Degassing with All-In-One

[Elmer]

I used the AIO to attempt to degass a gallon of wine, which I am having trouble clearing.
Normally I would just rack back and forth, but this time did not have a clean vessel .

My usual process is to attach the vacuum tube to a rack tube. Putting a stopper at end of the racking cane.
Yesterday I turned on the AIO and let the bubbles and foam rise. When the foam got too close to stopper I hit the release valve and repeated.
I did this for close to 20 min and the bubbles never subsided.
Is there a point where you begun creating the bubbles and are no longer degassing.
After one of my few brakes (I don't like to leave AIO running for too long) I began pulling big bubbles.

Is the size of the bubble an indicator ?

 

[dralarms]

Well, do that if you like but the way the AIO is designed it works to degass by splash racking under vacuum. I'm not afraidof damaging the AIO, it just works better to use it the way it was designed.

 

[vacuumpumpman]

I'm new to wine making - been doing it less than a year. However, I've been fermenting a gallon of everything that I can get my hands on and leaving it to bulk age.

When it came time to degas, I figured that I would first try the cheap route and bought a brake bleeder. I spent all day degasing one gallon while working from home one day and my hand hurt like h*ll. Learned my lesson.

So I bought an AIO - an early Xmas present for myself. Steve was incredibly helpful with a few questions that I had prior to making my purchase - and a few more that I had after I bought it. But the real proof was today.

I racked a gallon of cherry back and forth from its original carboy to a clean carboy 4 times in about 4 minutes total. I thought that there was no way that my wine was fully degased. So I got out my brake bleeder and pumped it. Some foam appeared, I released the vacuum, pumped it again, and then waited. A few tiny bubbles came up, but the vacuum held at 25 psi.

I am glad you are enjoying your wine making !!

 

[sour_grapes]

Rich and bkisel: The whole volume of the wine is "aware" of the reduced isostatic pressure. Thus, as bkisel points out, you can get bubbles forming anywhere within the volume of the wine. However, the bubbles need to nucleate, that is, they need to reach a certain size, which favors their continued growth, rather than their dissolution back into the gas. The size where continued growth is favored over dissolution depends on both how much CO2 is dissolved, and what the isostatic pressure is. Bubble formation is greatly aided if there is a "nucleation point," that is, some asperity where the nascent bubble can get started.

I believe that Rich is correct, however, that gas near the surface can escape more easily; in this case, the nucleation of a bubble is not required. Rather, gas can diffuse directly from the liquid into the gas phase, without nucleating a bubble.

 

[bkisel]

Rich and bkisel: The whole volume of the wine is "aware" of the reduced isostatic pressure. Thus, as bkisel points out, you can get bubbles forming anywhere within the volume of the wine. However, the bubbles need to nucleate, that is, they need to reach a certain size, which favors their continued growth, rather than their dissolution back into the gas. The size where continued growth is favored over dissolution depends on both how much CO2 is dissolved, and what the isostatic pressure is. Bubble formation is greatly aided if there is a "nucleation point," that is, some asperity where the nascent bubble can get started.

I believe that Rich is correct, however, that gas near the surface can escape more easily; in this case, the nucleation of a bubble is not required. Rather, gas can diffuse directly from the liquid into the gas phase, without nucleating a bubble.

You beat me to it! I was just about to update my post with facts about "isostatic pressure" and "nucleation point".

Really though, thanks for the info.

 

[Putterrr]

Bubble formation is greatly aided if there is a "nucleation point," that is, some asperity where the nascent bubble can get started.

As was mentioned earlier, putting a brush in your wine will give your the nucleation point. Substitute a 3 inch galvanized nail and you will have the same thing and its much easier to clean. With a white wine, you can see the bubbles forming around the nail and streaming to the top. I'm still experimenting with the nail but so far the results are impressive.

cheers

 

[sour_grapes]

I've been trying to think of a way to use glass with sharp edges, i.e., broken glass. I wanted to use glass to be sure it would be inert and impart no flavors. However, I cannot think of a reliable way to do this! A few weeks ago, we had people freaking out at the thought of drinking wine from a cracked carboy; imagine if we started using glass chips as degassing aids!

I don't know why, but the thought of putting a bottle brush in there bothers me. Your idea is interesting. Do you get any flavors from the zinc? (pH of wine is pretty acidic.) Hmmm, maybe something made out of stainless steel wire.....

 

[vacuumpumpman]

I have used marbles before and got good results

But I must say that the splash racking cane seems to do the best so far and easiest also

Thanks Steve

 

[BernardSmith]

I've been trying to think of a way to use glass with sharp edges, i.e., broken glass. I wanted to use glass to be sure it would be inert and impart no flavors. However, I cannot think of a reliable way to do this! A few weeks ago, we had people freaking out at the thought of drinking wine from a cracked carboy; imagine if we started using glass chips as degassing aids!

I don't know why, but the thought of putting a bottle brush in there bothers me. Your idea is interesting. Do you get any flavors from the zinc? (pH of wine is pretty acidic.) Hmmm, maybe something made out of stainless steel wire.....

I sometimes add a sanitized chopstick to help with nucleation

 

[sour_grapes]

I sometimes add a sanitized chopstick to help with nucleation

Hmmm, that is not a bad idea! After all, we put oak cubes in there!

 

[Putterrr]

I don't know why, but the thought of putting a bottle brush in there bothers me. Your idea is interesting. Do you get any flavors from the zinc? (pH of wine is pretty acidic.) Hmmm, maybe something made out of stainless steel wire.....

Not that I can tell. It's only in the carboy for 10 minutes. Nails are cheap. You could change it each time and use the old nail to hold up wine racks

cheers

 

[buckhorn]

I've been trying to think of a way to use glass with sharp edges, i.e., broken glass. I wanted to use glass to be sure it would be inert and impart no flavors. However, I cannot think of a reliable way to do this! A few weeks ago, we had people freaking out at the thought of drinking wine from a cracked carboy; imagine if we started using glass chips as degassing aids!

Would it have to be broken glass? I work in stained glass and you can get glass rods for doing hot work (ie. glass beads, etc....) Could you use something like that - it would be similar to using a glass swizzle stick in the carboy ?

Just thinking....

 

[sour_grapes]

Believe it or not, I don't actually understand the physics behind what causes bubbles to nucleate at asperities. But that is certainly the observation, in fact, you can buy Champagne glasses that are laser-etched to produce a certain pattern of bubbles.

Okay, I just went googling, and one recurring school of thought is that bubbles nucleate where there are small pockets of gas trapped between, say, some cellulose fibers. CO2 diffuses into this air pocket, the pocket expands, and then the bubble breaks off. I can see why this might work. The presence of the pre-existing air pocket overcomes the nucleation barrier I alluded to above. There is no need to nucleate a new bubble -- the existing one gives rise to a new one, repeatedly.

Soooo, maybe asperities are not what is required. Perhaps the important thing is air pockets. Makes the chopstick idea sound promising!

 

[vacuumpumpman]

I found the thread that Grasshopper came up with originally

http://www.winemakingtalk.com/forum/f6/falling-film-degassing-36757/

 

[richmke]

I would be careful about introducing something for nucleation sites. The same sites that seed gas bubbles are the same sites that are hard to sterilize (think scratch on the inside of the carboy).