Cork or screwcap? The great closure debate rolls on and on and may seem to have been round the houses and back in recent years, but new evidence points to cork as actually not being the baddie that it has been made out to be. Certainly, the wine faults analysis from the International Wine Challenge's Sam Harrop MW last year made very interesting reading. Of an impressive 13,477 wines tasted at the Challenge, 7.2% were deemed faulty by the judges and the chair. Mr Harrop's main conclusions on these were as follows:
Cork and screwcap-closed wines showed almost the same number of faults. (Of the 13,477 wines tasted, 2.8% showed taint relating to cork, while 2.2% closed under screwcap had high sulphide faults).
Less than half the faults identified related to closures (Within that 7.2% faulty wines figure, under half showed closure-related faults while one third were attributed to chemical faults, and over 15% to microbial faults such as Brett and rot).
Cork taint only accounted for just over half of those closure-related faults Other faults were related to oxidation, high sulphide and incorrect wine making.
Cork taint faults are considerably lower than the industry perception The IWC in-depth analysis showed that just 2.8% of the total competition wines showed cork taint, or TCA. This is way below the 5% to 10% figure normally, and mistakenly, quoted.
Many other faults, such as TBA, high sulphide, and Brettanomyces have been present in wine for as long as cork taint, but have largely been ignored in wine spoilage figures until now. This may all seem seriously technical for the man in the street, but it does suggest that cork has been cast in the role of fall guy by both wine trade and consumer. And TCA - which causes that musty smell - can develop not only via the cork, but also from particles present in paint, disinfectant and wood preservatives, all of which can be found in the winery.
Certainly many bottles that are returned by customers as "corked" either appear to have no faults at all or one or more of the faults mentioned above. It's clear that many of us (both the wine trade and its customers) are not as clued up on wine faults as perhaps we should be. It is also clear that screwcaps have their own problems, especially those connected with high sulphide levels. Certainly it is only relatively recently that wine faults have been analysed in detail at all.
All this tells us that the closure debate is a great deal more complex than was first perceived by the wine trade, a point eagerly taken up by Amorim, who are the largest cork producers in the world, with a 25% share of the global market. Their "cutting-edge" plants south of Porto and east of Lisbon in Portugal produce approximately 3 billion cork products a year.
Over the last three years Amorim have invested many millions of Euros in improving the quality control of the cork products they make, from the initial harvest by hand, to the latest storage, processing and washing techniques, to state-of-the-art automated punching and cutting and stringent laboratory testing of every batch produced. All these advances have resulted in an all-time low for TCA complaints and Amorim continues to build on its sales of cork closures globally - almost doubling those sales over the last 10 years.
So what of the future? We are clearly moving towards a better understanding of the relative merits of both cork and screwcap closures. Over 80% of the world's annual production of 17 million bottles is still being closed by cork. As the benefits of micro-oxygenation in wine and the positive environmental impact of cork stoppers in both carbon footprint and recyclable measures become increasingly better understood, it certainly seems that cork is here to stay - as it has down the centuries.