these to aerate. It's a tile mud mixer.

 

[FlyGuy]

I have tried most methods (including both small O2 systems and a medical O2 system), and I greatly prefer O2 injection simply for its speed, ease, and convenience. Most methods work sufficiently, if you do them properly, though. Aeration with an aeration stone is probably the most fool-proof (unless you foam over).

As for 02 injection, a 45 sec blast is about middle-of-the-road for most beers. 10 seconds is definitely too little. If you are brewing a high gravity beer, though, you may wish to oxygenate for a couple of minutes because (1) it is harder to dissolve oxygen in a more concentrated wort, and (2) oxygen is REALLY necessary with bigger beers. In fact, a second injection at 12 - 16 hours is recommended for really big beers (say 1.090 and above).

Something else that hasn't been mentioned is that you should shake/agitate your carboy while oxygenating. Otherwise, a lot of the O2 will quickly bubble up and out of your wort, wasting your efforts. If you can swirl a bit while injecting, more will stay in solution, and it will be more evenly mixed helping it stay in solution.

Cheers!

 

[Bobby_M]

I run the O2 slow enough that bubbles barely break the surface so that not much is wasted. I suppose one foolproof method would be to fill the headspace with o2, cap the carboy, shake shake shake. Then again, I got O2 to not have to shake.

 

[FlyGuy]

I run the O2 slow enough that bubbles barely break the surface so that not much is wasted. I suppose one foolproof method would be to fill the headspace with o2, cap the carboy, shake shake shake. Then again, I got O2 to not have to shake.

Regulating the flow should work too. But be sure to bump up the amount of time injecting O2 because it is going to take longer to get the same amount in.

 

[FSR402]

I was thinking of trying something new (for me) on this weekends brew.
I was going to put the stone into the carboy and turn on the pump just before I start draining the hot wort thru my CFC and into the carboy. This should give me about a half an hour on the pump while the wort is transfering.
Then maybe give it 5 or 10 more minutes before pitching the yeast.

 

[Shoopdog]

Is it necessary to buy the O2 system with the inline filter, or will the system be ok without the filter? I bought one without the filter, but haven't had a chance to use it yet.

 

[FSR402]

Is it necessary to buy the O2 system with the inline filter, or will the system be ok without the filter? I bought one without the filter, but haven't had a chance to use it yet.

An O2 tank yes, a pump no.