Wine Vacuum Degassing with Pump

[scott565]

Hi All,

New to the forum, I am looking for clarification(no pun!) on degassing with a vacuum pump. I have read most of the posts on the topic but I have some questions:

To pump and degas into an empty carboy, some want to splash rack, and others want to extend the racking tube to the bottom of the destination carboy.
If I want to degas using the pump and pinched hose setup, will the extracted CO2 infiltrate the wine if the racking tube goes all the way to the bottom of the empty carboy? Will the wine absorb oxygen if splash racked?

Is there any difference in this process when racking a red or white wine?


Thanks much!
-Scott

 

[robie]

Hi All,

New to the forum, I am looking for clarification(no pun!) on degassing with a vacuum pump. I have read most of the posts on the topic but I have some questions:

To pump and degas into an empty carboy, some want to splash rack, and others want to extend the racking tube to the bottom of the destination carboy.
If I want to degas using the pump and pinched hose setup, will the extracted CO2 infiltrate the wine if the racking tube goes all the way to the bottom of the empty carboy? Will the wine absorb oxygen if splash racked?

Is there any difference in this process when racking a red or white wine?


Thanks much!
-Scott

I assume the "pinched hose setup" is where the hose is actually pinched to create a sort of spewing or bubbling at that point. I have never used that technique and likely never will. Seems it would infuse a lot of air into the wine at that critical point. To me it is taking a chance, especially for whites.

For reds, letting the wine splash into the receiving carboy helps release more CO2. Of course it also allows a lot of air into the wine. It works great if you have any H2S (rotten egg smell) in the wine.

For whites, I would not splash rack just to degas, unless you have an H2S issue.

The actual process of racking will help release a lot of CO2, whether you splash rack or let the tube go all the way to the bottom. As the CO2 surfaces, the vacuum pump will draw it away. You need to be mindful of allow too much oxygen into your wine. This is even more of an issue for whites.

 

[GreginND]

Actually I usually splash rack every time. That is, I have a small tube that goes into the receiving carboy and don't have a racking tube extend to the bottom. I don't worry about oxygenation doing this because the carboy is under vacuum! At reduce pressure it is more difficult for the oxygen to dissolve into the wine. No, it's not completely evacuated and oxygen free but I don't think it is that much of an issue. One of the benefits of vacuum transferring. I wouldn't splash rack if I were using normal pressure siphoning or pumping.

 

[Chiumanfu]

Although the "pinched hose" setup works extremely well, I have stopped using it for the following reason.

The pinched hose causes a venturi. The wine travelling through the venturi is accelerated very fast and the vacuum increases as well. The vacuum can easily exceed the level where ethyl alcohol and all sorts of stuff boils at room temp. Who knows what is being flash vaporized in that short section of hose. Probably in reality it makes little to no difference, but the math is there to support it so I don't use that method any more.

 

[vacuumpumpman]

Actually I usually splash rack every time. That is, I have a small tube that goes into the receiving carboy and don't have a racking tube extend to the bottom. I don't worry about oxygenation doing this because the carboy is under vacuum! At reduce pressure it is more difficult for the oxygen to dissolve into the wine. No, it's not completely evacuated and oxygen free but I don't think it is that much of an issue. One of the benefits of vacuum transferring. I wouldn't splash rack if I were using normal pressure siphoning or pumping.

I agree ^^

 

[scott565]

Thanks everyone for taking the time to respond. Interesting points by all. At some point I am going to split up a kit into 4 parts and do parts with splash and no-splash racking plus each of those variations with and without a clamp on the hose.
Chiu - I understand your concern about boiling alcohol and other stuff, I wonder if we could measure that effect just using a hydrrometer before and after racking. I would expect a sg change if any substantial amount of alcohol was lost in the process. Has anyone tried that?
Has anyone ever attributed a sub-par kit result to splash racking or using the clamped hose to draw out the CO2?
I see lots of concerns and potential for problems, but no one seems to say they spoiled their kit this way.

Thanks again, everyone! I really appreciate everyone sharing their knowledge and experience!
-Scott