DIAM - yes please!

For many, the plural of anecdote is data...
Of course there are different qualities of data and 'anecdotal' is usually the least reliable since they are usually unaccompanied by any validation.

Nevertheless if there had been an enormous number of negative reports, anecdotal or otherwise, concerning DIAM there would be an added significance - as with the pox phenomenon and, more relevantly, with DIAM's failed predecessor, the ALTEC, which unlike DIAM did not live up to its promise to have eradicated TCA which could be confirmed using GC-MS testing.

AFAIK there have been no claims of TCA from a DIAM closure that have been substantiated by laboratory testing and in any case such claims have been very few in number and usually suspect for a number of reasons some of which have been suggested in this thread.
 
That is an interesting study Tony. It sounds as though it's impartial and reasonably well conducted, although the "brought into contact" in a flask isn't the same as being sealed in a bottle. He's comparing, if I understand, wines put in flasks where one has a DIAM cork floating in the flask, therefore much higher surface area in contact with the wine and notably the sides, which wouldn't normally touch the wine (DIAM uses ink on the sides).

However, he may be on to something. If I could point to something it would be ATB (which I call "being closed") rather than glue flavours.I think I may have to find my dual-sealed wine and try them tonight.
 
Whether it were on Haut-Brion, or Fourrier, I think I would always be pleased to see DIAM. I think we are at a turning point in acceptance ... just needs a few years experience for the consumers and producers with some really good wines bottled and aged under DIAM before we start to see top wines converting too.

Jonathan, your statement that "The length has absolutely no influence on the wine" seems oddly biased.
Cork is a natural material, with hidden defects. Sometimes the defects allow enough permeation of oxygen to ruin the wine.
Surely it is the case that a more apparently perfect cork (one with fewer visible surface defects) and a longer cork stand more chance of protecting the wine properly ?
Obviously they don't make the wine itself better, but they do make its chances of surviving the intended cellaring period better ...
 
Just to throw this into the mix a small and not very well explained study on Diam out of Germany.

By Rolf Cordes, it covers a problem he likes to call Atypical Bitterness (ATB).

Can't say I have experienced the symptoms of ATB personally in DIAM wines
Interesting but IMO strangely unconvincing although it would be surprising if this wasn't followed up by some professionals in closures and wine chemistry like Pascal Chatonnet, Scott Labs, ETS Labs et al. Presumably DIAM themselves would take an interest since they are already defending in the USA against allegations concerning a taste imparted by the glue.

However the interaction between [any] closure and the wine it closes is a key determinant in how the wine finally presents when opened so one might reasonably expect a wine closed by DIAM v natural cork v screwcap v Vinolok v twin top v Ardeaseal v synthetic to all present differently - although depending on the type of wine, winemaking, timing and excepting obvious flaws such as TCA such differences are likely to range from infinitesimal to obvious.

It seems clear that Cordes believes that the DIAM cork, rather like TCA from a natural cork, imparts a chemical or chemicals directly [and quickly] to the liquid [wine or water] that it comes in contact with which, while having a difficult to sense olfactory impact, has a more obvious ATB taste effect. He has then sought to validate his impressions based on personal experience by using 8 wines and one water sample on their own and, separately, in contact with DIAM [how: bobbing around in a flask or in the neck as per a wine bottle, if bobbing, one or more per flask? whole or in pieces?] over varying periods with the longest having only 94 days in contact with most at 3 days and less.
These samples have then been tasted by a group of wine professionals.

However as with the 'glue' allegations I would have though the most effective test would have been a differential chemical analysis using GC-MS to see what chemical/s was/were added [if any] to the samples through the use of DIAM by comparing the with and without samples - and a lot more than 8 with a far greater time range. Of course, if as Cordes seems to claim, ATB can be recognised from all DIAM corks after only a matter of hours then laboratory testing should be able to determine the source and nature fairly quickly just as it can with TCA and other cork-related olfactory and taste affecting compounds.
 
Whether it were on Haut-Brion, or Fourrier, I think I would always be pleased to see DIAM. I think we are at a turning point in acceptance ... just needs a few years experience for the consumers and producers with some really good wines bottled and aged under DIAM before we start to see top wines converting too.

Jonathan, your statement that "The length has absolutely no influence on the wine" seems oddly biased.
Cork is a natural material, with hidden defects. Sometimes the defects allow enough permeation of oxygen to ruin the wine.
Surely it is the case that a more apparently perfect cork (one with fewer visible surface defects) and a longer cork stand more chance of protecting the wine properly ?
Obviously they don't make the wine itself better, but they do make its chances of surviving the intended cellaring period better ...
+1
And then e.g. Fourrier, having sourced his special natural corks from Corsica [IIRC] then adds a wax coating to provide an extra barrier over the critical glass/cork interface in the neck where various studies have shown it to be the most likely oxtrans route in the event of defects whether from the closure itself or the manner of its insertion or the size of the bottle neck.
 
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When I've spoken to cork suppliers, they have all said that the length is aesthetic. The oxygen entering the wine is almost all from inside the cork, unless the cork is faulty. So a long cork has a bit more oxygen to give to the wine but it doesn't reduce oxidation of the wine. Long corks tend to be made only from the best category of cork anyway.
 
Thanks for the clarification Jonathan; I wonder what proportion of corks prove to be faulty over say 20 years ?

Probably miniscule, but even so I guess if I were spending big money on wines, I would want to be reassured that the producers were not skimping on corks, so big and beautiful it would need to be (unless one is convinced on DIAM).
 
Interesting but IMO strangely unconvincing although it would be surprising if this wasn't followed up by some professionals in closures and wine chemistry like Pascal Chatonnet, Scott Labs, ETS Labs et al. Presumably DIAM themselves would take an interest since they are already defending in the USA against allegations concerning a taste imparted by the glue.

However the interaction between [any] closure and the wine it closes is a key determinant in how the wine finally presents when opened so one might reasonably expect a wine closed by DIAM v natural cork v screwcap v Vinolok v twin top v Ardeaseal v synthetic to all present differently - although depending on the type of wine, winemaking, timing and excepting obvious flaws such as TCA such differences are likely to range from infinitesimal to obvious.

It seems clear that Cordes believes that the DIAM cork, rather like TCA from a natural cork, imparts a chemical or chemicals directly [and quickly] to the liquid [wine or water] that it comes in contact with which, while having a difficult to sense olfactory impact, has a more obvious ATB taste effect. He has then sought to validate his impressions based on personal experience by using 8 wines and one water sample on their own and, separately, in contact with DIAM [how: bobbing around in a flask or in the neck as per a wine bottle, if bobbing, one or more per flask? whole or in pieces?] over varying periods with the longest having only 94 days in contact with most at 3 days and less.
These samples have then been tasted by a group of wine professionals.

However as with the 'glue' allegations I would have though the most effective test would have been a differential chemical analysis using GC-MS to see what chemical/s was/were added [if any] to the samples through the use of DIAM by comparing the with and without samples - and a lot more than 8 with a far greater time range. Of course, if as Cordes seems to claim, ATB can be recognised from all DIAM corks after only a matter of hours then laboratory testing should be able to determine the source and nature fairly quickly just as it can with TCA and other cork-related olfactory and taste affecting compounds.

My thoughts exactly Nigel. HPLC would also be important if the so called ATB causing compounds are non-volatile.

Last night I opened a 2007 Sandihurst Nelson Riesling from in NZ sealed under DIAM. Certainly didn't find any 'bitterness' per se, although it was a little astringent to begin with and quite closed given its age. With a bit a air it softened up nicely. I'm pretty happy as I picked up a case of this wine for silly money and it stills has loads of life in it, and I can rest in the knowledge of none of these being corked.
 
Thanks for the clarification Jonathan; I wonder what proportion of corks prove to be faulty over say 20 years ?

Probably miniscule, but even so I guess if I were spending big money on wines, I would want to be reassured that the producers were not skimping on corks, so big and beautiful it would need to be (unless one is convinced on DIAM).

And this concept will be perpetuated. Cork salesmen come to me all the time with the pitch that top burgundy producers buy their 3,50€ corks and I should too if I respect my wine.
 
The boss of DIAM (or someone near the very top) is quoted as saying that "as a supplier to nearly 50% of white Burgundy’s grand cru producers, many leading Champagne makers and several other well-known wine producers across France, “if our corks made the wines bitter we would (k)now about it.”" I have no idea if that is an accurate figure. The Champagne bit I can believe, but are 50% of Grand Cru white Burgs really sealed (these days) under DIAM? If so, that's a quite remarkable statistic, especially as I have been predicting for so long that DIAM is the future of wine bottle closures. ;)
 
Leon

You need to read carefully what the DIAM guy said. It was typical PR-speak.

Just because a GC producer is supplied by DIAM doesn't mean that the producer uses them on all his GC wine, or any at all. Maybe they are only used on lower ranking wines, or they are doing trials. And even if 50% of producers do use them on ALL their GC wines, it does not necessarily imply that 50% of all GC wine is under DIAM.
 
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Duncan,
Hence my first line re non scientific.
Also, we do drink mainly champagne and white wines and many of the top producers have not gone down the Diam route, at least for the top wines, so that may skew my experience.
I can understand that many in the wine trade would support something that cuts down on wastage..... but then I am only in the drinking business.

Resurrection... Its easy to get hung up on oxygen and oxidation in Champagne (particularly around the shock of disgorgement), but I think Ray is on to something. Perhaps DIAM along with a quick disgorgement (and SO2 in the liqueur) is a recipe for banality. I'm no fan of Oxidative Champagnes, but most aromas stem from some sort of interaction with oxygen (at some point, and DIAM will no doubt reduce oxygen ingress). Perhaps for Champagne DIAM is like Jetting, the process encourages "very little or no oxygen exposure" and probably a bad thing, surely a metered dose of the old O2 is required at disgorgement for both.
 
I did a subjective DIAM versus cork test last weekend. I bottled my 2010 Tahi and 2014 Three Peaks under both DIAM 5 and a decent quality Travet natural cork.

I opened all 4 bottles at the same time and tasted them with two different groups of visitors. Here are my thoughts.

On first opening, I found the wines sealed with Travet more open, rich and fragrant than the DIAMs, which were both a bit more closed. However, the other tasters were split down the middle on which they preferred.

A day later, the Tahi under cork was still showing more pretty evolution than the DIAM one, which had more depth and concentration. The Three Peaks was more difficult to judge. I found the DIAM one fruitier on nose and palate.

I'd always felt that the bigger, more tannic wines that require time would develop better under cork and the less tannic wines would not be so affected. I think these beliefs were generally supported by the trial.
 
My current fault rate with cork is about 1 in 50, possibly more, and the two wines I can think of this year were both lower end and both replaced by the sane merchant.

I don't believe cork is the issue with premox in Burgundy.

Is anyone else having much higher failure rates?

Edit: I might just leave that prophetic cum oxymoronic typo. :)
 
I've only been using DIAM for a few years now, but I'm thus far very happy with the results.

The TCA taint rate (as observed by winelovers sensitive to it) has been 0% on the over 200 bottles that I know the results of being opened in that time.

I had heard of the glue-taint theory, but I've never experienced it myself. I may have to undertake some experimentation...
 
The reason many say it's not just winemaking is that pox hits variably within the same case of the same wine. If looking for intra-case variability, where storage etc. have been identical, then cork really is the most obvious answer. I wish I could place my hands on the wonderful picture of Hunter semillons - all the same wine / same vintage in the same case, with colours running the full range from pale to f*cked loved up.

That said, if the corks alone were the problem, all cork sealed wines would be getting hammered by premox.

Thus it seems highly likely that certain winemaking decisions, when given the variable effectiveness of cork seal, gives variable levels of POx.
 
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