Do you prefer Synthetic Corks or Screwcaps?

After having recently tried several wines bottled under screwcap (a few of them even being our Ontario VQA wines), I have come to the quick conclusion that I prefer the new-generation screwcap closures to the plastic cork option. The reasons for my decision, to which I came after literally years of indecision on the matter, are:

(1) I have routinely picked up disconcerting "vinyl"-like scents in almost every wine I've ever tried that's been closed by a synthetic cork. The corks themselves often have that plasticky smell when you extract them, and I get vinyl notes in the wine too. I don't know if it's a function of the wines that are thus bottled or what, but the majority of reds I've had that have had synthetic corks have had thin palate-feel. Could it be that synthetic corks just don't marry well with reds? (2) Synthetic corks tend to be difficult to extract; they require more force, causing me to be selective about which corkscrews I use on them. (3) Screwcaps are functional and don't require any special tool to open. (4) Screwcaps don't impart any odour whatsoever to the wine.

Just before posting this query, I was looking at these Austrian 250 ml bottles and came to the conclusion that if the effort is made, screwcapped wine bottles need not have a plonkish image. I think that styling can completely overcome the fact that for years, only the worst wines were bottled under screwcap - at least here in Ontario, and probably in lots of other places (save Europe it seems - I think they've done what the Austians here have for quite some time, haven't they?).

What's your take?

[Robin Garr]

Paul, the jury is pretty much in, I'm afraid. Synthetic corks just aren't proving out. Your finding of a "vinyl" character is idiosyncratic, and I might suggest you try some double-blind tests to confirm it; but it's becoming very clear that synthetics simply aren't good for more than a year or two, after which wines age/oxidize way too quickly. At this point, I'd rather take the risk of cork taint from a natural cork than wine tired from storage under synthetic, unless the wine is a very recent arrival (current or past year's vintage) in which case I'm OK with it.

Screwcaps are fine. I've very occasionally seen bottles showing a little reductiveness, but nothing irreversible. When I see a screwcap on a bottle, I'm happy.

I guess I should add, Robin, that Flat Rock Cellars bottles all their wines under screwcap, and they are making what I think is the finest Pinot Noir I've tasted from Niagara yet. It makes a point to see them putting faith in this closure for their signature red.

Screwcap over synthetic everytime.

But people buying - or not buying - a screwcapped wine are making a definite choice, but few of us know a wine is closed with a synthetic until moments before opening when we remove the capsule.

I love screwcaps for their ease of opening - just a quick twist as the bottle is on its way to the table and you know the wine will taste clean and fresh. My heart sinks with synthetics and I have to look out my backup corkscrew which has a plain metal screw, as these synthetics strip off the teflon from decent corkscrews.

I endorse your post wholeheartedly, Robin, but would just like to add, the alternative cork closure, "Diam", seems to be very well regarded/received by wineries, winemakers and wine lovers alike over this side of the world.

It's worth reiterating winemakers must watch their sulphur levels with the use of screwcap.

, but would just like to add, the alternative cork closure, "Diam", seems to be very well regarded/received by wineries, winemakers and wine lovers alike over this side of the world.

I've never had a wine closed with Diam - has anyone here???

[Robin Garr]

the alternative cork closure, "Diam", seems to be very well regarded/received by wineries, winemakers and wine lovers alike over this side of the world.

I haven't (knowingly) seen one on this side of the water, David. I would like to.

Just a comment.

I was in Pennsylvania back in march, and bought some wine from two local wineries. One was Cloverhill, the other I can't recall at the moment. At the other winery, they suggested I hold back a bottle of their flagship red for at least five years, and it was closed with a synthetic cork. So, obviously, they think it will be fine. I'm not so sure.

Peter,

Here's some discussion off our local board to kick you off. I'll do some more digging if you want when I'm not so busy.

http://www.winestar.com.au/forum/viewtopic.php?t=11997&highlight=diam

http://www.winestar.com.au/forum/viewtopic.php?t=11934&start=15

Peter,

Here's some discussion off our local board to kick you off. I'll do some more digging if you want when I'm not so busy.

David - I appreciate your response, but the question I asked was whether anyone here had experience of opening a wine closed with a DIAM.

My point being that until there is enough of these closures in general use and with wines that have been aged in them, then all the claims made for them are just that -- claims.

I'm old enough to have heard claims from the cork industry before.

My concerns with this product is that it is not a cork as we know it, it is a reformed cork shaped object made from cork dust stuck together. We know about traditional cork's incredible elasticity, and we know that cheap agglomerate corks don't have the same elasticity, so I wonder how DIAM holds up over the years, and if there any effect from the binding agent?

The thread you point to has Dean Bannister of Oeneo saying

Our specification for Ageing potential is four years, we say this because this is how long our trials have been going for in the UK and for 36 months with the AWRI. By early 2006 we will say 5 years because we have the evidence to support this.

For keeping four-five years I'd rather have an easy to open screw-cap and for longer aging -- well, there is no evidence.

Peter, the binding agent, as to my knowledge (from the Diam presentation here in Vienna) is PU foam.

As to the claims of the cork industry, Diam definitely is in another league. Supercritical CO2 extraction does remove *any* unwanted substances, TCA and any other molecules. It's a totally different approach than the other known processes (Delfin, Rosa, suberase etc.)

TCA-freeness has been proved by two independent studies, one in AU, one in UK

As to their 48 month warranty: That's what their oldest bottles are. They will add one year after one year has passed, that's what Dean told us, and that's what they told us here in Vienna.

This does *not* mean that Diam is only a midterm closure.

As to warranty: How much do you get from your cork manufacturer? Right: zilch, nada, zero.

As to the claims of the cork industry, Diam definitely is in another league.

So they say. All I am saying is "let's see".

Your post mentions TCA; so its TCA free, well so are screwcaps. And screwcaps don't need a corkscrew and they don't impart the taste of cork to the wine.

This does *not* mean that Diam is only a midterm closure

So they say. All I am saying is "let's see".

Paul, to me drinking from a bottle with a plastic plug seems a bit like having sex with a condom. I wouldn't do it unless I was faced with the last bottle on earth. The other option seems outright alien.

As to the claims of the cork industry, Diam definitely is in another league.

So they say. All I am saying is "let's see".

No, "they" don't say that. Besides, "they" never gave nor give you any warranty at all. In the Diam case the proven TCA-freeness and absence of bottle variation are definitely manifest since the first trial bottlings 4 and 5 years ago.

Your post mentions TCA; so its TCA free, well so are screwcaps. And screwcaps don't need a corkscrew and they don't impart the taste of cork to the wine.

Diam doesn't impart any taste, and there is no bottle variation.

Besides, the issue is not Diam vs screwcaps, both are OK, imnsho. The real issue is Diam vs all other corks. The latter don't give you any warranty at all.

This does *not* mean that Diam is only a midterm closure

So they say. All I am saying is "let's see".

If I was a winemaker, my choice would be screwcaps or Diam. As a consumer, my choice is screwcap, unless I know that a given wine is stoppered with Diam. In the latter case I wouldn't mind between these two closures.

Covert, you're supposed to take the plastic plug out before you drink from the bottle.

Me, I pour it into a glass first.

Diam doesn't impart any taste

Corks do. DIAM is made from cork.

I have not had a DIAM closed wine and no one here has responded that they have. I'm interested in how many bottles of DIAM closed wine you have drunk?

You are very certain about something that has a 4 year track record in a test environment. I wish I could be so trusting, but I guess I've heard too many promises of future performance before.

Time will tell.

Peter, after the processing via supercritical CO2, which at a pressure of 100 bars washes out anything that can impart any type of aroma, the cork granulate is 100% tasteless. Cork loses its elasticity during that process, that's why you need these "microspheres" mentioned in that Australian thread.

There are a few discrepancies between what Dean, the Oz rep for Diam, claimed and what the French guy presenting Diam here in Austria said. I asked these questions very recently on that Oz forum http://snipurl.com/r0n1 — without response yet..

There are two studies that certify 100% taint freeness, and no bottle variation has occurred in all these tests.

I wonder why you would consider a "test" environment (that includes heating and cooling for test purpuses and all type of abuse) somehow "better" than normal ageing in a cellar? If any, it's the other way round.

As to the numbers of wines tasted, roughly a dozen, including a sparkler stoppered with Diam's sparkler brother, Mytik.

Don't you think the growers using Diam — both in the test phase and now after the commercial launch — would have been the first to cry "Fire!" if anything would go wrong?

Btw, Diam is the first cork product ever to give both a 100% taint free and a 100% tightness guarantee. None of the so-called solutions of the past — you and I have heard them touting it more than once! — ever gave any type of warranty.

Peter, it's not the warranty that give me this confidence, it's the understanding of the type of process. At the presentation there were two guy from Natex who explaiend the treatment. They come from a completely different side: Their normal job is constructing aroma extraction machinery for the perfume and the food industry, including decaffeinating coffee.

I do trust them, confirmed by the results of two studies and by test running up to four and five years.

There is one inconvenience: Supercritical CO2 treatment leads to loss of elasticity. They had tried to treat whole corks in the past, but at these pressure levels the corks were irreversibly deformed. That's why you need these polymer microspheres to bring back elasticity.

If I have any doubts about Diam, it would be the elasticity in the long and very long run — but definitely not about taint-freeness and bottle variation.

Peter, after the processing via supercritical CO2, which at a pressure of 100 bars washes out anything that can impart any type of aroma, the cork granulate is 100% tasteless. Cork loses its elasticity during that process, that's why you need these "microspheres" mentioned in that Australian thread.

There are a few discrepancies between what Dean, the Oz rep for Diam, claimed and what the French guy presenting Diam here in Austria said. I asked these questions very recently on that Oz forum http://snipurl.com/r0n1 — without response yet..

There are two studies that certify 100% taint freeness, and no bottle variation has occurred in all these tests.

I wonder why you would consider a "test" environment (that includes heating and cooling for test purpuses and all type of abuse) somehow "better" than normal ageing in a cellar? If any, it's the other way round.

As to the numbers of wines tasted, roughly a dozen, including a sparkler stoppered with Diam's sparkler brother, Mytik.

Don't you think the growers using Diam — both in the test phase and now after the commercial launch — would have been the first to cry "Fire!" if anything would go wrong?

Btw, Diam is the first cork product ever to give both a 100% taint free and a 100% tightness guarantee. None of the so-called solutions of the past — you and I have heard them touting it more than once! — ever gave any type of warranty.

Peter, it's not the warranty that give me this confidence, it's the understanding of the type of process. At the presentation there were two guy from Natex who explaiend the treatment. They come from a completely different side: Their normal job is constructing aroma extraction machinery for the perfume and the food industry, including decaffeinating coffee.

I do trust them, confirmed by the results of two studies and by test running up to four and five years.

There is one inconvenience: Supercritical CO2 treatment leads to loss of elasticity. They had tried to treat whole corks in the past, but at these pressure levels the corks were irreversibly deformed. That's why you need these polymer microspheres to bring back elasticity.

If I have any doubts about Diam, it would be the elasticity in the long and very long run — but definitely not about taint-freeness and bottle variation.

Michael

You are coming over like a salesman for the product. There is no need to keep bashing me over the head with marketing details because my stance is to wait and see.

Lets see how this mash of cork dust and polymer microspheres perform over 10+ years.

But to be honest, what does DIAM promise that screwcaps do not already deliver? OK, the 'romance' of opening a bottle and wineries do not need to change their bottling lines. But as a consumer I find a screwcap more convenient to open.

[David M. Bueker]

Paul, to me drinking from a bottle with a plastic plug seems a bit like having sex with a condom.

Both are safer than an uncovered cork.

Peter,

I, too, haven't seen enough of Diam-closed bottles to come to any "long-term" conclusions. But eliminating the curse of TCA is, at least, a step in the right direction. I regard screwcaps as the best form of closure currently available, albeit, as I mentioned in my original post, the number of wines (red and white) revealing rubbery/gunflint reductive characters requires winemaker's to be vigilant with their use of sulphur.

Sorry Peter,

in no way my intention was to bash you over your head. What I wanted to say is: Please don't put Diam in the same corner as Delfin, Rosa, suberase treated or steam cleaned corks.

Diam should be seen as an alternative to crown caps and screwcaps.

I am totally with you on the advantages of screwcaps. My first article about them appeared in 2003 (the very first article on that subject in Austria): http://www.vinaria.at/sub11_vi.asp, the second in 2005: http://www.austrian.wine.co.at/frischgepresst/alacarte200501.htm.

Don't misunderstand me. I am totally with you and 100% for screwcaps. My en primeur Bordeaux purchases of the 2004 and 2005 vintages were two cases each of screwcapped Château d'Agassac, the only Bordeaux offering the choice of closure.

Maybe Diam would be a possibility for those bullheaded Bordeaux proprietors to think about a change. It would be nice to get my wines at least under Diam, as they seem extremely reluctant to offer a screwtop alternative.

Btw, the second posting on this page is from an Oz winemaker: http://snipurl.com/r1k0.

My position is quite clear: getting rid of bark and synthetics, bring along screwcaps, Diam or crown caps (the latter for sparklers).

, but would just like to add, the alternative cork closure, "Diam", seems to be very well regarded/received by wineries, winemakers and wine lovers alike over this side of the world.

I've never had a wine closed with Diam - has anyone here???

There are a ton of kiwi winemakers using Diam now. I even had a bubbles with a Diam earlier this week. I just wish they would let the consumer know there is a Diam inside.

[Robin Garr]

My position is quite clear: getting rid of bark and synthetics, bring along screwcaps, Diam or crown caps (the latter for sparklers).

Michael, but is not Diam a bark product? And is it not made by Oeneo, the French firm that brought us the ... Altec?

My position is quite clear: getting rid of bark and synthetics, bring along screwcaps, Diam or crown caps (the latter for sparklers).

Michael, but is not Diam a bark product? And is it not made by Oeneo, the French firm that brought us the ... Altec?

Robin,
It is the same company that made the Altec, but they have now changed their name to Oeneo. Not surprising as Altec was a total failure, whereas Diam is proving anything but. The uptake for DIAM by kiwi winemakers has been quite startling, not as startling as the uptake for screwcaps, but still very startling. I haven't had a corked or oxidised wine from a DIAM yet.
Cheers,
Sue