Ok, for those of you concerned about swirling and oxydation (
like for a stuck fermentation), when we suggest you "swirl to rouse the yeast," we are not telling you to
shake the hell out of your fermenter like you did before you pitched the yeast.
The motion we are reffering to is less motion than even racking you beer produces.
Here's what you do...it works either with a carboy or a bucket, but I will describe it in "carboy" terms.
1 Grab the neck of the carboy with right hand.
2 Tilt the carboy until it is supported on one point on the bottom (a pivot point)
3 With the hand holding the carboy make a little rotate motion clockwise from "12 oclock" to "6 oclock" (a half twist)
4 Put fermenter back down.
That's it....no major shaking, no major foaming...just a
gentle swirl to bring the yeast off the surface.....
Some things to remember, your beer is wrapped in co2,
not oxygen and any air you left in the fermenter if you opened it for a grav reading, is rapidly pushed out your
airlock by the constant creation of co2.....That is what your arilock is for! It is not a fermentation gauge it is a valve to let out any air and excess co2....
so there is very little air in it to oxydize your beer anyway.
If you have a bucket you can even "burp" the air out like a giant tupperware container (remember the burp commercial) just remove the airlock and push down on the center of the lid, and replace the airlock, more than likely you have gotten 99% of the air in there, the co2 will void out the rest.
If you are in a better bottle, you can squeeze the bottle a bit and make the airlock bubble a bit to void out the air. If you are in glass, or don't want to burp,
you can just let your fermenter sit for an hour or so after openning it, and co2 will be produced and void out the air anyway.
In reality it takes a lot more oxygen exposure of our beer to cause any damage...in a basic brewing podcast years ago, one of the big wigs, John Palmer, or Chris Colby (the editor of BYO) said that the amount of oxygen to actually damage our beer, is actually
far in excess of what we do in the normal course of brewing and even most of our accidents. And requires about the amount of oxygen that we could pump in by emptying one of our red oxygen bottles with an airstone into our bottling bucket....
not the normal amount of motion we make if we are careful brewers.
Also the effects of oxydation are
long term they affect the storage of beers...Unless you pumped an oxygen bottle into your finished beer,
you will have consumed your two cases of beer long before any signs of oxydation would show up.
Finally, if you brew from fear, you won't make good beer.
Give your beer some credit...it has managed to survive over 4,000 years of brewing, long before germ theory, long before the internets, brewed in some brutal conditions, and managed to survive.
I can't say this enough, your beer is much hardier than most new brewers give it credit.
Read the stories in hear, and you will see that our beer manages to turn out great, in spite of what we do to it!
https://www.homebrewtalk.com/f39/wh...where-your-beer-still-turned-out-great-96780/
That's why over and over, we say to relax...as long as you are relatively careful, your beer will turn out fine. 99.5% of the time, it does.
I just came upon something interesting in regards to "stuck fermentation" adding yeast hulls, which are basically dead unviable yeast. You can buy it from most lhbs's, but can also buy it at health food stores (that is what brewer's yeast" in the health food store is...non viable yeast. Ot all those old yeast packets that may have been left over from the mr beer days, that are outdated and dead...Or that jar of bread yeast that was supposed to be kept in the freezer, but your ex girflriend who broke up with you and was packing all the stuff you left over there, and didn't heed the instructions and left in her hot garage til you came over (along with that jar of beautifully rendered duck fat, the B*#ch)..But I digresss 
