View Full Version : filling the Headspace

02-26-2017, 08:47 AM
Hello Mazers (I prefer mead-eaders),

I am about to do the 1st rack from two 3gal carbouys and wondered on the recipient vessels ... should I go back to a 3gal carboy or use 1gal jugs?

the real concern is in the headspace, where a 3gal carboy won't get filled up, there will be a huge headspace. the 1gal option will get me minimal headspace, but I'll have some leftovers (to sample?) that do not fill a 1gal and will again have a huge headspace.

one option I found was a spray-can of nitrogen to fill the headspace. I could use that to fill the headspace ... potentially making the return to a 3gal recipient almost an option.

in filling the head space with this nitrogen on a mostly full carbouy and capping it with an airlock, will that solve the oxygen-touching-my-mead issue? so that I can use the partially full 3gal carbouy for a long, several month racking?


02-26-2017, 10:14 AM
Mead is not beer.

Unless you made a melomel, mead is very, very resistant to oxidation. The fruit in melomels or the grains in braggots can oxidize, but even then only with really significant long-term exposure to oxygen.

For all other styles you doing need to worry about oxidation. Especially traditionals; it's almost impossible to oxidize a traditional. You should be fine racking back to your 3gal carboy.

03-06-2017, 07:09 PM
I can't speak to the oxidation risk itself. zpeckler Says no worries, and I believe <insert whichever of the 57 genders zpeckler prefers> on that issue.

That said, I'm still paranoid. So I blanket with CO2. CO2 is much cheaper than nitrogen. Most home brew stores sell keg chargers, little hand held devices that use a 16 gram co2 canister. A little goes a long way. It comes out cold, is slightly heavier than air, so will tend to settle to the bottom of the head space and displace the air out the air lock as it expands due to rising temperature. A single canister will let you blanket half a dozen batches easily, so it's a cheap and easy way to salve your completely unscientific paranoia.

Also, if you're done with fermentation and have stabilized, I recommend silicone carboy hoods. They're better than airlocks because they can't go dry. However, if you combine both CO2 blanket and the hood, you'll want to "burp" it ever so slightly about an hour after putting it together to release just a little pressure.