TCA

I also wonder what's in the wrap that comes out into the wine. Mark, what are they using for plasticizers these days?

Oswaldo, btw, TCA is quite snobbish and inert.
 
originally posted by MLipton:
Maximization of surface area occurs when you crumple up a big sheet of plastic wrap (I haven't done a study, but the original Jamie Goode post used LDPE, not PVC) and completely submerge it in the wine. If it's properly done, the removal of TCA should be complete within a minute or two, not days. The process can be sped up by stirring the wine within the container to move it over the plastic wrap. My own subjective analysis is that, though the TCA smell can be reduced or eliminated, the wine that's left is still damaged goods, less aromatic and fruity than an untainted sample.

Mark Lipton
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A NYT article by Howard McGee quotes Andrew Waterhouse of UC Davis: "Mr. Waterhouse said that the obnoxious, dank flavor of a “corked” wine, which usually renders it unusable even in cooking, can be removed by pouring the wine into a bowl with a sheet of plastic wrap.

“It’s kind of messy, but very effective in just a few minutes,” he said. The culprit molecule in infected corks, 2,4,6-trichloroanisole, is chemically similar to polyethylene and sticks to the plastic."
 
originally posted by kirk wallace:
originally posted by Oswaldo Costa:
Thanks, Nigel, that's helpful. Given that it's an Overnoy, I'm trying to reduce the TCA to a level where I can con myself into thinking that it doesn't prevent pleasure, an iffy quest at best.
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So, what is the best approach? Use an impeccably clean glass roasting pan lined with the polyethylene to maximize the surface area? And original Saran is PVC, whereas Glad cling and new Saran Premium are LPDE (low density polyethylene; is one better for TCA removal than the other? (I am taking Nigel as saying PVC, at least the ones he's tried, impart flavor to the wine.)
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Kirk, IIRC original Saran Wrap [US product] is no longer made and was PVDC, polyvinylidene chloride, rather than PVC or Polyvinyl Chloride which is what most UK cling film/wrap is made of.
We have to look hard here for a pure polythene formulation although rather more food and deep freeze bags are made of polythene which can also be used.

I am not sure about PVDC in the past but AFAIK PVC uses plasticisers to achieve the cling effect and it is these that can cause the problem with taste. Through changed formulations I believe the plasticisers in modern PVC are no longer the health hazard they once were but I still find they add a significant plastic taste to the wine.

I believe Saran Wrap both Premium and Cling Plus is polythene today and has been for many years.

If it is easy to find I would go for the Premium non-cling product and put a couple of lightly crumpled sheets in the largest glass jug you have and pour the wine in. I say ‘lightly crumpled’ since surface area is important and crumpling it should allow it to stand up in the jug so all the wine is in contact with some part of the polythene. A better solution might be solid table tennis size polythene balls such are used in some professional processes but they are not readily available.

Leave it for say half an hour and pour the wine slowly into another jug. Dispose of the used polythene and repeat. If the smell is still obvious do it again. If that hasn’t worked give up but I have found that one or sometimes two treatments has usually improved things particularly if the TCA has been very obvious from the start. However as I say it has never satisfactorily resolved the issue for me and I believe that is due to the residual TCA which cannot be completely removed by this method.

Obviously oxidation can become a significant issue if this process is undertaken over many hours or even days. However AFAIK the adsorption mechanism works immediately and time is only necessary to ensure that the TCA throughout the wine makes contact with the polythene surface say 30 minutes.

However for those who believe extended surface contact time is vital I have heard of the polythene being inserted as a roll into the bottle itself, a bung [e.g. a VacuVin stopper] inserted and put in the fridge for a day or two which should at least reduce the oxidation risk.

I am sure you are aware of those who impute the existence of TCA even when they cannot smell it, even after a long time in the glass, simply because the wine doesn’t seem to be delivering what they expect or have previously experienced. Personally I find it hard to accept that a product as powerful an odorant as TCA is the only explanation for less than perfect wine when alleged super-sensitives [some claim to be able to detect TCA at 1-2 ppt] never actually smell the stuff. After all there are reasons other than TCA that can cause a wine to be muted in taste. While the second bottle which tastes ‘correct’ is often used as proof that it was TCA [with the different corks allegedly the sole possible variable and therefore the definitive source of the contamination] there are other winemaking and bottling possibilities that suggest that the ‘second bottle’ proof is not infallible.

In any event most TCA, and certainly the bottle that is behind this thread, is usually evident to most who know and drink wine regularly although a surprising number of drinkers [as opposed to geeks] have never knowingly experienced it and that is not just a threshold issue. Experience is not unimportant in its identification and once that knowledge is gained the sad fact is that the experiences have tended to multiply.
 
I'm perfectly happy to think that I have only variable success because I am not doing it the best way. I'll be even happier to think that it will work in minutes, not days. But how often does it work this way? I used to bowl method once, and it seemed to have almost no effect.
 
originally posted by Jonathan Loesberg:
I'm perfectly happy to think that I have only variable success because I am not doing it the best way. I'll be even happier to think that it will work in minutes, not days. But how often does it work this way? I used to bowl method once, and it seemed to have almost no effect.
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Jonathan,
It has always worked for me in the sense that the TCA is greatly diminished in smell in a relatively short time - although I have occasionally run it twice. As I have said it doesn't work for me as a perfect cure because the wine remains degraded.

Why hasn't it worked for you? Here's a couple of possibilities:
Firstly you may be supersensitive to TCA and although it is being considerably reduced it is remaining well above your threshold so you not only still smell it but the wine hardly seems improved.

Secondly I am thrown by your reference to 'original' Saran Wrap since that was PVDC rather than polythene [polyethylene] although I think the product formulation was changed to polythene many years ago. If by some chance you are using PVDC it may not be as effective as the modern polythene formulation although I doubt that would explain your problem.

The only other possibility I can think of is whether you are providing the surface area and ensuring the wine is fully exposed to it. This is why I suggest the Premium product may be better suited than the Cling Wrap but that is pure surmise since I have no ides how you are using it.
 
Plastics will extract flavor components out of the wine as well. Many tasty smellies in wine are quite hydrophobic and will also partition into the film. So you can get the TCA out with this process, but not without removing other things and perhaps adding some.

I dump corked wine, myself.
 
originally posted by SFJoe:
I also wonder what's in the wrap that comes out into the wine. Mark, what are they using for plasticizers these days?
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LPDE is extruded as a film with no plasticizers needed. PVC and PVDC are anyone's bet.

Mark Lipton
 
originally posted by MLipton:
originally posted by SFJoe:
I also wonder what's in the wrap that comes out into the wine. Mark, what are they using for plasticizers these days?
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LPDE is extruded as a film with no plasticizers needed. PVC and PVDC are anyone's bet.

Mark Lipton
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This whole discussion makes me want to try it on a non-corked bottle and compare the result to another non-corked bottle of the same wine. (I won't be sacrificing any of my Overnoy for this experiment, however.)
 
I just want to know - is it OK to throw US pennies into my 09 schaefer, or do I need euro cents ?
 
originally posted by SFJoe:
Plastics will extract flavor components out of the wine as well. Many tasty smellies in wine are quite hydrophobic and will also partition into the film. So you can get the TCA out with this process, but not without removing other things and perhaps adding some.

I dump corked wine, myself.
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I do too but I mentioned earlier that I have tested polythene in ‘uncontaminated' wine and tasted glasses that had the polythene 'treatment' for 20-30 minutes versus glasses from the same bottle without polythene and found no significant difference.

While there may indeed be ‘attractive’ wine components that will be adsorbed onto a polythene surface have any been identified and, if so, what the extent of the adsorption [very significant for TCA] is?

Of course my experiment may simply be demonstrating that I have a rather insensitive palate but this is the first of these [many] discussions where I have seen that “many tasty smellies in wine are quite hydrophobic and will also partition into the film”. I understand the first part but have not seen such a definite statement re the second part. Lots of surmise about the possibilities but no specifics so any that are known would be appreciated.

There are professional wine services that use polymers in their TCA removal process so I wonder how they would deal with a significant ‘denaturing’ of the product if that is occurring to a significant extent. Of course these are unlikely to be fine wines but nevertheless one might have thought it unlikely that the impact would be significant - and if it was there would be some caveat in their terms of service.
 
originally posted by nigel groundwater:
have any been identified and, if so, what the extent of the adsorption [very significant for TCA] is?
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I would say that logP would give you a pretty good guess for any flavor component you examine. There is little sense in doing each experiment. What you're doing is a solvent extraction into a very viscous solvent. Surface effects (except for kinetics driven by area) are probably irrelevant.
 
I was just updating Marcia on the latest developments in this thread. When I got (very matter-of-factly) to the part where Nigel said he put untainted wine through plastic and found that it had no effect, she laughed and said "the great thing about this board is that has people even crazier than you."
 
originally posted by nigel groundwater:
originally posted by Tom Blach:
I opened no corked bottles at all for the first seven months of this year. Then I opened five in a row,all quite grand wines,annoyingly.
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Tom,should I assume these were all wines from an era when a 'corked' bottle was a more likely event than in more recent years? An indication of the 5 vintages would be much appreciated?
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96,98(2,the same wine)99,00.
 
originally posted by Tom Blach:
originally posted by nigel groundwater:
originally posted by Tom Blach:
I opened no corked bottles at all for the first seven months of this year. Then I opened five in a row,all quite grand wines,annoyingly.
Click to expand...
Tom,should I assume these were all wines from an era when a 'corked' bottle was a more likely event than in more recent years? An indication of the 5 vintages would be much appreciated?
Click to expand...

96,98(2,the same wine)99,00.
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Thanks Tom.

While it does nothing to alleviate the pain one might still expect an unacceptable proportion of corks affected by TCA in that date range since most of the major process [harvest, storage and production], facilities and testing improvements took place after those dates.
 
Anyone here tried using Half & Half to remove TCA from wine? It is supposed to be effective, but I am not sure how easy it is to separate from the wine afterwards in a domestic environment.
 
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