Degassing…

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Can you Degas a second time? I racked my wine (a Sauvignon Blanc ) and degassed it, added Potassium Metabisulfite, and then a clearifier. Even added a bottle to top off. Days later I see my air locks with pressure. Not bubbling. I fear I might have not degassed enough. Before I bottle, can I degas again or will it add to much oxygen?
 

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Yes you can degas more.
Many wines have some residual CO2 , so I have to ask why bother? Is it creating bubbles on the sides of a glass or gravity cylinder? do you get bitter flavor notes?

A practical definition of fully degassed is it can hold minus five inches vacuum and hold it for thirty minutes. (the bulb on a head space eliminator pulls in at minus five)
If I was needing to degas, I would pull a slight vacuum over night, ,,, example a vacuum cleaner pulls minus five inches of mercury, or the inexpensive 12 volt pump on my bench pulls minus 22 inches mercury.
 
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Yes you can degas more.
Many wines have some residual CO2 , so I have to ask why bother? Is it creating bubbles on the sides of a glass or gravity cylinder? do you get bitter flavor notes?

A practical definition of fully degassed is it can hold minus five inches vacuum and hold it for thirty minutes. (the bulb on a head space eliminator pulls in at minus five)
If I was needing to degas, I would pull a slight vacuum over night, ,,, example a vacuum cleaner pulls minus five inches of mercury, or the inexpensive 12 volt pump on my bench pulls minus 22 inches mercury.
Thank you for the advice!
 
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I agree with @Rice_Guy. Even with degassing, wine can continue to expel CO2 for days or weeks. Plus changes in air pressure and temperature will affect the airlock.

When degassing I probably do 20 to 30 seconds, changing direction 5 times. I don't use a watch, using a mental count, which is why I say "20 to 30". If making a kit I degas then add the kieselsol while the wine is swirling and cover the fermenter with a towel. An hour later I add the chitosan, stir a bit to mix, then rack back into the carboy.

My current philosophy on degassing is that it's a good idea, as the wine clears faster and I get gross lees out sooner. People focus on O2 exposure, but the wine is emitting so much CO2 that O2 is not an immediate problem. However, in succeeding rackings I'm careful of O2 exposure as the bulk of the CO2 is expelled.
 

Doug’s wines

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While I would like to know how old this wine and how many rankings it’s had etc to make a proper recommendation, without that context - Yes. Degas again. Funny I just posted this advice on the advice for newbies thread
:wy
Sounds like you are moving quickly to bottle a younger wine, maybe from a kit? I used to do that myself, and if I didn’t fully degas I would need to open the bottle at least an hour before I drank it and decant it. I found off aromas if I didn’t. I ended up dumping a couple of full batches, degassing and rebottling, MUCH better wine even if it was a pain. Sav Blanc is SWMBO’s favorite and I’ve mistakenly bottled a batch that wasn’t fully degased. Ever since she checks when she opens and reports on whether it was degased well or not (sigh).

Now If this wine is a 6months to a year old, and has been racked several times, well then that is probably different situation at which point I would put some in a small bottle, put the finger over the top, shake it, pulll my finger off and if it pops like opening a Coke, then degas.

Yes commercial wines have residual co2, but those wines are usually bulk / barrel age for months to years and didn’t move from ferment to bottle in 8-12 weeks like many kit makers do. There’s a lot more gas that comes out naturally over successive rankings and general bulk aging ensures aromas and other things soften a lot too.
If I was going to bottle quickly, I would overdo it on the degassing. O2 exposure at early stages is actually better for the wine IMO so I would be less concerned about that in the first 2ish months).
 
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I agree with @Rice_Guy. Even with degassing, wine can continue to expel CO2 for days or weeks. Plus changes in air pressure and temperature will affect the airlock.

When degassing I probably do 20 to 30 seconds, changing direction 5 times. I don't use a watch, using a mental count, which is why I say "20 to 30". If making a kit I degas then add the kieselsol while the wine is swirling and cover the fermenter with a towel. An hour later I add the chitosan, stir a bit to mix, then rack back into the carboy.

My current philosophy on degassing is that it's a good idea, as the wine clears faster and I get gross lees out sooner. People focus on O2 exposure, but the wine is emitting so much CO2 that O2 is not an immediate problem. However, in succeeding rackings I'm careful of O2 exposure as the bulk of the CO2 is expelled.
Interesting that the temp and pressure will affect the air locks. I never thought of that. With that in mind over the last week the temp of my basement has risen 2 degrees and we have had on and off rain. Thanks.
 
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While I would like to know how old this wine and how many rankings it’s had etc to make a proper recommendation, without that context - Yes. Degas again. Funny I just posted this advice on the advice for newbies thread
:wy
Sounds like you are moving quickly to bottle a younger wine, maybe from a kit? I used to do that myself, and if I didn’t fully degas I would need to open the bottle at least an hour before I drank it and decant it. I found off aromas if I didn’t. I ended up dumping a couple of full batches, degassing and rebottling, MUCH better wine even if it was a pain. Sav Blanc is SWMBO’s favorite and I’ve mistakenly bottled a batch that wasn’t fully degased. Ever since she checks when she opens and reports on whether it was degased well or not (sigh).

Now If this wine is a 6months to a year old, and has been racked several times, well then that is probably different situation at which point I would put some in a small bottle, put the finger over the top, shake it, pulll my finger off and if it pops like opening a Coke, then degas.

Yes commercial wines have residual co2, but those wines are usually bulk / barrel age for months to years and didn’t move from ferment to bottle in 8-12 weeks like many kit makers do. There’s a lot more gas that comes out naturally over successive rankings and general bulk aging ensures aromas and other things soften a lot too.
If I was going to bottle quickly, I would overdo it on the degassing. O2 exposure at early stages is actually better for the wine IMO so I would be less concerned about that in the first 2ish months).
Thank you. Not a kit. Juice. I started in April timeframe. Racked from primary fern to carboy. Then again to degas and clarify. Then this last time to sit. Looking to bottle in September.
 

Doug’s wines

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Thank you. Not a kit. Juice. I started in April timeframe. Racked from primary fern to carboy. Then again to degas and clarify. Then this last time to sit. Looking to bottle in September.

5-6 months months is a good batch window for sauv blanc bottling. Yes atmosphere will cause burbling air locks or popped stoppers. Had an air cond go out and the heat popped a stopper across the room on a fully degassed batch. Heard the pop and thought someone was shooting at me.

Reread your post and saw the “pressure, not burbling” so most likely just that.

Personally I would leave it alone now, splash rack it a bit on the start of the last clarifying rack before bottling. If it shows a lot of gas at that point then worry about it. likely if there is gas, it will depart during the next few months.

All the best
 
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5-6 months months is a good batch window for sauv blanc bottling. Yes atmosphere will cause burbling air locks or popped stoppers. Had an air cond go out and the heat popped a stopper across the room on a fully degassed batch. Heard the pop and thought someone was shooting at me.

Reread your post and saw the “pressure, not burbling” so most likely just that.

Personally I would leave it alone now, splash rack it a bit on the start of the last clarifying rack before bottling. If it shows a lot of gas at that point then worry about it. likely if there is gas, it will depart during the next few months.

All the best
Thank you, I will keep an eye on it!
 
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