alcibiades

Recipes 

Why not give the carboy or bucket a few shakes every now and again during the first couple days of fermentation? Wouldnt this have a "stir-starter" effect, making for better yeast production? Would oxidation be an issue? Talk amongst yourselves.

wyzazz

Recipes 

I do this everytime I walk by my fermenters, don't know if it helps out or not but it makes me feel like the yeasties "need" me to help.

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JiveTurkey

Recipes 

Yes and yes. The negative effects of oxidation would outweigh any benefit to greater yeast production. This is why pitching the proper amount of yeast to a well-aerated wort is the much better idea.

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Aging for 1 Year: #1 LHBS Standard (Dry) Stout
In bottles: #2 Honing Wit (Belgian Wit Bier w/honey); #3 Be Hoppy, Not Bitter ("Oregon" Pale Ale: APA using Oregon-inspired ingredients and lots of late-addition/dry-hops); #4 American Red-Head (Irish Red made from American ingredients); #5 Student Power Orange Ale (Orange-hued amber ale for a wedding)
Primary: [n/a]
On deck: [Thinking about it]

IrregularPulse

Recipes 

How long is the "Oxygen Good" period then where it would be good to shake?

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alcibiades

Recipes 

here is the thing about oxidation, if you keep the airlock on during the brief, yet assertive, shake...where is the oxygen going to come from?

But assuming that some oxygen gets in the fermenter during the shanke, and to answer IrregularPulse, from my limited research, the "oxygen good" period is only during the first 6-24 hours

(see http://www.maltosefalcons.com/tech/yeast-propagation-and-maintenance-principles-and-practices. Quote: "In terms of fermentation, aeration is also important but only in the early stages (first 6-24 hours). Aeration in later stages can oxidize beer constituents and lead to the development of off-flavors.")

frazier

Recipes 

I just took a look at my current batch, roughly 36 hours post-pitch. It seems to be doing a pretty good job of shaking itself!

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"Anything worth doing, is worth doing slowly." ~~ Mae West

permo

Recipes 

I also shake mine when I walk by them for the first 4-8 hours after pitching or until I see krausen starting to form. Often time, a shake is what really wakes them up and get's things going good...happened to me yesterday actually.

If you have your airlock on and functioning, I see no detrimental effects to a gentle shake or swirl. To be honest, I think our oxidation fears are vastly overrated when we are talkling about beer in the fermenter. I have re aerrated beers numerous times to encourage attenuation of big beers...never been a problem.

IrregularPulse

Recipes 

I could see shaking as a positive thing until you see signs of fermentation. Once it's going though, you wouldn't want to introduce any more.

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samc

Recipes 

I leave mine alone in it's fermentation chamber and don't touch it for 10 days. Works fine, they don't need the human touch.

DKershner

Recipes 

Yeast reproduction is not the primary concern in fermentation, so the shaking to introduce oxygen is not needed, and could cause problems.

A swirl at the end of fermentation to coax a few more points out of our friends is another story and can definitely be employed situationally to varying effects. No real danger of oxygen there.

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