Thursday, July 14, 2011

Should natural winemakers use cork?

I’ve just come back from a cork trip to Portugal which has got me thinking (as it was obviously intended to do). I’ll be writing it up for the Guardian’s magazine Guardian Green but the question that really exercised me in relation to this blog is what you should do if you call yourself a natural winemaker? Should you use cork?

It is after all a more natural material than plastic or aluminium from which screwcaps are made. No tree has to be cut down to supply it - in fact it preserves vast acres of forests that might otherwise be grubbed up for building development.

The cork producers, including the giant Amorim whose plants and processes dominated our visit, have obviously done a great deal to improve the quality of cork over the last few years and claim that it’s much more reliable. I’ve yet to check out the end users’ views on this but my own impression is that I come across fewer corked bottles than I did 5 years ago. Yet many producers, particularly of aromatic white wines have switched to screwcaps in that period.

I would say the majority of natural wines I open do have cork for a closure, despite low levels or no added sulphur. The Amorim research team were suggesting that wines that were low in SO2 would keep less well under synthetic corks but I don't have enough of a scientific background to know if that's likely to be the case. Or whether it applies to screwcaps. They also seemed to be suggesting that cork could release beneficial polyphenols into the wine. (But as a layman I ask myself if they can release polyphenols, why not TCA?)

So over to you. What do you use and why? Do you have faith in cork or mainly use it because it’s ‘green’? Or do you think it’s too high a risk?

Incidentally one thing I was really impressed by - effective or not - was how stunning the cork bark looks at various stages of processing. Take a look at my Flickr stream here.


  1. Fiona:

    You pose some really interesting questions.

    As you suggest, there’s no easy answer. Based on wine competition data, cork taint still hovers around 3%, which totals nearly 1 million bottles a day. (12 billion traditional corks per year X 3% equals 360,000,000 defective bottles of wine).

    For us, and for our customers, that’s far too high of a risk that puts wine quality and brand reputation on the line too often. That’s what we at Nomacorc built our business on – and the reason we continue to invest millions into R&D on wine development (which clearly influences our product development) to continually improve.

    We welcome an informed and educated dialogue – and invite you to come visit us to see for yourself.

    Jeff Slater
    Global Director of Marketing, Nomacorc

  2. A good cork cover is the answer! Keeping it natural and clean! Great post by the way!

  3. Fiona, not being strictly « organic » yet, and wanting to use « minimal » sulfite but not quite « natural » either, I opted for screw-caps for all my wines from the word go, fortified wines and top-of-the-range included.
    You don’t like overlong posts and this matter is to complex to be treated in one paragraph.
    I might forward you a “long” comment one day, to edit or publish as you like.
    Meantime: “corked” bottles are VERY frequent, much more so than the manufacturers admit (I have evidence, no proof).
    But the main issue is the DISPARITY in a case of the same wine after a few years of storage, even in perfect climatic conditions. Cork stops don’t age in a similar way, far from that!
    Finally, the cork people are a huge LOBBY, don’t forget that. Like every industrial lobby, they tend to present a distorted truth. Ain’t that perfect educated British understatment?
    I wanted to write : “They lie as they breath!”

  4. The problem about statistics @Jeffrey is that all sides of the debate can trot them out to support their case. Apcor/Amorim showed me charts to show that the incidence of TCA in corked bottles was way down these days. Who do I believe, without having a scientific background? Has to be the people who are actually bottling or selling wine and even they will have their own agendas. It's complicated, as they say on Facebook but I am interested in finding out more about Nomacorc or any other closure.

    The particular point though is should natural winemakers - of all people - use cork? It would seem to fit best with their overall philosophy but is the fact that many of them use little or no sulphur an issue? Would love to hear more thoughts on this.

  5. Thought you might pop up on this, Luc. And a very restrained comment, if I may say so ;-) I know the cork industry is a huge lobby which is what makes it hard to be dispassionate. But, just for the sake of argument, supposing they have responded to criticism and put their house in order? People make mistakes and rectify them (remember the Austrian glycol scandal?) Have they succeeded in doing that? Clearly not, in your view, which is interesting. Your point about variability is key. Just the sort of feedback I was looking for (you'll be surprised to hear!)

  6. There is absolutely no doubt in my mind that cork should be used. First and foremost is the environmental question: on the one hand, the aluminium industry pollutes the environment (remember that disaster in Hungry just a few years ago?) and so does the petroleum-based plastics industry. We don't need yet more unnecessary plastic or aluminium products, and more pollution for future generations to clean up. On the other hand, the cork industry is positively beneficial to the environment.

    The more I read and participate in closure debates, the less I care about the technical aspects (TCA, oxygenization, etc). Basically, I can't be bothered with the numbers game any more (Nomacork says 5%, Amirim says 0.5% or whatever) The only thing we can rely on (as consumers) is our personal experience.

    For me, the environmental question is much much more important than getting the odd faulty bottle. After all, you can just send it back and order another one!

    I use cork, not only because I'm a natural winemaker, but because I like to think that I'm a concientious and responsible citizen and consumer.

  7. Nice article Fiona on an topic which I am very interested in following. This is the first time i've heard about (beneficial?) polyphenols coming from cork and i'd be keen to learn more about this.

    I certainly agree that all science can be a bit bamboozling at times, hence why we need more detailed reporting (within the industry) on this to be able to sort out the legitimate claims from the false and perhaps more importantly to allow for consumers to eventually make informed decisions rather than being fed soundbites about closures that inspire nostalgia or tug on the heartstrings.

  8. Fiona

    To be clear, the data I mentioned in my comment on TCA comes from the results from wine tastings like the IWC in London (typically 14,000 bottles). Their information illustrates that over the last 6 years, on average, 6% of wines submitted for evaluation are considered faulty. Of those wines closed under bark-based closures roughly 3% exhibited cork taint. It is fair to assume this is a best case scenario given the importance of this competition and hence the extra measures taken by participants to ensure their wines are of the highest possible quality. So, when we at Nomacorc speak about TCA being a problem for traditional bark-based cork, the data source is independently gathered by very reputable sources.

    Additionally, many consumers can recycle alternative closures like Nomacorc because there is a waste stream for plastic material. In fact, in Europe, about 1/3 of all material recycled is some form of synthetic/plastic material. So there is a way to recycle a Nomacorc and have it turned into new products for packaging and other uses. No such waste stream exists for traditional bark-based cork.

    At Nomacorc, we take our responsibility as stewards of the environment very seriously and we work diligently at finding ways to improve. We are proud that in the last 3 years, while growing by double digits we have significantly reduced our use of materials through innovation.

    We are not perfect and are the first to acknowledge it. However, we do have a strong culture of continuous improvement in everything we do.

    Thank you for allowing me to share this added information about Nomacorc. For those interested, more data at

  9. Fiona,

    There are a number of points to make - producers (especially French ones) tell me that the reason they use cork is that the restaurant trade insist on it.

    Secondly it is only in a restaurant that you can send back a corked bottle - especially if it has been down in your cellar for years you cannot ask the winr merchant to replace it and - talking morality rather than law - why should he? - It is the maker's decision to use cork, both the merchant and the purchaser know it is a risk (I'm not talking supermarket or offie party bottle purchases here), why should the merchant carry the risk (and I write as a consumer not a merchant), though, given most restaurants' mark-up, I think it's fair that they carry it.

    The other point on that is merchant and restauranter are in a better position to complain to the producer than the consumer, so here in turn can put pressure on the cork manufactuers/change his closure method.

    Then there is the envoironmental issues which i sinmply do not know - my personal wine drinker's pleasure view is good quality screwcaps (but I believe they can cost the bottler more even than good quality cork - another place where input from Luc would be welcome) for wines to be drunk young, but real questions arise as to development of better quality wines/vins du garde under screwcap.

    I generally do not care for the synthetic corks; similar issues as to development though they do address cork taint issues.

    Graham Kent

  10. Fiona, you rightly pointed out in a not-so-distant past that I (nor anyone) should not monopolize the available space. Therefore, I’m intent on sending you (private e-mail) a series of short notes on the various topics of cork obturation and its alternatives. I have of course more detailed considerations in stock!
    For the time being, we need to address Fabio’s – a very stimulating frequent contributor of yours – concern: not so much the technique but rather the planet.
    In a nutshell : it’s true it takes energy (electricity mainly) to extract aluminium from bauxite but the cork industry is NOT environment-friendly, far from that.
    . Numerous Diesel vehicles to collect the bark from the separate trees, often on sites situated miles apart (especially in Portugal), consuming huge quantities of gasoil in otherwise unspoilt nature.
    . Need to resort to – often two-stroke engine powered – mechanical devices to harvest and cut up the bark.
    . Enormous quantities of water and of chemicals (including chlorine derivatives) needed to “treat” the natural bark and make useful cork of it. Go and see the very own sites of the manufacturers: it is highly educative.
    . Need to dispatch cork stops to far-off parts of the world, sometimes thousands of miles from the production area.
    . Recycling: cork is not easy to re-cycle nor re-use . I don’t say it is impossible.
    . No established network to collect old cork.
    . On the social aspect: cork workers are a very cheap (i.e. badly paid) manpower

  11. @Luc,
    Thank you for your comment. I've also read your frequent and interesting comments though I think this is the first time we've interacted directly (and I hope not the last).
    I'm so glad you commented because I've been thinking all day about Jeffrey Slater's comments (Global Director of Marketing at Nomacorc, no less) and how to reply to them. But I'm not going to do it here, because such slick marketing-speak would require a whole post to address properly.
    As you say, the cork industry is not environmentally friendly in the sense that workers use combustion engines. But I think that's missing the main point. Firstly, ALL industries and activities use combustion engines to a certain extent. Reducing their use is an issue that affects all industries and activities equally, even 'green' ones. Secondly, and without delving into the numbers game, I think there is no comparison with the environmental damage and pollution that the petroleum and aluminium industry causes to the planet, to that caused by the cork industry and its machinery. It must be orders of magnitude greater. Thirdly, I'd emphasize the question of sustainability: economic and environmental sustainability. Aluminium and petroleum are finite resources and their extraction and processing cause immense environmental and health-related damage. Cork forests are sustainable, provide jobs for rural families, preserve ecosystems and culture, prevent desertification, etc.
    I think that some products derived from the aluminium and petroleum industries are in fact very useful, even essential for mankind; but for closures for bottles of wine???? Totally unnecessary. The only beneficiaries are the owners/shareholders of companies like Nomacorc and the losers are everybody else living on the planet and our children and descendants who will be living in a dirtier and more polluted and toxic environment. The closure itself may be cheaper in terms of the cents that the consumer ultimately pays for a bottle of wine, but what about the unseen cost that the polluter causes? Aluminium and plastics manufacturers use the environment as if it were a dump, and pass the cost on to ‘others’, ie present taxpayers or future generations.

  12. This frustration of blogs !!!!
    I agree with you on a number of issues, Fabio, and would like to prove you wrong on others. But we’ll leave it at that for the sake of “sharing the space”. At least our readers have understood what we talk about and that there’s more to this than just a “corked taste”, already bad enougfh on its own. Mi me gusta también la planeta !

  13. I know one reason why producers like Pyramid Valley use screwcaps is just sheer availability of the materials (bottles and caps), but I remember Mike Weersing opening a bottle of Chave Hermitage one day with me, which was so generous of him (one of my favourite wines) and it being ever so slightly corked. He rushed out and grabbed another bottle, but I felt really bad about it...

  14. Ultimately it shouldn't matter what the closure is made of - the marketing department can worry about that.

    All that any winemaker wants is a closure that doesn't taint or scalp, that’s consistent and preferably has a range of OTRs. Oh and one more: it stops the wine falling out of the bottle.

    A wine is almost certainly going to spend more time in its packaging that it will do under the winemakers' tenure and unless a closure can meet the these criteria the winemaker is 'flying blind'.

    Like it or loath it brands such as Jacob’s Creek and Turning Leaf became so successful in the late eighties/early nineties, in part, due to their comparative consistency. Irrespective of the “statistics” inconsistency, be it from tainting scalping or variable OTR, is incongruous with success.

  15. No one seems to have mentioned Diam. You can almost have your cork and eat it.

  16. @James Gabbani, with a faint smile.
    In my ideal world, as much as in my personal real world, the “marketing department” and the winemaker are one and the same guy (or lass). They are the same as the pruner, as the tractorist, as the grafter (have not done that yet, but want to learn the skill), as the surface cleaner, as the sales person, as the export manager, as the accountant, as the caterer, as the PR man, as the leaflet translater, as the carpet cleaner, the window cleaner ...
    Do you remember Leo Sayer?
    “Well I'm a one man brand
    nobody knows nor understands
    is there anybody out there wanna lend me a hand
    with my one man brand ... “

  17. I grow tired of cork industry generated (and sponsored) propaganda that is fed through journalists on the subject of closures. Who claims that the "natural" (and why do we choose to use this word?) corks are greener than screwcaps? Who has unbiased data to back this up? I've never seen any.

    1. The transport of corks, by virtue of their non-compressible greater volume, leaves a much larger carbon footprint than screwcaps.
    2. Most importantly on every cork-sealed bottle I've had there is a polylaminate, polyvinylchloride, or tin capsule to hide the frequently mouldy, dirty piece of bark! The capsule must be part of the argument unless cork users stop using them.

  18. To answer your question relating to appropriate closures for "natural" wines, oxygen permeation rates for cork is on average lower than most synthetic closures, but higher than screwcaps with a tin liner. It would seem appropriate to use screwcaps for wines that are fragile to oxygen such as those made with low SO2 additions.

  19. Matt Thompson is talking some seriously good sense.

  20. @Matt Thompson,
    I'm tired of the propaganda generated by BOTH sides (cork vs. petroleum/aluminium), even though I'm a firm proponent of the the use of natural cork.
    I know it's a lot to ask, but I think we should ALL try to see beyond the propaganda and do a bit of due diligence, ie check out some facts and figures that are not actually published by Nomacork, Alco or AMORIM.
    I've done that (a little!) and I can see at a glance that the pollution and environmental damage caused by the aluminium and plastics industries is hundreds, if not thousands, of times greater than that caused by the cork industry.
    PS. Capsules! Yes, for want of an environmentally friendly capsule, I sell my bottles 'naked'.
    PPS "to hide the frequently mouldy, dirty piece of bark!" is hardly respectful or useful language to use in a debate.

  21. Fabio, you are sweet, but I don’t think you should judge which language is appropriate or not, as long as it remains polite. You start the conflict ad hominem with Matt yourself. Moreover, you originate from a country heavily involved in the cork trade and as such, are highly biased (willy-nilly). Finally, the part of cork used worldwide for bottle cork stops is MUCH more important than the percentage of aluminium that goes into screw caps, compared to other items. Your reasoning is faulty on that point, I’m afraid to say. I like your general approach a lot and believe we have a lot in common but I sincerely think that, in this matter, you are loosing perspective. Green, natural, not-chemical should not become a religion, but the result of careful thinking and deliberate choice. If we would walk your path all the way, then there’s no need to make wine at all. What good is it?
    Personally, I used to be an MD and an unpaid (that’s important) wine journalist in a previous life, and a “lefty” at that too. I come from a non-bark producing and non-aluminium processing country – being Belgian born - and I have no connection whatsoever with large scale industry. Yet, through experience with a LOT (I say between 4 and 7 % and can back this figure with some data, but no hard evidence, I agree) of faulty corks and aromatic deviations in bottles from the same case, I OPTED for screw caps from the word go when I bottled my first vintage (2005). I only try to explain my choice with sound arguments. On the other hand, I contemplate refurbishing my bath-room as soon as I’ll have some money and think I will use cork tiles to cover the walls. There, the advantages prevail.

  22. Thanks for all your contributions to what is a fascinating debate. It certainly generates a lot of heat on all sides, the main problem being how to assess the claims and counterclaims without a PhD and a multi-million pound research budget of your own.

    A few points:

    * It is possible to be open-minded about this and say that there are horses for courses with closures depending on the style and price of wine and how long you want to keep it. That's something both the cork and synthetic producers seem unwilling to acknowledge.

    * I don't think just because as a journalist you listen to what the cork industry - or Nomacorc for that matter - has to say that you're 'feeding through' their propaganda. I think it would be negligent if you simply trotted out past prejudices

    * Regardless of my view of cork I'm not sure it's right that if an industry holds its hands up and says we got it wrong and spends a great deal of money and energy to trying to improve their performance they should be castigated as if they've done nothing.

    * That said, you still come across corked bottles with too great a frequency. Is that acceptable? Depends on your viewpoint. A lot of people get pleasure out of handling cork and believe it adds to their enjoyment of wine. I don't think the odd rogue cork puts them off. For producers, retailers and restaurants though it must be infuriating. Is 3%, which seems to be the going figure, an acceptable failure rate? Many would say no but what else in life is 97% perfect?

    * I would have thought for European natural wine producers at least (and what 'natural' means is another debate but I think we know who we're talking about) cork would be the most obvious option. It is a natural, locally sourced material. There are obviously issues about shipping it half way around the globe.

    Anyway I'm carrying on my research, talking to as many people as I can about the subject. Thanks again for your contribution (and keep chipping in if you want!)

  23. YOU are more than 97 % perfect on this issue, Fiona. We are even given a chipping/shipping pun as a bonus in the end.
    Keep the aspidistra flying !

  24. I don't think that there is a magic percentage of corks contaminated with trichloroanisole. Since the perception of this and other related destructive compounds in corks varies so much from person to person so does the percentage. Also if you know the wine, you find more damaged bottles. If you open multiple bottles you find more because you can compare them. In my experience the lower the person's perception level for tca, the more likely they are to turn to screwcaps. Conversely the poorer they are at detecting tca, the more likely they are to defend corks. It can be like arguing about colour tone with someone who is colour-blind. The difference is that most people who are colour-blind know that they are.

    As far as reporting information derived from cork producers; that's fine as long as the information is cross-referenced or an alternative viewpoint is sought. I find it disturbing when a journalist goes to Portugal hosted by the cork industry and returns to write about the evils of screwcaps and the purity of the cork industry and its products.

    Sadly the screwcap producers seem to be happy to leave it to us poor wine producers to justify ourselves in our unbiased choice of a closure that we judge to be the best at getting our wines to the consumers in the best possible state. We've made these wines with hard work and passion. All we want is for people to be able to enjoy them without having to waste most of the night discussing whether it might be corked or not. It should be about what is IN the bottle.

  25. Couldn't agree more, Matt and I'd never let the way a bottle was sealed affect my own decision whether to buy it or recommendations to others. You have to trust the winemaker to get it right - and the retailer to return it if it's faulty though that gets progressively more difficult as time goes on.

    Interesting point though about picking more faults up if it's a wine you're familiar with. That's not always been my experience. I've tasted wine with winemakers who've been unable to see it's faulty - I think a sort of palate blindness can set in. But certainly some people are more susceptible to TCA than others.

    Can you email me BTW at fibeckett AT live DOT com as it would be interesting to pursue this further

  26. Luc,
    I didn’t for a minute wish to start a conflict with Matt Thompson, who makes some good and valid points, nor with anyone else. On the contrary, the tone and content of this debate is one of the best I’ve participated in, and I had no wish to see it degenerate into a flame-war. I just felt that the phrase in question may have been the start of a downward slide. Imagine the string of words I could use to describe a screwcap or a plastic stopper!!! A good soundbite maybe but it would contribute nothing to this debate, no?

    Yes, I may be biased due to where I live, but I try hard to rise above my own limitations and see the bigger picture. And the bigger picture, for me, is the environment. I don’t think I’m losing perspective, in fact I think I’m gaining it, the less I worry about oxygenation rates or TCA rates or whatever, and the more I think about the overall environmental problems that affect us all.

    This is not a religion as you suggest. Religion (again, for me) means blind faith in something, despite any evidence available. I like to think that my position on environmental issues, such as pollution or sustainability, is based on rationality and evidence.

    There’s no need “to walk any path all the way”, ad absurdum. Humans have been making wine since the dawn of civilization, and no doubt will continue to do so for a long time! The question is HOW to make it, ie using what resources and materials? Polluting or non-polluting? Sustainable or non-sustainable?

    Congratulations on your choice of bathroom wall materials :). It’s a contribution to the use of sustainable and eco-friendly resources, and towards a cleaner, less polluted planet. I think our decisions as consumers, not just as producers, are important too!

  27. I like your last contribution a lot, Fabio. Yes, we have s’thing in common: in the end, common sense should prevail and there’s no need to agree on everything to stay good friends. This does not preclude a vivid discussion and the use of strong but pertinent arguments.
    By the way, I met Alejandro Fernández of Pesquera fame in Stuttgart, April 2009. He had just been operated upon for cataract, as well as my own “madre”. But she used to be an eye-surgeon – so she knew – whereas he was not. He was anxious about his eyesight recovery and I could reassure him it would come out fine with time, “dentro de poco”. On the other hand, I had purchased some wine from his during a trip to the Duero, way back in ’89 or so. It was Gran Reserva 1986, just released, and I had not touched it since. I enquired about when I should ... uncork it. Mind you, my Spanish is broken. His immediate answer was quite firm: “ahora” and there he was very positive !

  28. Emile van Schayk, Orkney Wine Company
    We are the most Northerly (fruit wine) winery in the UK,and make 15 to 20.000 bottles a year for almost 10 years now, so that's about 200.000 so far (we just moved to a bigger winery and we are going to produce a lot more soon). All our wines are tested in an independent wine laboratory who test wines and spirits from all over the world before we bottle it and we use only natural corks. We do not add any sulphites at all! The wines and liqueurs are also suitable for vegetarians. We use the best corks we can get, that is not always easy because we are only a small producer. Price is not an issue we go for the best quality. Do you know that the laboratory had tainted (corked)wines that had screwcap closures? This is true,I will ask the wine consultant if he wants to join in on the debate.
    Over the years we had no more than 12 tainted wines (we use 45mmx 25mm winecorks)just this week we had a raspberry liqueur that was very cork tainted. We use T stoppers for the liqueurs, so far in those 10 years we had about 5 bottles of liqueurs tainted. I do a lot of testing myself with synthetic stoppers etc(you can really blind taste the difference: plastic is no good at all) but for us only natural cork and nothing else no sulphites either.

    Someone mentioned the capsules used on cork-closed bottles. Every screw-cap I have seen uses a lot of extra material to make it look like a capsule.(they can make 3 screwcaps owith the same material if they make them a lot smaller !?
    And for the people who are worried about the distance the corks might travel, do they also worry about where the wine they drink comes from?
    cheers everybody and keep enjoying a good glass of wine

  29. There are a few points to make here. Firstly Fabio thank-you for your considered view point. I do suspect thought that the failures of corks undermine any environemental argument as the entire bottle is then a total waste at the point of "consumption"

    Perhaps more importantly, why won't this discussion die? Why aren't we free to choose the best closure for our wine and let the media and public deside whether the wine good or not? As I see it the cork industry won't let it take its course. They keep flying journalists out to Portugal and give them information about the purity of their product and the evil nature of their competition. How many journalists have been to the screwcap producers and synthetic cork facilities? That's a real question by the way.

    Fiona and Emile you both underline my point about some people being less capable of detecting tca at low levels; Fiona you through your accounts of tasting with some winemakers, and Emile through your recounts of your personal experiences.

    I am not closed-minded about this. I have bottled hundreds of wines under cork and understand the process and the results. If I was convinced that they were the best closure now, I would be happy to use them. At this stage I am not, and feel that screwcaps get the wine to people who buy them in the best condition. These people have a right to expect the wine to taste as it should. They should be more concerned about what is in the bottle, rather than the closure, and so should we.

  30. I know that this is now academic but I have the results of a trial that we've just finished in the US. We bought 18 bottles of each of the 10 best selling wines by volume in 3 price categories, tasted and technically analysed for free & total SO2 and TCA every bottle.

    The aim of the study wasn't to find out whose closure was best but to find out what was the chance that a consumer would be able to pick two bottles from a shelf at a given time in a given area and for them to be the same.

    In other words we were looking at bottle variation not the cause.

    It's high. Very high and everything we can do should be done to reduce this. Bottle variation costs. It costs money and carbon and the closure is a consideration but so is shipping, glass, wastage, etc.

    "Natural Wine"? The title may be dubious at best but it doesn't mention anything about the packaging.

  31. Good morning,
    is always important to choose the cork, is to maintain quality of the wine (cork taint should be avoided during the production of the same chapter and depends on the attention of those who produce the cap), and because it is a source of environmental impact to zero. In fact it is a work that, from the moment the cork is removed from the plant, is made completely by hand without the aid of mechanical means.