Degassing in plastic carboy

[canerak]

I want to degas my wine with a vacuum pump.But when i pump out the air, the carboy shrinks like in the photo and no CO2 come out of my wine.
If i use a glass carboy for this, can i suck out CO2 or is there another posible reason for not degassing?
Thank you..

 

[bernardsmith]

Looks like the walls of this carboy are insufficiently rigid for you to create a vacuum to pull out the CO2. What you might do - despite you wish to use a pump to make a vacuum, is to attach a stirring rod to a hand drill and use that to stir the gas out. You might want to raise the temperature of the carboy a few degrees while you stir: the warmer the liquid, the less gas it can hold, but you do not want to cook the wine - If you raise the temperature to about 75 F for the few minutes you are stirring (not whipping , but stirring- you do not want to fold air into the wine).