sealing wine in bags

[Judith McCann]

Brand spankin’ new to wine making, but we have ten gallons fermenting. We realize that if, instead of bottling, we seal in vacuum bags the wine will not age. Other than that, are there any problems that we should be aware of? We have a vacuum chamber, so the sealing part will be no problem. Thanks so much for any thoughts. It’s great to find a place with so many experienced folks!

 

[TechFanMD]

I put my wine into bags specifically meant for the purpose - just like the bags from boxed wine but you can buy new ones in a variety of different sizes. Amazon and homebrew stores sell them.

Why wouldn't the wine age? You wouldn't want to age it in bags, but it will still mellow and improve with some time, depending on the type. I don't really understand that 'vacuum' part.....a bag can be squeezed until there is no air and sealed shut. If you pull a vacuum you'll start sucking liquid - same as just squeezing the bag. Maybe this is more a matter of how your vacuum sealer works.

 

[jgmillr1]

We realize that if, instead of bottling, we seal in vacuum bags the wine will not age. Other than that, are there any problems that we should be aware of?

The "aging" process refers to some combination of allowing the wine time to (1) settle particulates such as yeast, (2) absorb some oak flavors if exposed to oak, and (3) allow tannin polymerization in the case of "big reds". Aging is not a bad thing that should be avoided, but it should be managed for the style of wine you are making.


Most plastic or containers are permeable to oxygen, to varying degrees. Oxygen exposure will eventually lead to your wine spoiling and this is what must be avoided. I would be cautious about the bag you are intending to use. Glass bottles with good quality cooks will preserve your wine for a long, long time.

 

[bernardsmith]

Hi Judith McCann and welcome... This is a response to jgmillr1. I would have thought that a vacuum sealed bag - if properly sealed will not allow in any oxygen - certainly not in the short run (otherwise it should not be called "vacuum sealed") BUT micro-oxidation, as permitted by corks, IS something that is beneficial. That why storing wine in bottles is good and s one reason why storing wine in barrels is also considered good for wine - the wood also allows access of molecules of air to the wine.

 

[jgmillr1]

This is a response to jgmillr1. I would have thought that a vacuum sealed bag - if properly sealed will not allow in any oxygen - certainly not in the short run (otherwise it should not be called "vacuum sealed") BUT micro-oxidation, as permitted by corks, IS something that is beneficial.

My concern is with the oxygen permeability of the bag material itself and not purging or vacuum sealing the bag. Oxygen making its way past a cork with a surface area of <5cm^2 is much less impactful than the potential of going through an entire bag with a surface area of >400 cm^2. If the op obtained the same thick bags used in packaging boxed wines, then that would extend the life span of the wine. Regardless, a bagged wine isn't going to be one you'll set on a shelf for a long time.

It may not be an issue as most home winemakers work through their hooch at a regular clip. Hell, 15 years ago I used to just keg the wine so as to avoid the bottling labor!

Wines and Vines had an interesting article on oxygen transmission through different corks a few years ago that I'm not able to locate at the moment. It compared different cork types and tracked dissolved oxygen over years. I recall the bottom line was that screw caps were the best and synthetic the worst for oxygen transmission.

 

[gregbathurst]

Ordinary plastic bags will allow a lot of oxygen through, the wine will spoil quickly because the barrier is very thin, unlike plastic drums and buckets which are much thicker so allow less oxygen to permeate. The bags used for wine have a foil layer which makes them less permeable to oxygen.

 

[bernardsmith]

Ordinary plastic bags will allow a lot of oxygen through, the wine will spoil quickly because the barrier is very thin, unlike plastic drums and buckets which are much thicker so allow less oxygen to permeate. The bags used for wine have a foil layer which makes them less permeable to oxygen.

Ordinary bags - of course but the question was about bags that are vacuum sealable.. and if those were so very permeable then you would not be able to pull a vacuum. I make cheese and I sometimes age my cheese in vacuum sealed bags. Those bags appear to hold a vacuum for months...

 

[Judith McCann]

The "aging" process refers to some combination of allowing the wine time to (1) settle particulates such as yeast, (2) absorb some oak flavors if exposed to oak, and (3) allow tannin polymerization in the case of "big reds". Aging is not a bad thing that should be avoided, but it should be managed for the style of wine you are making.


Most plastic or containers are permeable to oxygen, to varying degrees. Oxygen exposure will eventually lead to your wine spoiling and this is what must be avoided. I would be cautious about the bag you are intending to use. Glass bottles with good quality cooks will preserve your wine for a long, long time.

These would be heavy vacuum bags. Do you think it would be different from the boxed wine one can buy in the store?

 

[Judith McCann]

Thank you all. This wine won’t be stored long. And the bags I buy are heavier than even typical vac bags. I think for our first time, we’ll bottle some and vac seal some. We’ll guinea pig it. Thanks again!

 

[gregbathurst]

Ordinary bags - of course but the question was about bags that are vacuum sealable.. and if those were so very permeable then you would not be able to pull a vacuum. I make cheese and I sometimes age my cheese in vacuum sealed bags. Those bags appear to hold a vacuum for months...

You have to be careful abut these assumptions. Air is only 20% oxygen, the rest is nitrogen, so you only have to keep out the N2 to give the impression of a good seal. The small airspace is already 20% O2 so there isn't any concentration gradient to draw in oxygen and the cheese won't be consuming much O2. Wine is different, it is constantly consuming O2 so there is a constant gradient drawing O2 into the bag. Even a heavier bag will allow a lot of O permeability. Do you really think they would bother with the foil layer if it was ok to just use a slightly thicker bag?