[troy@uk]

I bottle condition all of my beers so I don't have all of the CO2 tanks and equipment common to kegging. I want to have something easy and convenient to purge my carboys when I transfer from one to another.  My LHBS showed me a can made for wine makers, but it was a small aerosol can for $9. Someone else told me about baking soda and vinegar in a bottle with a hose into the carboy. This worked well but the aroma of vinegar was so strong that I'm worried about it affecting the beer's aroma. I'm hoping for something convenient, maybe that works with a CO2 cartridge or something.

[tygo]

I use a mini-keg charger.  Something like this:  http://www.northernbrewer.com/brewing/soda-keg-co2-charger.html

[James Lorden]

Those cans are generally argon gas.  They are meant to leave a thin layer on top of your wine, not to fill the entire empty area.  The argon is heavier then breathing air so in theory it forms a sort of blanket.    The baking soda and vinegar is a neat idea.  You could put that in one carboy with a carboy cap and a tube running to a second carboy through a racking cane to the bottom. Perhaps the CO2 release would flow through to the second carboy filling from the bottom forcing air out the top.  Seems like a cool experiment, but a lot of work.

If you are bottle conditioning the yeast will generally scavenge most of the O2 you pick up during the bottle fermentation.  The real problem with oxydation in bottled beer comes from force carbed beer where their isn't a bottle fermentation to suck up the O2.

[Hokerer]

I've thought about, instead of an airlock, run a hose out of the primary fermenter.  Put a two-hole stopper on the secondary with the other end of the hose connected via one of the holes.  Put the airlock in the other hole.  That way, all the CO2 put out by the primary fermentation would fill the secondary - voila... purged!

[6thstreet]

tygo's sugestion is a sound one.  I have been using this for years and it works very well.

[tom]

I've thought about, instead of an airlock, run a hose out of the primary fermenter.  Put a two-hole stopper on the secondary with the other end of the hose connected via one of the holes.  Put the airlock in the other hole.  That way, all the CO2 put out by the primary fermentation would fill the secondary - voila... purged!

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