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Screwcap failure rates??

PostPosted: Sun Oct 22, 2006 8:45 am
by Redwinger
Have any studies been done of the failure rate on screwcapped wines? If not wine, how about other products under cap?

The reason I ask is that I was opening a case of screwcapped wine down at the shop a few days ago and noticed the cardboard between the layers had a stain about the size of a silver dollar. Obvious leakage. I suspect this would have gone unnoticed if the case had been the traditional "standing" type.

Again, I'm interested in any studies that have been done.
TIA

Re: Screwcap failure rates??

PostPosted: Sun Oct 22, 2006 10:45 am
by Michael Pronay
Not exactly a study, but bottle producers admit that microfissures at the mouth of a bottle can occasionally happen. This leads to leakage (when stored on the side) or oxidation (when stored upright). The bottle producers admit a failure rate of one bottle out of 2,000 to 3,000. That's what Karl Fritsch, a producer here in Austria (Donauland) has been told.

Re: Screwcap failure rates??

PostPosted: Mon Oct 23, 2006 6:05 pm
by Ruth B
Redwinger wrote:Have any studies been done of the failure rate on screwcapped wines? If not wine, how about other products under cap?

Again, I'm interested in any studies that have been done.
TIA


The Kiwi's have done a fair bit of research. The linked artical here is fairly long, but study results are included.

http://www.kumeuriver.co.nz/news_full.asp?ID=22

I got the link from Coffaro (since David is now using screwcaps)

Re: Screwcap failure rates??

PostPosted: Mon Oct 23, 2006 6:18 pm
by Hoke
I got the link from Coffaro (since David is now using screwcaps)


Ruth, I've only seen the Coffaro white in screwcap. Do you know if he is planning on doing the same with his reds, or is he waiting a while on that?

Re: Screwcap failure rates??

PostPosted: Mon Oct 23, 2006 6:40 pm
by Ruth B
Hoke wrote:
Ruth, I've only seen the Coffaro white in screwcap. Do you know if he is planning on doing the same with his reds, or is he waiting a while on that?


Yup, we just got our case from Coffaro --it is mostly reds -- and even the Aca Modot (his bordeaux blend) is screwcap. Fine by me.
David included a flyer about the closers with the case.

Ruth

Re: Screwcap failure rates??

PostPosted: Mon Oct 23, 2006 6:47 pm
by Hoke
Woohoo! Good that he's doing his reds, and that he's explaining why he's doing it.

Twist and enjoy, Ruth.

Re: Screwcap failure rates??

PostPosted: Tue Oct 24, 2006 4:08 pm
by Ian Sutton
I suppose we should clarify failure. For me your question sounded like a measure of complete or at least significant failure of the seal.

However there's also failures that are potentially more contentious
- Reductive aromas (personally I've yet to experience this, but for some people it's an issue). This is pretty contentious and I'd rather we didn't get into a debate about it :oops:
- Other winemaking faults: Screwcapped wines can still be tainted by TCA (when present in barrels or winery), Brett, plus various other lesser problems.

The reason I mention this is I think it's fair to compare not just failures, but magnitude of failure. Some TCA in cork sealed wines could feasibly have come from the barrel, not the cork. A very small %, but let's have a clean fair fight :) . Also some failures such as reduction are very minor, and indeed lower levels of TCA will only slightly change the flavour profile of the wine, which will remain drinkable.

What I'd love to see, is a single study (or more realistically a collection of studies) where the results are organised something like
Severity
Fault Undrinkable tolerable barely perceptable
TCA 8 4 7
Brett 5 9 2
Oxidised 5 1 0

Based across various wines/seals

At this stage, such a study is both pie in the sky and also not particularly scientific as it still relies heavily on human interpretation. It also could only be a snapshot as methods are changing every year.

Maybe one day we'll get something balanced and scientific, but I think we're most likely to end up relying on limited personal experience and personal perceptions. My perceptions currently favour Screwcap over cork with cork variants (e.g. Diam) coming up on the rails - I'm yet to feel comfortable with this latter category yet.

Having said all that, I am happy to see more and more results published, even if that means accepting human variation that is implicit in them.

regards

Ian

Re: Screwcap failure rates??

PostPosted: Tue Oct 24, 2006 10:05 pm
by Victorwine
Hi Ian,
Very nicely said and I agree. Being an amateur winemaker I do take reduction problems seriously and I’m sure most quality conscious professional winemaker also takes it seriously. Because it is possible that a finished wine can have an unpleasant and undesirable “reduced” character reduction should be added to the list of faults.

Salute