Surprising Aeration Results

[BarleyWater]

For all of you that "slosh your carboy", if you are doing so with cap/lid on it, what are you really accomplishing? There is only so much O2 in that small amount of air so you are probably just waisting your time.

Your thinking suggests that all of the O2 from your bottle is staying in the wort. It isn't, only a small portion is. There is only so much O2 that can be absorbed, so exposing it to more doesn't mean that more will get in, only a better chance of infection. Nowhere near the amount O2 in the headspace would or could ever be absorbed into solution, so sloshing with the cap on, is just as effective, and much safer than slushing it around in an open bucket, or any other slosh method.

 

[Rumblebelly]

We do a lot of DO testing in our lab and often need to reach a target 8 +/-ppm DO for all of our initial samples. On smaller bottles, 300 mls, we use a regular aquarium pump and it takes a few minutes for it to reach the target. Granted, I'm talking aerating purified water though.

Sometimes we shake the sample and that's a much quicker way to get the DO levels up. My gut tells me that simple rocking the fermenter back and forth, with a cap on of course and sitting on something soft, would do a much better job than a regular aquarium pump.

 

[Bobby_M]

I don't know if you've heard one of the more recent episodes where the original author of the experiment called in and explained that his DO meter was defective and giving reading of up to 2.5 ppm in a sample that should have been close to zero. He mentioned he'd repeat the experiment with a new meter and more aeration techniques. I only hope he uses real wort this time.

 

[Rumblebelly]

Yeah, I read that. I'd be surpised if wort would take in more O2 than tap water but you never know. If his DO meter is that far off though, it makes me wonder what else might be wrong.

Anyway, my personal opinion is that shaking or rocking would be much more effective. If you put your finger at the end of the tube coming out of an aquarium pump, you'll notice that there isn't a whole lot of air coming out (unless you have large pump). Shaking, if aggressive enough, would move a lot more air into the solution.

I'm curious about at what gravity would pure O2 be effective. I'm planning on doing a super alt with a starting gravity at 1066.

 

[Bobby_M]

I'd say that higher gravity wort would take on LESS oxygen via shaking or air pumping and I'd just want that proven or not. The whole idea with the aquarium pump is that it's less manual labor, less chance of dropping the carboy, and less chance of contimination. The one tradeoff is time.

 

[TeleTwanger]

shaking is a major PITA compared to leaving an air stone for 30 minutes...Shaking also opens up the possiblity for infection. When I shaked I would shake for a minute or so and then stop. After a few minutes I'd take the stopper off and the carboy would suck (unfiltered) air. I'd do this maybe 10 times. Sure it works but air stones are much easier and they work better unless you shake the crap out of it.

 

[Piotr]

Shaking also opens up the possiblity for infection.

I leave and open fermenter with wort under UV lamp for a few minutes , then pitch the yeast, close the lid and shake. Strile enough.

 

[jfrizzell]

I'd also like to see a comparison with Oxygen and a 0.5 micron stone. I've read several times that a 2 micron stone does not create bubbles that area small enough to be readily absorbed. The finer bubbles created by the 0.5 micron stone are more easily absorbed into the wort. Apparently aquarium pumps don't have enough pressure to work with the 0.5 micron stone though.

 

[jfrizzell]

I leave and open fermenter with wort under UV lamp for a few minutes , then pitch the yeast, close the lid and shake. Strile enough.

UV light --> skunking? No concerns there?

 

[beretta]

I'd like to see the results from using a paint stirrer....

 

[Ecnerwal]

Personally I think some of you folks make to much of this (Imagine, I've made beer for 15 years without an airstone, much less an oxygen bottle), but you could certainly combine the yeast-starter stir-plate project into a stand that would hold a carboy and stir the whole carboy if it made you happy. Order a stir-bar retriever along with your stir-bar so you can get it out of the carboy or bucket, or order enough stir bars that you can just leave it there until you rack.

On the whole, I'd suggest making a good starter as being of more overall use than fizzing oxygen through the wort, if you were to bother to remember why we aerate the wort in the first place.

But the land of ultimate overkill has not yet been achieved. Be the first on your block with a refrigerated counterflow wort chiller that takes the wort down to 34F / 1C (because gas dissolves best in cold water-based fluids), injects pure oxygen into the chilled wort through a 0.2 micron airstone, runs it through 50 feet of tubing in an ice-water bath for additional contact time, rewarms it to pitch temperature (oxygen fizzes out) and deposits it in your primary. Then be the first to upgrade your system to 100 feet of tubing, and a yeast injector after the rewarm but before the fermenter.

I'll be over here sloshing my carboy and making beer - you have fun tinkering with your beer machine.

 

[TexLaw]

Personally I think some of you folks make to much of this (Imagine, I've made beer for 15 years without an airstone, much less an oxygen bottle).

I'll be over here sloshing my carboy and making beer - you have fun tinkering with your beer machine.

I'm right there with you: fifteen years, shaking every batch for five minutes after pitching. I just sit on the floor (on a mat, if I'm on a hard floor), set a timer for five minutes (or just look at my watch), kinda wrap my legs around the glass carboy or Better Bottle for stability, and rock the thing around. During those fifteen years, I've had one infection, no stuck fermentations, no phenols (except where desired), or anything else weird that you might attribute to less than good aeration. I also typically have lag times of only a few hours, unless I'm dealing with something like that big, bad barleywine.

Guys, other than the warm fuzzy it gives some homebrewers, I just cannot see the value in all the O2 gear.


TL

 

[gwood]

Guys, other than the warm fuzzy it gives some homebrewers, I just cannot see the value in all the O2 gear.
TL

I'm also in the same book right now. I just shake and the little guys seem to be OK with it. That said, I do love me some new toys

 

[menschmaschine]

I'm also in the same book right now.

I know it wasn't intentional, but I think that's hilarious! (I'm in the same boat). I love mixing up idioms/cliches... like that, e.g., "Well, a penny saved is worth two in the bush."... acting all serious when you say it.

Anywhoo... back to the topic.

 

[Bobby_M]

I agree to a certain point. It's a no brainer for me because I got my O2 setup for practically nothing. THough after a long brew day, I do like the idea of just cracking the valve for 60 seconds instead of doing anything like shaking. And yes, I do get a warm fuzzy knowing it's completely sanitary. I look at it as taking away one more variable and a potential for a stuck fermentation. If I'm pitching a large starter, I don't bother. However, I do bubble the oxygen into the starter anytime I step it up.

 

[gwood]

I know it wasn't intentional, but I think that's hilarious! (I'm in the same boat). I love mixing up idioms/cliches... like that, e.g., "Well, a penny saved is worth two in the bush."... acting all serious when you say it.

Anywhoo... back to the topic.

I was going to edit but I'll leave it just for you

 

[Piotr]

UV light --> skunking? No concerns there?

So far I tried it only on a few beers, mostly dark and not very hoppy. But you are right, that might cause problems...

 

[EvilTOJ]

Yea I would suggest skipping the UV lamp unless you're making a Corona clone. And yes, earlier I did post a picture of a paint can shaker. The kind you see at the paint store to mix colors.

 

[TeleTwanger]

My question is who is suprised? This is old news. Palmer talks about this in his book years ago. He found (or the study he points to from 1996 IIRC)that shaking/air pump/pure o2 all gave similar results.

 

[TheFlatline]

My question is who is suprised? This is old news. Palmer talks about this in his book years ago. He found (or the study he points to from 1996 IIRC)that shaking/air pump/pure o2 all gave similar results.

That's kind of what I figured. To me, dropping the O2 stone into the beer, cranking it up, and walking away is pretty easy. I used to whip the wort with one of those stirring rods that plug into the electric drill, which was pretty damn easy, but this is even easier. The last beer I made, a Tripel, had foam wanting to gush from the top of the carboy after the 90 seconds they suggested.

 

[debaniel]

hmmm...

the ultimate aeration experiment...


shaking
vs.
pure 02
vs.
paint shaker
vs.
olive oil
vs.
popping submerged balloons
vs.
stirring
vs.
splashing
vs.
blowing into it with a soda straw
vs.
running it through a pool pump

vs... anything else?

 

[Ecnerwal]

You missed cooling your wort with liquid oxygen, I think. Not to mention pressurizing it to get more oxygen in solution....

On the other hand, supporting my minimal method, some guy wrote (well, his writing was translated to...):

...a liquid, if shaken up with air for one minute will become perfectly saturated with oxygen. Substantially this is the case. In estimating the oxygen in different parts of a liquid treated thus, we have invariably obtained the same figures to within about 1/50th.

It's highly arguable that this guy knew what he was talking about. The 2% error would be consistent with the best he could manage for oxygen measurement not quite 150 years ago.

 

[FireBrewer]

On the whole, I'd suggest making a good starter as being of more overall use than fizzing oxygen through the wort, if you were to bother to remember why we aerate the wort in the first place.

THIS. Definitely the primary goal.

Although oxygen does have it's place. They didn't use a pure oxygen setup, as noted in the OP. With all due respect to Palmer and a few homebrewers from Basic Brewing, here's some info from a doctor (PhD) who teaches for the American Brewer's Guild:

In general, it is difficult for homebrewers to achieve sufficient oxygen levels. The levels of oxygen necessary for optimal fermentation vary depending on the yeast strain. Ale strains usually need between 8-12 part per million (ppm) while lager strains require slightly higher amounts (10-15 ppm). At atmospheric pressure the maximum level of dissolved oxygen in wort is approximately 8 ppm and the saturation level decreases further as the gravity of the wort increases. Thus unless special steps are taken to introduce air or oxygen into the wort, it is difficult for homebrewers to achieve adequate aeration. Recent studies have shown that oxygenation is by far more efficient than aeration. Injection of oxygen through a 2 micron diffusing stone can actually supersaturate the wort with 10-12 ppm of dissolved oxygen being reached in 5 gallons of wort by a single 60 second blast of oxygen!

 

[TeleTwanger]

hmmm...

the ultimate aeration experiment...


shaking
vs.
pure 02
vs.
paint shaker
vs.
olive oil
vs.
popping submerged balloons
vs.
stirring
vs.
splashing
vs.
blowing into it with a soda straw
vs.
running it through a pool pump

vs... anything else?

Hydrogen peroxide.

 

[Yuri_Rage]

vs... anything else?

Not doing a damn thing.

When you're looking for a super-clean fermentation, just pitch a very healthy, large dose of yeast, and you don't need to aerate at all. The yeast skip the reproduction phase and get right to work. This technique doesn't apply if you're into Belgian styles or ester-laden hefeweizens, since it relieves much of the "stress" that causes those funky flavors.

 

[bell0347]

If you pitch the proper amount or rate of yeast that has been started properly and pitch it at the right temp, does the aeration of the wort even matter? Maybe just shaking the crap out of a good starter solution before putting the yeast in provides adequate O's for them to reproduce well, thus when you pitch it they are ready to go with just the ambient amount of O's already in the wort. If I am wrong let me know, I am new to this and don't even pretend to know more than anyone else here. Just kinda thinking out loud.

 

[FireBrewer]

If you pitch the proper amount or rate of yeast that has been started properly and pitch it at the right temp, does the aeration of the wort even matter?

I asked this exact same question to Jamil. Whereas pitching the correct amount of healthy yeast is paramount, you still need some oxygen. You just need to add less. Simple aeration with the correct amount of yeast is appropriate.

 

[goose_on_fire]

I just drilled some small (1/16") holes in a spare bit of racking tube and inserted that into the end of the siphon hose, then let Mr. Venturi take over. You can see tiny streams of bubbles being pulled into the wort as it makes its splashy way into the carboy.

I don't actually know if it makes any difference at all, but for zero extra work and the cost of a small piece of plastic tube it can't hurt either (short of pulling contaminated air into the wort, which I'm just not worried about).

 

[BillyVegas]

Is it crazy to think that a large whisk put into the wort and worked for a few would incorporate sufficient air?

 

[wildwest450]

Is it crazy to think that a large whisk put into the wort and worked for a few would incorporate sufficient air?

How do you fit a whisk in a carboy?

 

[BillyVegas]

I have some ideas...
But you could use a bucket... like my noobish self does.

 

[craigd]

Not doing a damn thing.

When you're looking for a super-clean fermentation, just pitch a very healthy, large dose of yeast, and you don't need to aerate at all. The yeast skip the reproduction phase and get right to work. This technique doesn't apply if you're into Belgian styles or ester-laden hefeweizens, since it relieves much of the "stress" that causes those funky flavors.

I never have done aeration beyond a vigorous shake for about a minute. I was reading through this wondering why all my beers seem to kick into a good ferment within 6 hours without going to the lengths you guys are talking about but maybe this is it - I have thus far always pitched a good starter at high krausen. I suppose I should try a split batch and do some of these experiments but I am a bit lazy about it when my beers turn out okay. Are there some good experiments out there about flavor changes due to aeration or are they mostly about getting things going quicker?

 

[jds]

Is it crazy to think that a large whisk put into the wort and worked for a few would incorporate sufficient air?

How do you fit a whisk in a carboy?

Bucket fermenter.
Whisk in the BK after chilling.

I've done this with large (1.088) stouts, and had a strong start with Notty at 6 hours or so.

 

[BillyVegas]

Bucket fermenter.
Whisk in the BK after chilling.

I've done this with large (1.088) stouts, and had a strong start with Notty at 6 hours or so.

My thoughts exactly.
Whisking should incorporate a significant amount of air... pending on vigor and time I suppose.

BK? We're whisking in Whoppers into the wort now?
(no really, im a noob and don't know wht BK stands for... aside from thinking its some yeast term)

 

[boyurboy]

BK=Boil Kettle

 

[BillyVegas]

Nice!

Yea, my first brew(s) are this weekend- so I think instead of my stirring method to cool, Ill stir with a whisk to cool this mass down in the sink of ice.

Two Birds, One Whisk.

 

[camiller]

Yea I would suggest skipping the UV lamp unless you're making a Corona clone. And yes, earlier I did post a picture of a paint can shaker. The kind you see at the paint store to mix colors.

My local big box store has a shaker that can shake a 5 gallon paint bucket. don't know if it would open enough for a 6.5 gallon ale pail though.

 

[GilaMinumBeer]

Brew Ware inlcudes plans of a wooden carboy rocker for this.

I'll stick to direct inject O2 thanks.

 

[camiller]

If you pitch the proper amount or rate of yeast that has been started properly and pitch it at the right temp, does the aeration of the wort even matter? ...

I asked this exact same question to Jamil. Whereas pitching the correct amount of healthy yeast is paramount, you still need some oxygen. You just need to add less. Simple aeration with the correct amount of yeast is appropriate.

Yeah. although it would effect some styles more than others some of the flavor producing compounds produced by the yeast are made during the aerobic part of their life cycle. If we under pitch we get too much of those compounds and if we over pitch we don't get enough. So yes you still need some O2 because you do want the yeast to go through that part of their life cycle for a while.

 

[Foosinho]

I'm a gadget guy, and this thread has gotten me thinking...

... if you really want to super-aerate your wort, why not use a needle wheel pump? They are commonly used in the saltwater aquarium hobby to generate thousands of tiny air bubbles to extract dissolved proteins from the water column in a process called "skimming." It also introduces a ton of dissolved O2 to the water.

I'm building an electric brew kettle now... maybe I'll rig up a needle wheel pump to inject air into the wort on it's way to the fermenter. If you really want to avoid contamination, hook the input air line on the NW pump to a compressed O2 source with the regulator set to a relatively low pressure (maybe a smidge above atmo). :rockin:

Easy peasy, lemon squeezy.