vacuum degassing and air/head space

[shanek17]

If i was to create a vacuum in a glass carboy to degas my wine are there any worries or problems to consider? More specifically im talkjng about the headspace in the carboy. i remember reading somewhere on this forum about possible glass carboy implosions because of the amount of headspace during degassing. i had no luck finding this info so maybe someone can clarify.

 

[Ernest T Bass]

I'm new to this wine making also and no expert on anything, but here is how I so it.
When degassing I like to have 4 or 5 inches of head space, this gives me a little room if it really foams up fast. Start with no vacuum and slowly increase the vacuum while watching the carboy, if it starts to foam up close to the top of the carboy, decrease the vacuum. You aren't going to hurt your wine with the increase head space because you are covering the wine with CO2. Continue to degas until you get almost all the CO2 out, you'll see real fine bubbles rising every once in a while. When you stop degassing slowly decrease the vacuum so that you don't get a surge of air in the carboy. That's good, you want a little CO2 left in the carboy, not much, just enough to cover the wine after you have topped it off. After degassing I top it off with the same kind of wine or something very close to it. Top off to about an inch of head space. There are other ways and probably better ways, but that's the way I do it.
Semper Fi
Bud

 

[vacuumpumpman]

I personally like to splash rack while doing a vacuum transfer - which means that the racking tube is aprox 1/2 the height of the carboy causing turblence under vacuum forcing the co2 out of the wine using vacuum.

I'm new to this wine making also and no expert on anything, but here is how I so it.
When degassing I like to have 4 or 5 inches of head space, this gives me a little room if it really foams up fast. Start with no vacuum and slowly increase the vacuum while watching the carboy, if it starts to foam up close to the top of the carboy, decrease the vacuum. You aren't going to hurt your wine with the increase head space because you are covering the wine with CO2. Continue to degas until you get almost all the CO2 out, you'll see real fine bubbles rising every once in a while. When you stop degassing slowly decrease the vacuum so that you don't get a surge of air in the carboy. That's good, you want a little CO2 left in the carboy, not much, just enough to cover the wine after you have topped it off. After degassing I top it off with the same kind of wine or something very close to it. Top off to about an inch of head space. There are other ways and probably better ways, but that's the way I do it.
Semper Fi
Bud

 

[shanek17]

I personally like to splash rack while doing a vacuum transfer - which means that the racking tube is aprox 1/2 the height of the carboy causing turblence under vacuum forcing the co2 out of the wine using vacuum.

Oh so your using the racking tube to agitate the wine will under vacuum pressure? How can that be done? iv heard others mention they wish they could agitate the wine when vacuum degassing, but you must have some type of nifty setup to do it.

 

[shanek17]

So does anyone have any information about possible exploding carboys? Does it really matter how much head space is in the carboy? I just wouldnt want to try vacuum degassing and have a big carboy explode , because i didnt have enough or too much wine in carboy.

 

[vacuumpumpman]

I personally never heard of a carboy imploding, I personally had a carboy under 29 in hg for approx 45 minutes while it shook violantly because it was actually boiling water at that time and nothing happened.
I do not recommend anyone else trying this.
Please google carboy imploding as I have several times and found nothing , unless there was a previous crack and it did not implode all it did was loose vacuum and spill wine

 

[shanek17]

I personally never heard of a carboy imploding, I personally had a carboy under 29 in hg for approx 45 minutes while it shook violantly because it was actually boiling water at that time and nothing happened.
I do not recommend anyone else trying this.
Please google carboy imploding as I have several times and found nothing , unless there was a previous crack and it did not implode all it did was loose vacuum and spill wine

Yes ill have to look more into this. in the mean time wade has this to say about it. he mentions having little head space in the carboy. why, i do not know...ill have to ask him.

*"How to degas your wine with a vacuum pump

When degassing your wine with a vacuum pump you need to use a glass carboy that is topped offWhen using a vacuum pump you want to have the vacuum all the way off when starting and slowly move it up to around 10" and then let it run for a few minutes. If you notice at any time the wine or foam approaching the bung or carboy cap you are using then immediately back off on the vacuum to let the foam go down and then slowly increase again. Once you can get it up to around 18-20" and hold it there without an eruption your wine is degassed. You should also notice that when starting to degas your wine the bubbles are very small and abundant but towards the end the bubbles are less frequent and much bigger, this is a visual tell tale that you are or almost done. Also, when done degassing always either shut your pump down and let all pressure out before trying to remove the bung or just turn the knob down all the way and wait until the gauge reads 0.*"

 

[tonyt]

Oh so your using the racking tube to agitate the wine will under vacuum pressure? How can that be done? .

That is vacuum racking from one carboy to another. Not vacuum degassing. While vacuum racking you are actually pulling gass out. The splashing into recieving carboy releases more gass. Smart people will chime in.