VacuVin question

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A couple recent threads got into this and I could use some clarity on the subject. When d gassing with a VacuVin type pump is it needed to let the CO2 that rises to surface to dissapate naturally, leaving the bung/vinstopper in place?
Or can you release the bubbles quickly by breaking the seal, then allowing the space to pump out more CO2 repeatedly until needed?
I drill beforehand, but even still, "All natural" fizz dissipating seems like it could take days or weeks. Am I jeopardizing anything by breaking seal to let it escape?
 
Hope this will help answer your question(s)...

I've been doing VacuVin degassing for almost four years. I don't release the vacuum until I'm done with the process. When I first start the process I might pump only a dozen times and then have to stop and let the foam/froth subside. After awhile I can pump 50 times or more then give my muscles a short break and pump again. If you've got wine up into the neck you might only get by with 2-3 pumps before you need to stop and let the foam settle.

IMHO, continually breaking the seal just lets O2 into the carboy for no benefit that I can think of, but probably does no damage to the wine. Maybe you just get your degassing done in a little less time? But then again maybe longer because you need to pump more to reestablish the vacuum?
 
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I have only VacuVin degassed once, but I thought it was highly effective and I'll be doing it that way for future batches.

When I did it, I pumped until all the foam came up, and I broke the seal. This seemed to let the CO2 escape faster and I could commence to pumping again...and again....and again.

That's what I did...pump, break seal, dissipate...pump, break seal, dissipate...pump, break seal, dissipate.

If that's bad, I'd like to know as well.
 
This would be a great question for a Chemist or Scientist who understands how gas binds and releases in a liquid under a vacuum. Not being one, here's my thinking. Breaking the seal likely lets the CO2 escape before it has a chance to go back into solution. Since you pump right away again after the release you are pulling out most of the oxygen you let in so there shouldn't be a risk of adding too much oxygen there. I don't see a significant risk in breaking the seal to speed up the process.

My primary unknown is what affect a sudden vacuum release has on CO2 and it's potential for reabsorption back into solution. I don't think it's high, but I don't know.
 
Knowing when to stop degassing is another question I'd like answered. I stop when I start getting the larger bubbles AND the pumping gets noticeably harder. Concerned that at some point if I keep going I'm just doing a vacuum boil and not getting out anymore CO2.
 
Henry's Law holds that the amount of gas that would be dissolved in equilibrium is directly proportional to the partial pressure of that same gas in the headspace. It is fairly accurate at low concentrations. Therefore, at equilibrium, you are better off breaking the seal to replace the CO2 in the headspace with N2/O2 to (slightly) reduce the CO2 partial pressure.

HOWEVER, I cannot imagine it is worth it. You just did all of that work to reduce the overall pressure. It seems to me that you would be better off not re-doing that work on the new headspace, but rather to put your efforts into additional pumping on the partially evacuated headspace.
 
Some people on this forum are just so smart it makes my head hurt!
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[Unforunately I'm not one of them.]
 
Henry's Law holds that the amount of gas that would be dissolved in equilibrium is directly proportional to the partial pressure of that same gas in the headspace. It is fairly accurate at low concentrations. Therefore, at equilibrium, you are better off breaking the seal to replace the CO2 in the headspace with N2/O2 to (slightly) reduce the CO2 partial pressure.

HOWEVER, I cannot imagine it is worth it. You just did all of that work to reduce the overall pressure. It seems to me that you would be better off not re-doing that work on the new headspace, but rather to put your efforts into additional pumping on the partially evacuated headspace.

Ummm.....seriously not trying to be an *** here, but can you break that down for me in a slightly more simple manner?

Are you saying that breaking the seal will have no positive effects, and that it is just better to keep it under vacuum?
 
Henry's Law holds that the amount of gas that would be dissolved in equilibrium is directly proportional to the partial pressure of that same gas in the headspace. It is fairly accurate at low concentrations. Therefore, at equilibrium, you are better off breaking the seal to replace the CO2 in the headspace with N2/O2 to (slightly) reduce the CO2 partial pressure.

HOWEVER, I cannot imagine it is worth it. You just did all of that work to reduce the overall pressure. It seems to me that you would be better off not re-doing that work on the new headspace, but rather to put your efforts into additional pumping on the partially evacuated headspace.

Thanks, I had you in mind when I wrote my reply but didn't want to ask specifically. I appreciate the information.
 
I'm thinking he means letting the new CO2 fizz sit at he top in a vacuum and dissipate naturally has some pressure down back into the wine anyway....... wait. He's saying the opposite.
No. He's saying both.
And repeatedly putting the entire batch on the vacuum pressure, rather than leaving the pressure and have minimal pumping each time, is more beneficial????

His conclusion is not to break the seal
But doesn't seem to be a huge deal if we did. I don't know what he means with "equilibrium" here.
 
I just read up on Henry's law on wiki and got some more clarity on his reply.
To put it in a way for us simple folk' :

Breaking the seal might be more beneficial so the CO2 doesn't dissolve back into the wine just sitting there at the top. But it would be minimal anyway and, in his opinion, isn't worth speeding up the process because it requires a substantially more amount of elbow grease pumping for the whole batch every time. ---- I think.

I was concerned with oxygen originally. Though it seems either way is not doing enough to jeopardize the wine in any way. .....: we just gotta make sure we don't keep going after all the CO2 is out! Bigger Bubbles= walk away.

Feel free to correct me if I'm wrong please
 
If your wine stops bubbling and you are holding a vacuum it suggests that all the gas you are going to get out with that amount of vacuum has been pulled out. Breaking the seal if you are still getting getting bubbles is pointless - Unless you are getting a lot of foaming then I can see why you might stop pulling more vacuum. BUT breaking seal - just as Sour Grapes states, get you nothing other than a sore arm. The only thing that will get more gas out than what you have pulled out is more vacuum. As long as there is a vacuum, there's space for more gas. Now if your vacuum disappeared (Without breaking the seal and instead you got a positive pressure situation THEN you need to break that seal quickly and let that gas out.
 
Maybe we've strayed from the original question. "Breaking the seal" -meaning pinching the Vinstopper to allow the newly surfaced CO2 that is all fizzed up nearly touching the bottom of the bung to be removed (assuming the CO2 is escaping the carboy and not going back into the wine. For the purpose of making space for pumping more CO2 out directly after. And repeating. Pump. Squeeze. Pump. Squeeze. Pump. Squeeze. Etc. leaving the last one under vacuum and CO2 fizz dissipating naturally. OR Until no more CO2 is surfacing. Then putting my airlock back on.
With a stubborn batch that is pretty full sometimes it only takes a few pumps to fill the headspace with CO2 fizz again. And basically inquired if waiting the 10 -20 min dissipation time between pumping is the same as breaking the seal to pump more directly after. I'm not trying to "get more gas out then what I have pumped". I'm trying to pump gas out more time efficiently.
Releasing the vacuum is just a byproduct of clearing fizz from headspace in this case. Not the endproduct.
 
Highly unlikely that CO2 would go back into the wine, while a vacuum exists. Open a bottle of soda, drink a bit and then cap it. leave it on the counter a couple of days and it goes flat - all the CO2 in the soda has left even without a vacuum. When you pull a vacuum you are creating a situation where CO2 cannot readily remain dissolved in the wine, until that vacuum is broken the CO2 is going remain out of the wine unless a condition arises to remove the vacuum and put the wine under pressure - THEN CO2 could conceivably dissolve back into the wine. That's why soda are bottled under pressure. For the same reason a cold soda is less likely to spew forth on popping the top than a warm soda. The cold soda has a lower pressure state in the container.

Now if conditions exist within the wine to create more CO2 then vacuum or no vacuum the CO2 is going to build up. Normally once fermentation is done, CO2 Generation stops and we just have to either give it time to leave the wine must OR pull it out with a vacuum and warmer temps will help that process.

I am gathering that the concern is that their isn't enough free space in the carboy for all that CO2 but that's not an issue as long as there is a state of vacuum in the carboy. IF you left that carboy in a state of vacuum for a week and the seal leaked or the CO2 amount increased to the point that the vacuum was gone - an equilibrium was reached - Then it might be possible for CO2 to re-dissolve into the wine. Not a likely prospect but possible I suppose.
 
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IF you left that carboy in a state of vacuum for a week and the seal leaked or the CO2 amount increased to the point that the vacuum was gone - an equilibrium was reached - Then it might be possible for CO2 to re-dissolve into the wine. Not a likely prospect but possible I suppose.


You just hit on something that I've never heard mentioned before. Or maybe I just have never realized. The alternative to what I have been doing is to pump for a vacuum, and then leave under vacuum for about a week? Which then allows the CO2 to release over this time. Instead of trying to just pump it all out.
With what you stated I'm deducing that this sounds like the proper way and I just simply did not know this was the way. Many thanks
 
You just hit on something that I've never heard mentioned before. Or maybe I just have never realized. The alternative to what I have been doing is to pump for a vacuum, and then leave under vacuum for about a week? Which then allows the CO2 to release over this time. Instead of trying to just pump it all out.
With what you stated I'm deducing that this sounds like the proper way and I just simply did not know this was the way. Many thanks

I'm guessing that the success or failure of what you're proposing would depend on several variables... Like the amount of head space, temp of the wine, how much vacuum you pulled. Again, just guessing.

I favor pumping it out sooner then later and moving onto the next step or phase in making the wine.
 
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I'm guessing that the success or failure of what you're proposing would depend on several variables... Like the amount of head space, temp of the wine, how much vacuum you pulled. Again, just guessing.

I favor pumping it out sooner then later and moving onto the next step or phase in making the wine.


Understood. But Regardless of variables, I was entirely unaware. I only previously thought that I should only b leaving it under the vacuum to let the pumped CO2 fizz dissipate. Not realizing the vacuum is still degassing even after the fizz is gone.
 
Interesting topic...One of the suggested ways to de-gas is racking......which, I think, exposes the wine to oxygen during the process. I normally rack every two-three months before I bottle (one year in bulk storage) and use a hand brake bleeder vacuum a few times as well.
 
I'm guessing that the success or failure of what you're proposing would depend on several variables...


The can of worms is way open now! I'm not proposing anything. Just trying to know the correct way to do this. The VacuVin is a bottled wine 'saver'; not a winemaking degasser. Understood. It just happens to multifunction, unintentional by the maker yet convenient. So I fully realize there is no "by the book" method given that there is no book. And minimal oxygen exposure was what was originally appealing to me.
Degassing is not a major issue now nor has it ever been. I usually would just let time do the work. And I have hand-whipped, drilled, pumped and combos of these. Starting kits is what has brought this into the light for me.
My original question was asked with the mindset that there was only 2 possible ways to use this tool , neither of which involved letting the carboy remain under vacuum after the Co2 fizz had dissipated. Also curious If using the AIO is similar in terms of pulling a vacuum and let it dissipate and repeating, and after this then leaving carboy under the vacuum for a few days?

I've never been actually shown the 'proper' way to degas with VacuVin. Obviously there are 9 ways to skin a cat. And I've looked up videos but none are too detailed and each person has slightly different ways. Basically my new question has morphed to "when vacuum degassing(with any tool that gives a sealed vacuum) is it proper procedure to leave wine sit under vacuum for an extended time period after the remaining fizz has gone?"
 
9 ways to skin a cat is a great response. Couple of things to add. Isn't using a hand siphon the same as an AIO just not as safisticated. It's still a vacuum by gravity. Secondly and a different topic, does vacuum pumping also release the free sulfites as well?
 

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