Degassing via vacuum

[Harry Bloomfield]

I'm still waiting for my first batch of white wine to complete its fermentation. Started seven days ago today and I have been looking at methods to degas. Generating a vacuum in the FV seems the most effective method to my mind, so I'm looking at possible ways to create a vacuum.

General opinion seems to be that a vacuum cleaner's level of suction is not enough to be effective. In my garage I have one of those cheap as chips, 12v tyre inflaters/compressors, which as sat there unused for years because I have a big mains compressor. Where there is compression, there is suction and these things are capable of 125PSI - so if the intake can be tamed, it should produce much more than needed.....

This explains how such a cheap compressor can be modified, to make a intake / vacuum port.

 

[Chippy_Tea]

A nice set up but my method costs nothing (if you already have a drill) and its finished in a minute - https://www.thehomebrewforum.co.uk/threads/how-to-degas-wine-with-a-home-made-degassing-wand.48971/

.

 

[kelper]

Don't! It would not take much vacuum to collapse your FV.

 

[Harry Bloomfield]

Yes I saw that idea, but I fancied vacuum should be even more effective - besides I like faffing about with things...

I have just opened up my little compressor and its quite similar to the one in the youtube video, except it has two output ports - one for the tyre pipe and a second one for a pressure gauge. Rather than struggle to fit that too big brass nipple to make an inlet port, I used a 2" length of copper brake pipe, which I abraded to get good adhesion with some Araldite. Even the brake pipe was a little too wide to fit, so I had to squeeze it a little to get it flat down onto the cylinder head. I have now wait 24 hours for the Araldite to set up, before I can put it back together to test it.

 

[Harry Bloomfield]

I wasn't thinking of using quite that much vacuum :-)

 

[Chippy_Tea]

I wasn't thinking of using quite that much vacuum :-)

While the video is taking it to extremes there is a danger a vacuum could cause thin walled DJ's to implode, i noticed when i bought a new one a while ago how much lighter they are compared to my old ones so they must be a lot thinner, be careful out there!

 

[johncrobinson]

Chippy your dead right.Putting a vaccum pump on a demijohn is dangerous.Even if the demijohn could take it the wine would foam over. Sorry its not a good idea.

 

[Harry Bloomfield]

Chippy your dead right.Putting a vaccum pump on a demijohn is dangerous.Even if the demijohn could take it the wine would foam over. Sorry its not a good idea.

You do it in stages, using just a little vacuum in each stage to prevent there being too much foaming. The last thing you want is a mass of foam in the pump.

 

[johncrobinson]

I just use a cordless drill (So there is no mains voltage involved) The wand i use is just plastic so am keeping my eye open for a nice stainless one.

RE:> Harry sorry i dont think its a good idea not in a demijohn anyway.Demijohns these days are like eggs you arnt even supposed to put hot water in them.

 

[dwhite60]

You can buy a hand operated vacuum pump off ebay.

I pump until it starts bubbling, then wait for it to stop, then repeat. I'm cautious about how much vacuum I pull on a demijon. Kind of a cool process.

All the Best,
D. White

 

[johncrobinson]

The first time i ever really properly degassed a wine was a Solomon Grundy 7 day wine kit about 20 yrs ago.
The method stuck with me and i have degassed ever since.

 

[Chippy_Tea]

I remember shaking the DJ as instructed when I first started, I made a degassing wand soon after.

 

[Viamphie]

Being an ex refrigeration engineer I have a vacuum pump and gauges etc. A shraeder valve fits nicely into the air lock bung so I though I’d give it a go. I can confirm that the plastic 25lt FV collapsed inwards and the wine lost very little co2. Hmmm I won’t be using that method again. I’ve found that 5 or 6 transfers from one vessel to another at height is usually enough to degas.

 

[dwhite60]

Being an ex refrigeration engineer I have a vacuum pump and gauges etc. A shraeder valve fits nicely into the air lock bung so I though I’d give it a go. I can confirm that the plastic 25lt FV collapsed inwards and the wine lost very little co2. Hmmm I won’t be using that method again. I’ve found that 5 or 6 transfers from one vessel to another at height is usually enough to degas.

Always wondered how bad that would oxidize the wine? I'm sure it's effective though.

 

[Viamphie]

Can’t say I’ve noticed any difference in the taste compared to using a spoon. Then again I’ve only had the wine sitting in the bottles for a month but it still tasted ok

 

[Harry Bloomfield]

Being an ex refrigeration engineer I have a vacuum pump and gauges etc. A shraeder valve fits nicely into the air lock bung so I though I’d give it a go. I can confirm that the plastic 25lt FV collapsed inwards and the wine lost very little co2. Hmmm I won’t be using that method again. I’ve found that 5 or 6 transfers from one vessel to another at height is usually enough to degas.

I would have thought that pouring from a height would introduce a lot of air (oxygen)?

I try to minimise the introduction of oxygen when racking wine into bottles, but when a red has been opened ready for drinking, I decant it deliberately pouring from a height to introduce oxygen. That process does seem to improve the taste.