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View Full Version : Degassing, revisited



Tiwas
03-20-2011, 08:38 AM
Hi guys,

First of all - if this has been answered before I'm sorry. Couldn't find the answer to my exact question, and I wasn't allowed to tag along on http://www.gotmead.com/forum/showthread.php?t=8506. As you may have noticed, my favorite question is "Why?", and I love to follow it up with "Cool! Why?" ;)

The question I have today is with the degassing tools available. I see people recommend them for both aerating and degassing, but they also say you shouldn't worry about oxidation when degassing. So...Is this because of the CO2 in the headspace when degassing, or is it that you'd degas far enough under the surface to avoid breaking the surface, while aerating nearer the top?

Does it matter if it's being done in a bucket or carboy?

I love details, so please elaborate if you can.

P.S. If I ask stupid questions, please feel free to say something along the lines of "For crying out loud! Will you shut up already??" :p

fatbloke
03-20-2011, 10:38 AM
Hi guys,

First of all - if this has been answered before I'm sorry. Couldn't find the answer to my exact question, and I wasn't allowed to tag along on http://www.gotmead.com/forum/showthread.php?t=8506. As you may have noticed, my favorite question is "Why?", and I love to follow it up with "Cool! Why?" ;)

The question I have today is with the degassing tools available. I see people recommend them for both aerating and degassing, but they also say you shouldn't worry about oxidation when degassing. So...Is this because of the CO2 in the headspace when degassing, or is it that you'd degas far enough under the surface to avoid breaking the surface, while aerating nearer the top?

Does it matter if it's being done in a bucket or carboy?

I love details, so please elaborate if you can.

P.S. If I ask stupid questions, please feel free to say something along the lines of "For crying out loud! Will you shut up already??" :p
depends on how you want to carry out the de-gassing.

whiz sticks, or stirring paddles, or even plastic spoons and the like for manual stirring type de-gassing, or of course, you can use a vacuum pump. From devices like the ones designed for bleeding car brakes, just connected through a bung with tubing, on to using an enolmatic vacuum bottler, or even an industrial grade vacuum pump.

Some people will rack and degas at the same time......

regards

fatbloke

Tiwas
03-20-2011, 10:53 AM
I was thinking about something like this (http://vinogbar.no/product_info.php?cPath=190_201&products_id=214), which can probably just go down the hole for the air lock, or one of those drill attachments with some small paddles on them, like this lees stirrer (http://morewinepro.com/view_product/19688/100485?PHPSESSID=50f25fb72475b47a97).

AToE
03-20-2011, 01:56 PM
You don't have to worry about O2 when degassing in secondary because you're not going to be rough with it, it's a gentle stirring - as opposed to the splashing of aeration. Unless you spend a lot of time splashing the surface, it won't be oxidizing.

Also, the CO2 coming out of solution does help a little, but it displaces very quickly so it's not really much protection.

TheAlchemist
03-21-2011, 10:56 PM
There's always simethicone (Gas-X in the US).

Tiwas
03-22-2011, 12:15 AM
Did you guys look at the first link in my previous post? It's a pump pumping sterile air into the must and apparently that will bind to the co2 and pull it up. For wine, anything from 30 min to 2 hours is supposed to be fine as a final degas. I'm kind of sitting on the fence :S

Chevette Girl
03-22-2011, 01:06 AM
Heh, couldn't read the details on the link... so that's what it does. Sterile or not, wouldn't that run the risk of oxidation, since air is roughly 20% oxygen?

Tiwas
03-22-2011, 01:36 AM
Heh, couldn't read the details on the link... so that's what it does. Sterile or not, wouldn't that run the risk of oxidation, since air is roughly 20% oxygen?

It basically says "You don't have to shake your carboy. Will efficiently remove co2 from your wine".

I would actually think this would be great for the first third of the fementation, but until someone here tells me it's safe I'm keeping my distance ;)

Medsen Fey
03-22-2011, 12:24 PM
There's always simethicone (Gas-X in the US).
That works for preventing foam from forming but won't really speed up the release of CO2 from solution.


Did you guys look at the first link in my previous post? It's a pump pumping sterile air into the must and apparently that will bind to the co2 and pull it up. For wine, anything from 30 min to 2 hours is supposed to be fine as a final degas. I'm kind of sitting on the fence :S

Sparging, which is the process of bubbling another gas through the liquid, will allow CO2 to form in the bubble and will allow de-gassing of the mead fairly quickly. Sparging with nitrogen is done by some commercial wineries. However, you don't want to sparge with air or an oxygen-containing gas (except at the beginning of fermentation) because that runs a high risk of oxidizing the final product.

Your other options include letting it sit and de-gas naturally over time (which occurs much faster at room temperature) in the same way that a carbonated soda goes flat if you leave it open and sitting on a table. Rackings will speed the release of CO2.

Or, you can use a lees stirrer to gently swirl the must and allow the CO2 release through agitation. There is some oxygen exposure when doing this, but probably no more than you get through racking.

Or, you can use a vacuum process to pull the CO2 out. There are many devices and systems that people have put together; some are manual pumps, some are electric. They will effectively do the job.

Or, you can use filtration. After running through a filter most of the CO2 will be released through agitation due to turbulent flow. If not done in a sealed system this can allow excessive oxidation.

Tiwas
03-22-2011, 02:06 PM
Thanks :) After I rack to secondary, I will leave my carboy up here where I can monitor the air lock properly. After a few weeks I will move it down into the basement for aging, so none of those gizmos would be necessary, then...?...

The swirling of the carboy seems to get rid of a lot of the co2, too. After a proper swirling, there's almost no airlock activity for a couple of hours before it speeds up again. Since the headspace should be filled with co2 already and I don't open the lid, I guess this would be the best way to do it. At least for now. Or am I wrong? ;)

Medsen Fey
03-22-2011, 02:55 PM
The swirling of the carboy seems to get rid of a lot of the co2, too. ... Since the headspace should be filled with co2 already and I don't open the lid, I guess this would be the best way to do it. At least for now. Or am I wrong? ;)

It works for me. :)

Chevette Girl
03-23-2011, 02:10 PM
Me too ;D I figure if it's releasing CO2 and there's an airlock, you're all good...

wildoates
03-27-2011, 07:49 PM
It works for me. :)

Me too. I splash like crazy in primary to the 1/3 break. Gently stir for the rest of primary, and give the carboy a jostle a few times a day for the first few days in secondary. Or until it stops putting gas through the airlock. Or until I forget all about it.

:icon_geek: