Degassing in a carboy....

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So the real question would be - how would you know when you have removed the CO2 from your wine using this method and not transferring under vacuum ?

From my kit wine days, it's pretty simple. Starting with a wine at the appropriate temps for degassing, 75F - ish, when the little bitty CO2 bubbles quit coming out of solution and are replaced by the bigger bubbles that Paul refers to above, the wine is degassed. Normally in just a few minutes this occurs. You can easily be confirm the presence or absence of CO2, regardless of how you degas, (vacuum pump, whipping, multiple AIO rackings, etc.) by the "poof test" or a simple tasting of the wine for confirmation.

Today, in practice, since I only do grape wines, degassing is no longer an activity in my winemaking, as my wine sits for years in barrels and there's no chance of CO2 making that journey.
 
thanks Johnd,
I felt the same way about the size if the bubbles that were forming.

if you look in the picture that is in question - it shows large bubbles and no regulator and degassing for 60-90 minutes.

I don't want the new Winemaker thinking this is a normal procedure - unless we can confirm that it is ?

And making sure that it is a safe practice also (added after initial post )
 
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I am not sure where the idea that ethanol does not dissolve CO2 is coming from. Ethanol can dissolve about 3 times as much CO2 as water can.

But back to thinking about the liquids: Again, you can evaporate a liquid without boiling it. So, yes, I agree that if you remove the partial pressure of water and/or alcohol in the headspace, you will evaporate water and/or alcohol from your wine. Again, this could be done with a vacuum pump, or it could be done by leaving a glass of wine on your kitchen counter on a warm, dry day. You don't need to see a bubble for evaporation to happen.

Now, let's think about what it should mean if you DO see a bubble. Does that mean it is alcohol? No, it doesn't. Let's do a thought experiment. Imagine you have a bottle of pure ethanol, and you are drawing a vacuum on it, but you are at a pressure/temperature combination that is below the boiling point. The atmosphere (i.e., the headspace) will be full of ethanol vapor. Now, let's say an omnipotent being freezes time, goes into the bottle, and injects a bubble of pure ethanol vapor, then restarts time. What will happen to that bubble? Answer: it will collapse, and the vapor will re-condense into the liquid phase. It will not rise up to the surface. The vapor pressure of the ethanol inside the bubble is not high enough to withstand the pressure that the liquid exerts on it, so it collapses. (The definition of boiling is when the vapor pressure is high enough that the bubble does not collapse.)

So, in the real world, if you see a bubble during degassing (and you are not boiling the whole vessel) it is not a bubble of alcohol. It was some dissolved gas coming out of solution.
Good science!
over all I laugh at some of the above with “are we trying to count the number of angels that can dance on the head of a pin”
* It is normal to have some CO2 in our wine/ grain alcohol/ soda that has sat on the counter over night/ etc. The question should be does it matter? My answer is if it is high enough to change the hedonic quality yup, example 2 atmospheres of CO2 in soda will change the pH about 2 lower, we flavor profile this as tingly/ acidic/ carbonic so it matters, positively if it is soda or champagne and negatively if it is still wine and we don’t want a cork popping off.
* it is normal to have a variety of molecules come off in any evaporation. If I was running a vacuum still collecting vitamin E yup I also collected a good slug of fatty acids and triglycerides. Same if we have vacuum with alcohol. I know it is there but did it matter?
* with degassing in a vacuum yup it goes fast and yup when I started on an empty carboy I was saturating with oxygen at maybe 5 or 10 inches Hg, , when the carboy is full the atmosphere can be assumed to be saturated CO2 so at that point we know it doesn’t matter.
* All process systems are dynamic, wine is a dirty environment (ex the solids in wine will decrease solubility of CO2 by a few ppm) . YES there is CO2 in ALL naturally occurring wines even if it has been run through a AI1 3 times or 300 times. , , , and if it doesn’t change the flavor it didn’t matter. At some point the risk from oxygen exposure by another trip through the vacuum degassing is greater than the gain so we stop.
I may be lazy with a cup of coffee ant the tv on so 90 minutes is nothing or I may hook a $10 vacuum pump from amazon up and let it run over night and again the time means nothing, , , compared to the effort of sanitizing a carboy, sanitizing tubing and knowing that a few ppm of O2 was added as I started the operation.
 
thanks Johnd,
I felt the same way about the size if the bubbkes that were forming.

if you look in the picture that is in question - it shows large bubbles and no regulator and degassing for 60-90 minutes.

I don't want the new Winemaker thinking this is a normal procedure - unless we can confirm that it is ?

I can't say that I ever have, or would, vacuum my wine that long, but still don't believe that even that would remove any appreciable amount of alcohol from the base wine, sure would be interesting to know............
 
Thank you ,

So if I took vacuum to it - I will probably not pull much if any co2 from it - correct ?

I wonder what the percentage of co2 in young wine that not has been degassed of the CO2
The technical answer is that the CO2 is in equilibrium with the wine.

If I went to Henry’s law the solubility = K(constant) X partial pressure

Partial pressure = atmospheres X percentage

* Therefore on a new wine which is degassing there is back pressure on the air lock and the percent of CO2 could be close to 100 percent and we could guess that the the wine is saturated with 1 atmosphere of CO2.
* the magic of any vacuum pump is that it will decrease the atmospheres of pressure and we push the equilibrium lower (linear with the % vacuum, per formula above)
* The magic of running through a vacuum transfer is that the droplet size is reduced (significantly below 5 gallon) therefore we can assume that we are in equilibrium as stated by the gas law, now and at every instant time. The wine will seek the same equilibrium with atmospheric pressure but get to equilibrium faster.
* Steve I don’t like calc enough (dynamic system modeling) that I lay awake at night wondering but the engineering profs train us to know what the dynamic processes are and then consider risk/ benefit.
For talking with vacuum customers (or a boss with a marketing degree) the key thing to get say is that “the effect is linear with the pressures”, , , , so talking in percent of atmosphere is easy to understand.
 
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I can't say that I ever have, or would, vacuum my wine that long, but still don't believe that even that would remove any appreciable amount of alcohol from the base wine, sure would be interesting to know............
That is one of the main reasons that we developed the allinonewinepump.
To safely remove the CO2 without putting the carboy at risk of excessive vacuum pressures.
 
if you look in the picture that is in question - it shows large bubbles and no regulator and degassing for 60-90 minutes.

This may be the source of miscommunication. I certainly did not think that picture was taken after an hour of degassing. I think @Carboy-Boy was demonstrating the "explosive" phase early in the process. @Carboy-Boy , can you clarify?

To safely remove the CO2 without putting the carboy at risk of excessive vacuum pressures.

I have never understood the thinking behind this, which you read often here on WMT. This is just like saying "I'll park a 5000 pound truck on my driveway, but I'd never park a 5800 lb truck there! Don't want to crack that driveway!"
 
So the real question would be - how would you know when you have removed the CO2 from your wine using this method and not transferring under vacuum ?
There will be essentially the same ppm of CO2 in both cases.

My experience , and apparently yours , is that a regulator is valuable so I don’t create a mess of froth and spend an afternoon cleaning the pump head out.
 
There will be essentially the same ppm of CO2 in both cases.

My experience , and apparently yours , is that a regulator is valuable so I don’t create a mess of froth and spend an afternoon cleaning the pump head out.
I believe you forgot to add the content where that was intended for.

Here is the beginning of it =

Comparing types of degassing methods and effectiveness


I only wanted to prove that taking full vacuum on a carboy for 60 -90 minutes. That you are not still removing CO2 from the wine.

So the real question would be - how would you know when you have removed the CO2 from your wine using this method and not transferring under vacuum ?
 
I just can't get over that 60-90 minutes time frame. Not sure I would want to expose my wine to that pressure for that long. I think I'll stick with racking 3 or 4 times with a vacuum pump and being generous a total of 15 minutes and there is no more CO2. With appropriate levels of SO2, I don't worry about the Oxygen that may get in (and some say it's good for it to get into the wine). Each to their own.
This isn’t pressure, it is vacuum.

If you are not willing to expose you wine to a vacuum For 90 minutes, you should never use a hand pumped ‘vacuum wine preserver’ (mine will pull -0.5 atmosphere) for a week in the fridge or a “Headspace eliminator” (the suction bulb ‘indicator’ will suck in at -0.16 atmosphere) for a month in a carboy.

? ? I thought vacuum was accepted ? ?
 
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This isn’t pressure, it is vacuum.

If you are not willing to expose you wine to a vacuum you should never use a hand pumped ‘vacuum wine preserver’ (mine will pull 0.5 atmosphere) or a “Headspace eliminator” (the suction bulb ‘indicator’ will suck in at 0.16 atmosphere)
? ? I thought vacuum was accepted ? ?
Let's please not try and nic pick , not all of us use all the same type of language

He did say he uses a vacuum pump to degass as he is transferring - correct ?

This was taken from Google

Vacuum units can be defined in two ways. In common language, it is taken as negative pressure below standard atmospheric. Units commonly used are mm of Hg, or inches of Hg below this reference.


Notice negative PRESSURE IS USED
 
I believe you forgot to add the content where that was intended for.

Here is the beginning of it =

Comparing types of degassing methods and effectiveness

So the real question would be - how would you know when you have removed the CO2 from your wine using this method and not transferring under vacuum ?

The gas law does not care if you are vacuum racking.

The equilibrium level of CO2 will be the same. The difference in the two methods is the size of particle/ droplet permits us to assume that we reach equilibrium essentially instantly if we create droplets. If we reduce pressure such that foam isn’t a big issue we have larger particles (1/4 inch stream) and we know we aren’t actually at equilibrium and the eventual equilibrium we are working against is located at roughly 0.5 atmosphere.
In the scheme of things commercial folks find that an equilibrium based on 1.0 atmosphere is good enough, , , so it again says the main gain is time.[/QUOTE]
 
This isn’t pressure, it is vacuum.

If you are not willing to expose you wine to a vacuum you should never use a hand pumped ‘vacuum wine preserver’ (mine will pull 0.5 atmosphere) or a “Headspace eliminator” (the suction bulb ‘indicator’ will suck in at 0.16 atmosphere)
? ? I thought vacuum was accepted ? ?

Yes, sorry, I used the wrong word. It happens, I believe the intent of what I said is still valid. I will say I don't even own a wine preserver, bottles opened are consumed around here. I do use headspace eliminaters, but there is a significant difference, I very seldom get any bubbles coming out of suspension after I turn off the pump and really don't get many when I first vacuum it up. I'm not at all against vacuums, but the amount of vacuum plus the time involved seems to be not a good combination. And I think we may have beaten this horse well past it's usefulness.
 
I think that’s nitpick, with a “t”, not a “c”..................

Ok - whos going to be the grammar police here ?

Just take me in now ! ! Big fingers and small keyboards ( or worse yet the PHONE )
 
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