6.5 Gallon Carboy for 5 Gallon Batch?

[ColbyBrewer]

Hello all, I'm new to brewing but have been focusing on meads the past two months. After two reasonably successful one gallon batches in little glass carboys, I recently moved up to a five gallon batch.

I used a plastic fermenting bucket for my primary, and this past Tuesday racked it into a 6.5 gallon glass carboy for the secondary. I recently realized that one of the reasons a carboy is recommended for the secondary is the lack of headspace. Naturally my five gallons don't fill it, so there's quite a bit of exposed surface.

Have I made a mistake in a batch that's too small for the size of the carboy?

 

[prandlesc]

As long as your beer is still giving off CO2, you'll be fine. The CO2 will create a blanket over your beer and keep it safe. Just curious, why did you move your beer to a secondary, or why not use the glass carboy as your fermenter?

 

[ColbyBrewer]

As long as your beer is still giving off CO2, you'll be fine. The CO2 will create a blanket over your beer and keep it safe. Just curious, why did you move your beer to a secondary, or why not use the glass carboy as your fermenter?

Well, it's mead. The book I consulted (The Compleat Meadmaker, recommended by a homebrewing store owner) said to do it basically. Ferment first in plastic or glass, then rack into a glass carboy for the secondary.

What happens when it stops producing CO2?

 

[Brewing_Ham]

As long as there is no air movement in the carboy, theoretically nothing. CO2 is more dense than O2 so it will blanket the top of your Mead preventing O2 contact. As long as your yeast is fermenting it is producing CO2, even in small amounts it would create this blanket. If your worried about changing the flavor by "topping up", you could always buy bottled CO2 and fill the extra head space with it after every time you have removed the airlock. Hope this helps

 

[loveofrose]

I've been doing this for years with no problems. You would have to do something really stupid to oxidize traditional mead. Once you add fruit, it is more prone to oxidation, but still far more resistant than beer.

 

[ColbyBrewer]

Ah! Well that's all very reassuring then, thanks.

Let's say in the future I did a five gallon melomel in this carboy. Might it be wise then to get the bottled CO2 or is it really a negligible risk as long as I keep the airlock on?

 

[loveofrose]

No risk with the airlock on. I've found airlocks blown completely off for a week with no effect on flavor.

For melomels, you will need the head space to hold the extra fruit.
Remember, it's 5 gallons of mead + the fruit!

 

[ColbyBrewer]

Excellent then! Very good to hear. Thanks.

 

[fatbloke]

Excellent then! Very good to hear. Thanks.

As per the suggestions because if you haven't made a batch thats already exceeded the yeast tolerance once you add fruit to secondary, there will often be a little further fermentation of the fruit sugars as long as you haven't stabilised first......

Just remember, many people here have made beers first and what with that needing more careful handling and management, they like to be "belt and braces" with their brews as they have trouble with the truth that something made with similar pprocesses can be so different. So they like blanketing with CO2 or sanitised glass (marbles etc) or any number of other methods to raise the liquid and remove airspace.

If you had to go for long term storage with a big airspace, either gass blanket or say WTF and bottle it........