Not, so far as we know, a cause of Lymes disease, but a closure made by Diam (or whoever is the company behind the Diam brand) specifically for sparkling wine.

By coincidence I have had a few corked Champagnes this past twelve months, which is not only a shame but an expensive shame for all of us who have shelled out lots of money only for our vintage wine to be buggered.

I've been reading a bit about ageing, especially after my recent visit to Bérêche, where all but the NV Brut Réserve gets aged under cork, not crown cap. So I know all sorts of things about oxygen exchange I didn't know before.

But I really know all too little about Mytik, except what Diam claim for it.

Should there be issues to think about and discuss? Whilst we ponder, I am off to bed (didn't sleep well last night), but I shall see whether Peter Liem has any observations.

Maybe Ray T, Po, Dr P, Mr P or others might know something?
According to the DIAM website, diam cork, similar to natural cork, has oxygen permeability, and producer can actually choose what permeability they prefer.
I can't find the actual data how they measure the permeability though. But from some report it looks like DIAM cork allows wine ageing as usual at least in the past ten years:
Jefford on Monday: The Diam corks debate - Decanter
If what they claim is true, then I don't see the ageing model, including CO2 escape process, will be hugely different. Just the cork will be intact better, and the texture in similar quality, therefore less variable.

The only issue I can think of is that the ageing of DIAM cork itself over ten years is not yet proven. It might be better than natural cork or worse.
I am also interested to know why DP and Roederer are against DIAM cork, especially thinking of some quite variable DP vintage (I can't imagine a vintage wine would be variable itself: the same wine in the same bottle, totally same cork and same storage condition should age the same. It can only be certain vintage more fragile to mainly cork variations, or simply corks used in that year was more variable)

For small scale buyers like me (I really buy comparatively small amount), I really welcome the concept of zero corked bottle and zero badly oxidised bottle. For the question if the wine would age well or not 15 years later.... I don't really know where I will be then!
Last edited:
I can't speak for the science but I don't mind as much as some the sensory experience of opening a synthetic closure (and is certainly nicer than screwcap / crowncap) especially if less chance of spoilage.

It's certainly better than the plastic closure i was surprised to find on a cremant de Bourgogne recently.

I have noticed Moet seem to be putting it on all their "normal" vintage releases now too?
Hi All, We love Diam @ Nyetimber. We've been using them exclusively since 2008 (we were disgorging 2003 vintage at the time), and in the 9.5 years since the switch I've not tasted a single TCA-affected bottle of ours, which is amazing. There's no way to ever know precisely, but we could consider that thousands of bottles have been spared from spoilage.

However, our main driver for the switch wasn't a TCA problem, but rather the variability that conventional corks bring to sparkling wines. In good examples, corks can bring lovely flavours to a wine (vanilla, toast etc), but not always. From one bottle to the next the cork can be having an entirely different influence, even setting aside the risk of TCA and differences in oxygen permeability. It's relatively unknown, even among winemakers, how much a sparkling wine can be marked by a cork in terms of flavour, without being faulted. In that regard we love Diam for it's reliability and neutrality... For better or worse, Diam always gives you a clear view of the wine, without interference. However I do think there are a lot of producers out there that like those positive cork flavours, maybe even counting on them for wine style, and therefore accept the variability as a necessary consequence. (or maybe they've never done the trials to notice how much of their end wine-style is determined by the closure...)
There's definitely been some discussion about wines not developing in the same way with DIAM. Some are saying that the wines are a little stunted when stoppered with this closure. Of course this begs the question "which DIAM?" if there are indeed various permeabilities (I wasn't aware that there were), save to say that I drink rather a lot of Pierre Peters champagnes which are stoppered with DIAM and they have been the model of consistency. Have they developed normally? As far as I can see, yes. The wines do develop quite slowly, but that may be the nature of the beast or it may be the closure. How can you know? Ironically the one corked bottle of champagne I've had this year was a Peters Chetillons 1999, which was disgorged before they changed over to DIAM.
I should confess up front that I am not in the least a scientific person so my thoughts may best be viewed as anecdotal nonsense.
Though I do drink rather a lot of good champagne and most regard me as observant.

Because my drinking is white wine and champagne centric I sort of ride two horses when closure is the course.

Having put so much faulty white wine, particularly WB and very particularly Leflaive, down the sink I welcome a solution to the problems, part of which I think must be attributed to cork.
In the case of still wines screwcap may be a way to go, and for consistent performance of every day bottles of say NZ Chardonnay up to £20 we find the consistency useful.
IIRC, Kevin from Riverby explained to us at the LaT lunch that it took a while for NZ winemakers to work out that screwcaps had changed the wine flavours because of headspace and reductive notes. ( caveat memory, wine and science involved here).

Though I am not convinced that screwcap is suitable for long term ageing of fine wines, but then I am not sure that many producers now know how to make a wine that is such a treasure.

When it comes to champagne though there really is no chance that screw or crown cap can be widely adopted for so many reasons, not least the way that the brand has been evolved around the celebatory experience of the popping of the cork.
So cork of some type or other is likely to be the narrow tunnell down which the search for a solution is channelled.

Having read the Jefford piece linked above I was struck by the comment of the fellow who said that you dont realise that cork is such an element of the wine until you have stopped using it.
Well Champagne as a region has been using it fo over 300 years or more.
Is it not therefore an integral component in the very fabric that winemakers and we use as a reference?.....and dare I say what we love.
In short if its been built into everything for the whole time, if you rush to remove it can you understand the knock on outcomes.
Anyone who has cooked a dish or taken a tablet knows that there is usually an outcome or side effect.
I just dont think that at present those knock ons are understood.

As to Mytik I belive the tweaking of permeability is a newer development, and for sure my earliest experiences were perhaps with a less sophisticated product.
But from the minute that Billecart -Salmon closed their NV with Diam for me the wines were reductive and dumb and the Rosé NV which was our favourite pinkie, we have not bought since.

That was about 10 years ago.

Since then ( and now we are in serious recall and anecdotal territory )

Orpale 02; the Diam bottles are consistent but not as great as they could be and the squeeaky phut on opening suggests time to drink up.

Moét vintage;disgorgements under Diam not enjoyed nearly so much as those under cork...pretty sure it is the 06 I have had under both.

CH Brut Reserve 08 Base; Although over 18 months since disgorgement seem to be like a bottle disgorged yesterday and something seems missing.

Overall, I have yet to have a Diam closed bottle that truly delivered and whilst the catastrophes are avoided so are the ultimate experiences
It is a bit as if you no longer score N/R, but you also don't ever need the digits 9 or 0 when scoring out of 20.

So for me I tend to avoid when possible the Mytik Diam closure, as I think in top flight wines it strips something out, or as yet we don’t know how to compensate for that which is no longer part of the make up.....after hundreds of years!

The extent to which I feel this is perhaps illustrated in that when I buy Piper Rare 2002 I shall be seeking out a batch under cork to fully realise its potential.
The 28-50 offer is new Mytik closed but not so recently disgorged and yet everyone says “tight”.
Wowed by the price, but it should be the wine!
Hi Mark,

As you've noted with the Pierre Peters, diam brings amazing consistency. Therefore, when conventional cork and diam don't develop in the same way, it's mainly due to the variability of conventional cork. A bit like setting loose a wind-up toy - who knows in which direction it will head..

This 'stunted' effect is not something I've ever observed, but I could see how the people that are expecting the flavours of cork when tasting a recently disgorged wine might feel like something is missing.

Very interesting reading the comments of producers who have experimented with natural cork for the secondary fermentation where they claim that the losses are significant. Unsurprisingly, it's not cork taint that's the problem.......

Actually, when I think about it, I wonder if anyone has tried using Mytik for the secondary fermentation. I'm supposing that there might be some difficulty with using an agrafe with Mytik, but feel pretty sure that this could be overcome.
Yeah that's what I am thinking about.... Even for cork taint, if we say there is a 3.5% ratio, a bottle use natural cork as 2nd ferm stopper gets contact with at least two corks, so the risk is about double. Same applies to other cork faults.
According to the report, DIAM corks actually are not 100% smell free, they smell like wood, probably a bit less than natural corks... I am sure people like Brad can tell us; so the neutrality doesn't mean odour-less.
Yeah that's what I am thinking about.... Even for cork taint, if we say there is a 3.5% ratio, a bottle use natural cork as 2nd ferm stopper gets contact with at least two corks, so the risk is about double. Same applies to other cork faults.
According to the report, DIAM corks actually are not 100% smell free, they smell like wood, probably a bit less than natural corks... I am sure people like Brad can tell us; so the neutrality doesn't mean odour-less.

The TCA removal process involves using carbon dioxide to treat the cork material during production. That process also extracts any readily removable flavour compounds at the same time, hence the neutrality. They are still made of cork though, and therefore do have a woody smell, but the aromas don't seem to diffuse into wine at any appreciable rate. (nothing at all like conventional corks, which can be perceived in the wine soon after disgorgement (for better or worse)