Preventing excess exposure to O2 during secondary with small batches

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Jul 12, 2008
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Portland, OR
I have a number of carboys filled with 2-3 gallons in primary fermentation (I split up my wort to try different yeast). I have two converted freezers (with love controllers) for fermentation and clearing. I would like to rack for secondary fermentation, but I am concerned about exposure to oxygen. I have CO2 available. What procedure should I use to prevent excess exposure to oxygen? Should I do secondary in carboys or corney kegs? Thanks, Sean.
The best and easiest way would be to forget about the secondary. Lots of brewers skip the secondary and most that I've heard from say it's improved the quality of the beer.

Just leave it in the primary for a few days or a week longer than you normally would and put it in the keg.
If you have kegging equipment, then the easiest thing to do is just purge the secondary headspace with CO2 for a couple of minutes. Get some saran wrap and cover the top of the carboy with it. Make two slits - one for the input of the CO2 tubing and one as a blow-off hole. Put the CO2 tube into the empty headspace and purge at low flow for a couple of minutes. Replace saran wrap with air lock and you're done.
PS - I wouldn't agree that skipping secondary improves the quality of the beer for all types of beers (especially bigger beers). I think with most beers, doing a secondary is good practice (though obviously not required). My beers always taste better after a secondary, but If I want to get something kegged quickly, I'll skip that step.