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Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Tue Jul 22, 2008 2:39 pm
by Oswaldo Costa
Michael Pronay wrote:With corks, a vacuum seems to be the standard procedure also over here — while with screw-tops, it's definitely not.


There's no reason why they should be any different, is there?

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Tue Jul 22, 2008 3:09 pm
by Oliver McCrum
Michael Pronay wrote:Oliver

are we talking about cork or screw-caps? With corks, a vacuum seems to be the standard procedure also over here — while with screw-tops, it's definitely not.


I was referring to cork, because sadly the Italian wine business is very behind in this regard, and the discussions I've had with producers are to do with corks. Sparging when applying screwcaps appears to be normal here, and given the obvious risk of leaving a great big slug of air on contact with the wine, I can't imagine why anyone wouldn't do it. (Apparently the problem with corks is that if you don't get rid of that air somehow, the insertion of the cork acts like a bicycle pump, adding a jolt of absorbed oxygen. The absorbtion would be slower in the case of screwcaps, as there's no pumping action, but there's much more air. If I understand the process of bottling correctly, one of the main goals is to avoid absorbed oxygen.)

So you've asked a bunch of producers and they firmly state that they do not sparge?

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Wed Jul 23, 2008 1:12 am
by Michael Pronay
Oswaldo Costa wrote:
Michael Pronay wrote:With corks, a vacuum seems to be the standard procedure also over here — while with screw-tops, it's definitely not.

There's no reason why they should be any different, is there?

Of course there is a reason: The cork is inserted into the bottle neck which creates a pressure that might result in wine seeking its way out between cork and glass when the bottle is laid down immediately after the cork being inserted (something I have seen at the bottling line of Château Figeac some years ago).

With a screw cap, however, nothing is inserted into the bottle neck, so no need the create a vacuum.

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Wed Jul 23, 2008 2:27 am
by Oliver McCrum
My first Italian producer to use screwcaps, Thurnhof in the Alto Adige (or South Tyrol, from an Austrian perspective), just confirmed that he sparged with nitrogen.

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Wed Jul 23, 2008 3:14 am
by Michael Pronay
Oliver,

I just called Hannes Hirsch (Kamptal), and I have no problem to admit that I stand corrected: he — and all the collegues he knows of — do sparge, either with CO2 or nitrogen.

My wisdom came from Erich Polz (Weingut Erich & Walter Polz, Südsteiermark) who told me that they wouldn't sparge at all, and I made the mistake to generalize ... :oops:

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Wed Jul 23, 2008 6:21 am
by Victorwine
Wouldn’t gas molecules move from areas of “high” concentration to “low” concentration? As far as gasses getting dissolved in the wine from the headspace wouldn’t it just reach a certain “saturation” point? Modern day bottling lines are designed to minimize the amount of O2 “pick-up”.

Salute

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Wed Jul 23, 2008 6:44 am
by Oswaldo Costa
And here I was, thinking that the vaccum/inert gas had a very different purpose, one that would apply equally to both corks and screwcaps: that of preserving the wine by delaying the oxidative effects caused by the bubble of oxygen between the liquid and the seal...

Well, then the issue between cork & screwcap seems to have become even more complicated: under cork with sparging, we all seem to agree that there is gradual seepage that replaces the sparging with oxygen over time. One practical consequence of this is that a half bottle, under sparged cork, should age at the same speed as a full bottle, under sparged cork, during the first few years, only beginning to age faster as seepage makes the fill become more and more oxygen. Under screwcaps without sparging, we all seem to hope that there will only be as much seepage as the liner design allows. But the fill is 100% oxygen right from the start, making a half bottle begin to oxidise/age faster than a full bottle right from the get go.

If we want screwcaps to simulate the aging effects of a sparged bottle with an ideal cork, we would have to sparge screwcaps (just to avoid that initial oxidation) and then let the liner slowly exchange the sparging for air at the same rate as it would with an ideal cork. The screwcapped bottle would have to be a little smaller so that the bubble is the same size as it would be with cork.

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Wed Jul 23, 2008 12:07 pm
by Mark Lipton
Howie Hart wrote:Gasses which are not soluble are not recommended due to the risk of elevated bottle pressures.
[...]
Argon Ar OK


I have to wonder whatgases they exclude for lack of solubility: noble gases like argon are among the least soluble, yet argon is OK.

p.s. I've encountered a wine sealed with a Zork and I don't particularly like them.

Mark Lipton

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Wed Jul 23, 2008 12:14 pm
by David M. Bueker
Mark Lipton wrote:
p.s. I've encountered a wine sealed with a Zork and I don't particularly like them.



Don't blame the closure, blame the grue. :twisted:

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Wed Jul 23, 2008 1:30 pm
by Mark Lipton
David M. Bueker wrote:
Mark Lipton wrote:
p.s. I've encountered a wine sealed with a Zork and I don't particularly like them.



Don't blame the closure, blame the grue. :twisted:


I ate it. :P

Mark Lipton

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Wed Jul 23, 2008 1:41 pm
by Steve Slatcher
Victorwine wrote:Wouldn’t gas molecules move from areas of “high” concentration to “low” concentration?

Yes, but I'm not really sure where you are going with that one.
Victorwine wrote:As far as gasses getting dissolved in the wine from the headspace wouldn’t it just reach a certain “saturation” point?

If it were just a case of oxygen being dissolved, yes. But after oxygen goes into solution, it will react and thus be removed from the solution again allowing more to be dissolved.

But I remain to be convinced that the air in the ullage makes the slightest bit of practical difference compared with a) all the other air contact the wine will have had and b) the SO2 that will have been added to soak up oxygen before it damages the wine. I suppose for very careful winemaking and low S02 additions it might be important.

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Wed Jul 23, 2008 11:42 pm
by Victorwine
Oxygen quickly dissolves in the wine and because of things like temperature and pressure this could occur very quickly. But once the saturation point is reached no more (or very little anyway) oxygen will dissolve into the wine. As far as dissolved O2 reacting with SO2 and other components in the wine this takes a fairly long time. Besides not all chemical reactions involving O2 are all “bad
Heck when I find a barrel bung on the floor of my wine cellar after a day or two I don’t go into “panic” mode. For I know because of the “saturation effect” only a certain amount of O2 will dissolve into the wine. For that day or two the wine will remain saturated or nearly saturated. Once I re-bung it hopefully my SO2 will “scavenge” up the dissolved O2 and no ill effects of oxidation will take place.
As far as gas molecules moving from areas of “high” concentration to “low”, how does one maintain the “protective” blanket in the headspace?

Salute

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Thu Jul 24, 2008 2:00 am
by Steve Slatcher
Victorwine wrote:Oxygen quickly dissolves in the wine and because of things like temperature and pressure this could occur very quickly. But once the saturation point is reached no more (or very little anyway) oxygen will dissolve into the wine. As far as dissolved O2 reacting with SO2 and other components in the wine this takes a fairly long time. Besides not all chemical reactions involving O2 are all “bad
Heck when I find a barrel bung on the floor of my wine cellar after a day or two I don’t go into “panic” mode. For I know because of the “saturation effect” only a certain amount of O2 will dissolve into the wine. For that day or two the wine will remain saturated or nearly saturated. Once I re-bung it hopefully my SO2 will “scavenge” up the dissolved O2 and no ill effects of oxidation will take place.

Quite. That was my understanding. I hope it didn't seem like I was contradicting.
Victorwine wrote:As far as gas molecules moving from areas of “high” concentration to “low”, how does one maintain the “protective” blanket in the headspace?

Er, by having an oxygen-tight stopper. But if the bottle is on its side, the blanket will not protect as the oxygen will bypass it going straight from the environment, through the stopper to the wine. You'll need the tight stopper regardless. Still not sure whether your question was real or rhetorical point, though.

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Thu Jul 24, 2008 9:21 pm
by Bob Hower
Last night we had a group of friends over for dinner and general rowdiness. The theme was Greece (though admittedly a pretty loose interpretation) for reasons I won't go into. In keeping with that theme, one of the first to arrive appeared with a bottle of Greek red wine (I did not note the label.) It was corked. Had this not been immediately noted and pointed out, this person was prepared to just dismiss this bottle as simply a wine she didn't like, made by Greeks who probably don't know how to make good wine anyway, even though underneath the musty basement flavor was some pretty good tasting fruit and balance. How many bottles of corked wine, do you suppose, are consumed by people who don't know any better and just accept it as a wine they don't like and won't buy again? Lots, I bet. Oliver is right. This is so stupid. Does anyone know of a recent response by the cork industry to this? Or is the "cork industry" just a bunch of individual producers who may or may not be paying attention? Are there any wine store owners out there who could cite roughly how many bottles they see returned due to TCA contamination?

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Thu Jul 24, 2008 11:33 pm
by Oliver McCrum
Bob Hower wrote:How many bottles of corked wine, do you suppose, are consumed by people who don't know any better and just accept it as a wine they don't like and won't buy again? Lots, I bet. Oliver is right. This is so stupid. Does anyone know of a recent response by the cork industry to this? Or is the "cork industry" just a bunch of individual producers who may or may not be paying attention? Are there any wine store owners out there who could cite roughly how many bottles they see returned due to TCA contamination?


Absolutely. As an importer/distributor my experience is that very little corked wine is sent back. My sense is that most drinkers know that the wine isn't very good, they wouldn't buy it again, but almost none of them know what the word 'corked' means, so they don't know that they can return it.

I would add that most of the wine I do get back as 'corked' isn't corked at all.

If even 2-3% of all wine sold was returned this discussion wouldn't be occurring, let alone 5-10%.

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Fri Jul 25, 2008 3:06 am
by Steve Slatcher
Bob Hower wrote:Does anyone know of a recent response by the cork industry to this? Or is the "cork industry" just a bunch of individual producers who may or may not be paying attention?

Don't know what you mean by recent, but there has been a response from the big players in the industry over the past few years, and expensive corks should now be a lot less likely to be infected. It'll take a while for this effect to filter through though, and for us to discover how well they are doing. And it's not going to stop me seeking out screwcapped bottles.

Here is a recent article from a visit to a large producer: http://www.wine-pages.com/features/amorim-cork.htm

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Fri Jul 25, 2008 6:44 am
by Oswaldo Costa
Steve Slatcher wrote:Here is a recent article from a visit to a large producer: http://www.wine-pages.com/features/amorim-cork.htm


Thanks for the link. The sentence I found startling was "bottles sealed with cork do transmit oxygen to wine, but there is no ingress of external oxygen: 90% of cork's structure is air, so cork itself is responsible for transmission to the wine."

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Fri Jul 25, 2008 7:15 am
by Bob Hower
Thanks Steve. A fascinating and very encouraging article.

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Fri Jul 25, 2008 2:41 pm
by Mark Lipton
Oswaldo Costa wrote:
Steve Slatcher wrote:Here is a recent article from a visit to a large producer: http://www.wine-pages.com/features/amorim-cork.htm


Thanks for the link. The sentence I found startling was "bottles sealed with cork do transmit oxygen to wine, but there is no ingress of external oxygen: 90% of cork's structure is air, so cork itself is responsible for transmission to the wine."


Stuff and nonsense, Oswaldo. First of all, if the oxygen that enters a wine comes entirely from within the cork, you'd get a vacuum inside the cork and it'd collapse on itself. Since that (obviously) doesn't happen, oxygen must enter from the outside to replace that gas lost from within the cork. That's oxygen ingress. Moreover, I've heard it claimed that most of the oxygen ingress occurs around, not through, the cork, as the seal weakens with time.

Mark Lipton

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Fri Jul 25, 2008 4:47 pm
by Dave Guimond
Robin Garr wrote:Screwcap protects freshness?

What in the heck is a reputable retailer doing leaving a wine meant for early consumption on the shelf for all that time? The bottle was so shiny that they must have dusted the darn thing from time to time to keep it looking new. Adding insult to injury, they had raised the price 50 cents, too, although at least that's a lot lower rate of inflation than gasoline.



Hi Robin,

I haven't ready every comment in this thread, but I did not see your above comment addressed. Having worked in wine retail and wholesale, it is likely that the bottle you bought recently was not from the same case as the bottle you bought two years ago. Generally, distributors will buy dozens of cases of any given wine and store them in temperature controlled warehouses until all bottles are sold. The retailer will order more when their supply gets low. As for the price difference, distributors often fluctuate their asking price in order to spur sales, so the first case may have come in at a discounted price, which the retailer passed on to the consumer.

Hope to see you August 16th!

Dave Guimond

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Fri Jul 25, 2008 7:37 pm
by Oliver McCrum
Mark Lipton wrote:
Oswaldo Costa wrote:
Steve Slatcher wrote:Here is a recent article from a visit to a large producer: http://www.wine-pages.com/features/amorim-cork.htm


Thanks for the link. The sentence I found startling was "bottles sealed with cork do transmit oxygen to wine, but there is no ingress of external oxygen: 90% of cork's structure is air, so cork itself is responsible for transmission to the wine."


Stuff and nonsense, Oswaldo. First of all, if the oxygen that enters a wine comes entirely from within the cork, you'd get a vacuum inside the cork and it'd collapse on itself. Since that (obviously) doesn't happen, oxygen must enter from the outside to replace that gas lost from within the cork. That's oxygen ingress. Moreover, I've heard it claimed that most of the oxygen ingress occurs around, not through, the cork, as the seal weakens with time.

Mark Lipton


Yes, and it doesn't inspire confidence in their position if they are advancing such bogus arguments.

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Fri Jul 25, 2008 7:38 pm
by Oliver McCrum
Steve Slatcher wrote:
Bob Hower wrote:Does anyone know of a recent response by the cork industry to this? Or is the "cork industry" just a bunch of individual producers who may or may not be paying attention?

Don't know what you mean by recent, but there has been a response from the big players in the industry over the past few years, and expensive corks should now be a lot less likely to be infected. It'll take a while for this effect to filter through though, and for us to discover how well they are doing. And it's not going to stop me seeking out screwcapped bottles.

Here is a recent article from a visit to a large producer: http://www.wine-pages.com/features/amorim-cork.htm


Why would expensive cork be 'a lot less likely to be infected'?

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Fri Jul 25, 2008 8:30 pm
by Robin Garr
Oliver McCrum wrote:Why would expensive cork be 'a lot less likely to be infected'?

There are about a dozen legitimate reasons why it would be LESS likely, some of the biggies being the careful prevention of ground contact from the forest to the factory.

Cork-industry claims that TCA can be eliminated from natural cork may be dubious. But there's no question that a variety of quality-control approaches can reduce its incidence dramatically - at a cost for cork that many producers are unwilling to pay.

Re: WTN /Wine Advisor: Screwcap protects freshness?

PostPosted: Sat Jul 26, 2008 12:27 am
by Oliver McCrum
Robin Garr wrote:
Oliver McCrum wrote:Why would expensive cork be 'a lot less likely to be infected'?

There are about a dozen legitimate reasons why it would be LESS likely, some of the biggies being the careful prevention of ground contact from the forest to the factory.

Cork-industry claims that TCA can be eliminated from natural cork may be dubious. But there's no question that a variety of quality-control approaches can reduce its incidence dramatically - at a cost for cork that many producers are unwilling to pay.


With respect, Robin, I think that this is misleading. You appear to be suggesting that cork taint would be substantially reduced if producers were prepared to pay more; I know this isn't the case for my producers, and I suspect it isn't true generally. The blame for this problem can't be shifted to the customers, it remains squarely with the producers.

My understanding is that paying more guarantees one improvement only: appearance. It does not guarantee more QC, more freedom from taint. In fact I think Schildknecht made the argument that the most expensive, beautiful corks of all, those used by the best German producers for their best wines, suffered from higher than average incidence of TCA because of the way they were handled. I know a Sonoma Coast producer who pays a fortune for corks. His suppliers agreed to let him have his lab do QC on a sample from each bag of corks, and to let him return the ones that tested 5% or higher; he returns more than half of the bags.

The cork industry has been trumpeting certain improvements (such as avoiding the 'foot' of the bark, and avoiding contact with the ground or preservative-treated pallets) for ages, I don't think they are claiming that these improvements are only to be had with the most expensive corks.