stabilizing fermented out wine

[Fran365]

As a new wine maker I thought of stabilizing as using Pot. sorbate and campden after all fermentation was over and before sweetening. I ran across a wine maker who said 24 hours in the deep freeze is an alternative to using these 2 additions. On my next batch of Welch's concord juice I tried that. After thawing the flavor was flat and weak. I've made 6 gallons or so of this wine and this batch was different. Additions of tannin and grape juice concentrate helped little. My question is: is freezing a way to stabilize a fermented out wine? Fran

 

[wildhair]

You are probably referring to cold stabilization, which is NOT freezing the wine, but holding the wine just slightly below 32 degrees for 2 weeks or so. The wine does not freeze at that temp because of the alcohol, but it kills the remaining live yeast. You can read about cold stabilization here -
http://winemaking.jackkeller.net/finishin.asp

 

[salcoco]

it will also cause any acid in the wine to fall out, therefore the flabby wine. cold stabilization should be reserved to remove acid not normally to stabilize wine,. once fermented out the fermentation will not restart as long as new food source is not supplied to the yeast.

 

[Fran365]

Thanks wildhair salcoco. First, I was not referring to cold stabilization. The wine was racked to a plastic jug and buried in a 0-F deep freeze for 2 days then thawed. One issue besides the points made is this particular wine had a PA of 10. Doing my wine work during this past winter gave me opportunities to cold stabalize, and in one instance the result was very nice. My poor records keep me from knowing exactly what I did. But the freezing idea is still in question. Fran
[ame]https://www.youtube.com/watch?v=oUSLlkhtefc&t=265s[/ame]
freezing @7:51

 

[stickman]

Freezing may help the wine settle out solids as well as tartrate crystals, but I wouldn't trust it as a substitute for potassium sorbate and/or campden. Yeast is routinely frozen and thawed and becomes active as soon as temperatures are back in range.

 

[wildhair]

I don't think I'd trust it as a replacement either & the Campden acts as a preservative in the bottled wine - cold stabilization doesn't do that. That said - if the sugars are fermented out, the lack of food + the alcohol level SHOULD keep the yeast from returning to life, no?

 

[bkisel]

Interesting and well done video, except for maybe the very end. The ending is an act is it not?

And I though I was frugal.

Did you guys check out the video noting the homemade equipment. Really like that siphon and how it is started.

 

[Fran365]

Thank you gents, I'm to old to look for absolutes in these type of questions, there is always a possibility for life to spring up.(Jurassic Park?) My interest in less additives sprang from my work in alternate medicine, where one hears," beer and wine are fine foods, but make them yourself". The implication is, as in all manufactured foods, that Corporations will add/ do anything to increase profits, often to the detriment of long term health. Fran

 

[wildhair]

The siphon starting was definitely a cool idea! I may try that one. The screw on airlock was also pretty ingenious.

The implication is, as in all manufactured foods, that Corporations will add/ do anything to increase profits, often to the detriment of long term health

Sometimes it's not about profits, but about protecting one's business from a lawsuit happy culture. They often over-protect food, including wine & beer, with the maximum amount of preservatives (i.e. - pot. meta.) for that reason. However - you don't want to open a bottle of wine and discover it's gone bad, either. IMO - A little preservatives is good insurance to protect all the efort that went into making the wine.

 

[jswordy]

I regularly use cold to precipitate out potassium bitartrate (wine diamonds) from wine made with grapes. It does have the side effect of killing the yeast. People generally don't like tartrates in their bottles when I give away wine, and some people will not drink wine from such a bottle even after I tell them there is no ill effect. It's so easy to fix the problem, so I do.

True, it can make wine flabby, but for me that's easily remedied on the back end with supplemental acid. I have medaled with wines made in this way. Your mileage may vary.

Yeast can also be killed by just subjecting them to high alcohol in the carboy over a long storage time. There are lots of techniques for high alcohol wines that do this, and for ways of lessening the alcohol on the back end prior to bottling the finished product.

In the past, up to in some cases the 1960s, some commercial wineries actually used to quickly heat the wine as it passed through a tube to kill off yeast. That practice declined as chemical stabilization methods took hold.

The key with wine that is not stabilized chemically is that the shelf life is shorter.

Freezing is usually reserved for concentrating the alcohol in wines, (grappa) in which case it is a form of distillation and is not allowed to be discussed here last I knew.

 

[Fran365]

Hi Wildhair, the gent in the YT I posted (CrypticCRICKET) is an interesting fellow, he also makes firearms in his garage , very interesting. Jswordy, thanks for the thoughtful response. I understand more about freezing. It has dawned on me that fall and winter vinting may take advantage of garages that run 20-30F. You mention supplemental acid post fermentation and post cold/freeze episode. I've only added acid blend before pitching, do you add it, say 1/4 tsp./gallon followed by taste test as when sweetening before bottling? Fran

 

[wildhair]

You mention supplemental acid post fermentation and post cold/freeze episode. I've only added acid blend before pitching, do you add it, say 1/4 tsp./gallon followed by taste test as when sweetening before bottling?

I know this Q was not directed at me, but I had some honeydew wine that tasted flat and flabby. Ph testing showed the ph over 4. I added both citric acid and acid blend post-ferment and had to add a considerable amount to get the ph down to the mid-3's. It was a 2 gal batch and I added 1/2 t at a time until it tasted better. Took about 4 -5 t by the time I was done.

 

[skeenatron]

Cold stabilizing your wine after all fermentation is complete is totally fine to do. It won't drop out all of your acid and make the wine flabby, it will just drop out unstable tartrate which won't have a major impact on overall acidity. Dropping the temperature down like that temporarily is by no means a safe way to keep your wine stable from a microbial standpoint however. Many, many strains of both yeasts and bacteria can survive those conditions, then resume ruining your wine once you warm it up again. Even if you do have all the glucose/fructose, and malic acid fermented out of your wine, there are a large number of five carbon sugars and acids that can be metabolized by your microbes, allowing them to continue to thrive.

Sulfur dioxide (Campden tablets) is your friend. At proper levels it will keep your spoilage microorganisms at bay, keep your wine from enzymatically browning and oxidizing, and it also binds to acetaldehyde which is important to the flavor. Keep it cold, keep it sulfured, and you're good to go.