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Surprising Aeration Results

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I think shaking a sealed carboy (or Better Bottle in my case) is a pretty low risk of contamination. Maybe a bucket would have a higher risk. I can't back this scientifically, but I can say that in the 30 or so BBs I've shaken, I've never had an infection. Also, even dry yeast lists bacterial contaminates. Heck, the post-boil wort is exposed to the air for a time as well. So, knock on wood, I'm gonna shake my booty... I mean Better Bottle.;)... until I want to experiment with getting slightly better attenuation.
 
Time for someone to build a DIY carboy shaker.

How about modifying one of these?

miracle%20mixer.jpg
 
My question for all this would be, how long does the dissolved O2 stay in the wort? If it doesn't last any more than an hour or two, have you really done anything? I've tried aereated and non and saw no noticeable difference in my fermentations, so I don't even waste my time aereating. My beers taste damn good to me when I'm done.
 
My question for all this would be, how long does the dissolved O2 stay in the wort? If it doesn't last any more than an hour or two, have you really done anything?

I don't know the exact number of hours ( I want to say around 8 hrs, but I'm not sure). But I do know that, with the right yeast cell count, it's long enough for the yeast to use the oxygen they need.
 
I stirred the heck out of my wort while I had the chiller in place and am cooling the wort down ...10 minutes or so of vigorous stirring on my last batch of brew created some awesome amount of krasuing and no doubt some very happy yeasties.

I typically stir the wort while I am chilling it since it helps it get the temperature down faster ...this time on a whim I just stirred harder sloshing the wort around in the kettle a little bit.

Seemed to do the trick pretty well
 
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.

And how does adding bottled spring water ad O2? Unless you've actually airated it, I don't think it'd have much O2 in it... your tap water with that airater on your faucet probably has more O2 in it.

Peraonlly, I use an oxygen tank and air stone, but many people have made great beers without it, so that in itself is a debated point. I'd like to see an experiment that someone split a batch of beer into a few containers, one with no airation, one with some, and one that was airated to saturation, then ferment them all and see if you can taste any differnece in the final product. But even then that might be a pointless experiment as they all might tast just great, but just slightly different, and it might depend on what strain of yest you use.
 
I never had a problem with areation, but just 'scuz I upgraded to O2 and an airstone.

Works fantastic. I give it a few minutes in starsan, blow some O2 through it (which pure O2 has slight antibacterial properties I believe), and I'm good to go.

I figure, why worry?
 
I'm an extract brewer...As my immersion chiller is cooling my wort:

1) I add two gal of filtered water (Phoenix water is very hard and nasty) to my glass primary and shake the hell out it. 2) After the wort is cooled, transfer it through a funnel and screen and let it slosh/mix with the aerated water in my primary. 3) top up with more filtered water if needed 4) shake some more to make sure that the wort is mixed with the water.

This method works great, and never had slow yeast activity. The best part is that the glass carboy is much lighter when shaking/agitating two gallons vs 5.5 gallons.
 
I'm an extract brewer...As my immersion chiller is cooling my wort:

1) I add two gal of filtered water (Phoenix water is very hard and nasty) to my glass primary and shake the hell out it. 2) After the wort is cooled, transfer it through a funnel and screen and let it slosh/mix with the aerated water in my primary. 3) top up with more filtered water if needed 4) shake some more to make sure that the wort is mixed with the water.

This method works great, and never had slow yeast activity. The best part is that the glass carboy is much lighter when shaking/agitating two gallons vs 5.5 gallons.

I have used a variation of this before... I added 2 gallons of ice cold spring water from the store directly into the kettle when I completed the boil. This immediately dropped the temp of the wort very quickly. Then let my immersion chiller finish it off. Great cold break. I assume that the spring water contained a lot of air because I didn't shake or anything and the fermentation was fine.

I thought maybe switching up and adding the water after letting the chiller do it's business... that last 15-20 degrees is always the slowest.
 
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.
 
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.
 
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.
 
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.
 
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.
 
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.
 
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.
 
I'd like to see the results from using a paint stirrer....
 
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. ;)
 
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
 
I'm also in the same book right now.

:off:
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 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.
 
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 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.
 
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.
 
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