Do you shake it?

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Kugster

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Just out of curiosity...

How many of you shake your fermenter during fermentation? I know I shake my starters, why not the batch? If you do, do you notice any diff. in attenuation? Can it make that more of a difference? Can you harm the yeast...I wouldn't think so but may be wrong.

Brewed a 1.063 last night using yeast 1332...wanna see how it is...been using safeale 05 for a while and had to change up, plus my LHBS doesn't carry WL's...anyways, fermentation is going real good at 24hrs...

this is when the question of shaking came to mind...just your thoughts...

Cheers :rockin:
 
Shaking introduces oxygen to the wort, which IIRC is used most during the yeast's reproduction phase. Therefore shaking after the main fermentation has begun (after reproduction) will just lead to an oxidized flavor in the beer.

If fermentation stalls, swirling the beer is a last resort to get the yeast in suspension and fermenting sugars again. However, that is only of mash temps, yeast pitching rates, and other factors point to a lower expected SG.
 
If fermentation has been going for a while the head space should be full of co2 not oxegen so i tend to think it shouldnt matter,that being said i try not to shake mine.Sometimes i have to move mine to differant spots in my house to keep temps right and they get shaken up quit a bit going up or down stairs and theyve tasted ok to me??
 
Dont shake it! The only reason you do for a starter is to introduce more Oxygen. Actively fermenting yeast churns the beer for you, let them do the work without the risk of oxidizing your beer.

Pitch the yeast, come back 2-3 weeks later.
 
I confess, I am a primary swirler...

I do a lot of Ales with WLP002, and it flocculates so fast and well that I tend to swirl it back into suspension within the first three days (gently enough to slightly drive off a bit of CO2, but not so significantly disturb my CO2 layer or spill a full airlock)... The placebo effect in my mind is that I get a point or two better attenuation with this yeast than with a simple "pitch and forget" technique.

OCD and unnecessary, I admit. I will proudly say, though, that I am not tempted to do this with hefeweizens or other yeast strains.

-Just airing my dirty laundry on this thread, I guess-

...All this will change when I finally switch to a conical, where I will be less likely to see the process, and it will be more easy to pull a SG sample (to help distill my voodoo attenuation theories)... Until then, though, I will probably rouse the "lazy" WLP002.
 
If fermentation has been going for a while the head space should be full of co2 not oxegen so i tend to think it shouldnt matter,that being said i try not to shake mine.Sometimes i have to move mine to differant spots in my house to keep temps right and they get shaken up quit a bit going up or down stairs and theyve tasted ok to me??

I've been making an argument against the concept of a CO2 blanket recently. If you think about it, air has CO2 in it - and lots of other gases too. Yes, CO2 is heavier than air, but there's always going to be some mixing.

CO2 and air are not like oil and water. Oil and water are cohesive molecules that stick to themselves, and they are also extremely repellent of each other. Not the same with CO2 and the various mixes of gases in air.

So I'm sure that fermentation at least helps shift the gas mixture in the carboy's headspace towards CO2, I'd be surprised if you could truly push out all the air.
 
air is .039% CO2.

when beer ferments it produces CO2, which forces whatever else is in the headspace (air) out of the airlock. it keeps purging as it keeps producing.
 
Compare pouring dense wort into water - yes, it sinks to the bottom, but there's also some mixing.

Do you really think that your headspace is 100% CO2 at the end of fermentation?
 
If fermentation has been going for a while the head space should be full of co2 not oxegen so i tend to think it shouldnt matter,that being said i try not to shake mine.Sometimes i have to move mine to differant spots in my house to keep temps right and they get shaken up quit a bit going up or down stairs and theyve tasted ok to me??

But if you mess with your fermenter in anyway like to open it up to take a reading or something, you've violated the integrity of the co2 space, so I wouldn't trust that all you've got is co2 in there. If you got some o2 in there, you're much closer to having liquid cardboard than someone who DOESN'T vshake is. So to me shaking it is not worth the risk, and pretty idiotic. Most people who do it are trying to make their stupid airlock bubble...it's really not helping anything.

In fact if your krausen is there, you could be knocking it down, so it doesn't have the opportunity to actually fall through in the normal course of things, and act as a filter to pull stuff down with it as it goes. So you could be losing some nice conditioning tools.

Like other's have said, intitially we shake things to introduce o2 so other than that, there's no practical reason for doing it, so why bother? Give you wort plenty of oxygen before you pitch the yeast and then them do their job.

I believe in the pitch the yeast and come back in a month method of brewing. The yeast knows how to do things, they've been brewing beer since before we were a drip running down momma's leg, so get the heck out of their way and let them do their jobs.

Seriously, what benefits do you think you're getting from doing it, besides it makes the airlock bubble and it makes you feel like you're in charge of things, when in reality the yeast are and they don't need any help from you?
 
Shaking a fermentor will not introduce enough oxygen to do any good. You'd have to do it for 45 minutes straight to equal the amount of aeration other methods yield. Pitch the yeast and go on with life.
 
Shaking a fermentor will not introduce enough oxygen to do any good. You'd have to do it for 45 minutes straight to equal the amount of aeration other methods yield. Pitch the yeast and go on with life.

We're not talking pre-fermentation here, we're talking post. But I thought the latest studies put shaking at a pretty good way to do things, at least much better than you contend.
 
According to Jamil and Palmer on several occasions, if you're going to aerate, use a stone not shaking. Shaking is a waste of your time.
 
According to Jamil and Palmer on several occasions, if you're going to aerate, use a stone not shaking. Shaking is a waste of your time.

Actually it appears the folks at wyyeast beg to differ.

Method DO ppm Time
Siphon Spray 4 ppm 0 sec.
Splashing & Shaking 8 ppm 40 sec.
Aquarium Pump w/ stone 8 ppm 5 min
Pure Oxygen w/ stone 0-26ppm 60 sec (12ppm)

It was concluded that pumping compressed air through a stone is not an efficient way to provide adequate levels of DO. Traditional splashing and shaking, although laborious, is fairly efficient at dissolving up to 8 ppm oxygen. To increase levels of oxygen, the carboy headspace can be purged with pure oxygen prior to shaking. The easiest and most effective method remains injecting pure oxygen through a scintered stone.
 
I tend to think a lot more oxygen would be introduced when someone transfers to a secondary than swirling their carboy.I try to do niether unless im lagering or moving a carboy.I wonder how much oxygen touches somones beer when they bottle or keg a beer.Has anyone on here ever oxidized their beer by accident???
 
Actually it appears the folks at wyyeast beg to differ.
Which leaves the topic to debate. I personally don't shake the fermenter, don't believe it benefits it, and prefer to just let things happen. If someone else wants to shake their fermenter, have at it.
 
Generally you should never have a need. However, the one time I used Wyeast 1338 the stuff would not drop. After about 4 weeks the gravity had gone from 1.068 to 1.022 and would not budge. I decided to give it a shake to drop the yeast and it fell and a day later it was right back on top. I kept doing this for about 5 days and one day I came back and the beer was clear. Took another gravity reading and it was 1.011. So, for that strain for that brew for whatever reason, it needed some help getting knocked into the wort to do its thing. But in general, shaking should fall into last ditch efforts if something got screwed up.
 
I will admit that I do not shake my fermenter...tho have been tempted to just because of what I thought I read somewhere...I get pretty good aeration and usually just leave it alone for a few weeks. If i do have to move it I am pretty careful not to shake too much.
 
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