Have you ever wondered which stopper is best when it comes to wine? Cork or screw top? Read on and find out!

I’ll admit – I like wine.  Sauvignon blanc, Prosecco, Malbec, and Merlot are my tipples of choice.  Come Friday night, after the baby is in bed, you’ll more often than not find me with a well-deserved glass of wine in my hand. I’ve even got a guide to ethical wine right here.

Over the past few years, plastic stoppers and screw-top wine bottles have infiltrated the wine market.  At first, when screw tops started appearing I thought “how convenient” – no more searching for a bottle opener, and no more corked wine.  However lately I’ve started to wonder “is cork eco friendly”, or are their screw-top equivalents more environmentally friendly?

Surely a Screw Top Is Best?

My initial thought was surely yes, screw tops are more environmentally friendly. Especially as trees have to be cut down to extract the cork, whereas metal can be recycled.  

Then I started looking into it, and as it turns out I was completely wrong.  What I found was that cork is eco-friendly as cork is one of the most sustainable materials in the world.  Meanwhile, the dominance of screw tops on wine bottles is actually threatening ancient Mediterranean cork oak forests.  Screw tops and plastic stoppers also contribute to widespread environmental destruction.

What’s So Sustainable About Cork?

Across Portugal, Southern France, Spain, Italy, Tunisia, Morocco, Algeria, and Turkey are swathes of ancient cork oak forest.  These forests are home to endangered and rare species.  These include the Short-Toed Eagle, the Egyptian Mongoose, the Barbary deer, and the Iberian Lynx.  These cork oak forests are also home to biologically important flora and fungi.  And what’s more, the presence of the forest also prevents the soil from drying out and turning into a dust bowl.

You may be wondering how is cork eco-friendly if this is the case?  Well, to extract the cork you may be surprised to hear that not one single tree is cut down.  Instead, the bark of the cork oak trees is peeled away.  The cork is then carefully extracted manually by very highly skilled harvesters.  The trees are in no way damaged and the cork forest in Portugal alone absorbs around 10 million tons of CO2 each year.

Cork is naturally renewable and grows back after nine years.  This system preserves the forest in its pristine entirety.  It also enables perpetual harvesting with no damage to the forest or ecosystem.

natural cork harvest

This ability to renew itself is not the only superpower that cork possesses. Cork is also completely biodegradable.  And from a social point of view cork extraction from oak is also a highly skilled job, in rural areas where jobs are hard to come by.  This skilled work pays very well and helps to support viable rural communities.

The Screw Top Problem

With the widespread infiltration of screw-top wine bottles, the lack of demand for cork means the oak forests are losing their value.  A loss in value means the forests are more likely to be exploited in unsustainable ways.  This threatens the habitat of vulnerable species, threatens livelihoods and threatens the viability of rural communities, and brings the risk of areas turning into dustbowls.  Removal of trees also impacts the ground – meaning flooding is more likely.  So cork is definitely the way forward.

I mentioned I initially thought aluminium screw tops were easily recycled. In fact, it turns out screw tops are not widely recyclable.  More often than not they are too small to be easily recycled. Meanwhile, the plastic stoppers are not recyclable.  On top of this, mining for bauxite (the ore from which aluminium is produced) is one of the most damaging practices on earth.  As such, the increased use of screw tops contributes to this destructive practice.

The plastic seal on the inside of the screw top and the plastic stopper can leach chemicals into the wine, causing taint.  It can also be damaging to human health, which isn’t too great either.

What Can You Do?

What can you do?  Well, the good news is it’s not difficult to help. Just always try and buy wine with a cork in it!  For me, it’s a good excuse to drink Prosecco as generally it is always stoppered with a natural cork!  So you can sit there, with a nice glass of sparkling wine, knowing that you are helping to preserve the forest. And at the same time saving the habitat of the lynx, mongoose, eagle, and host of animals, as well as providing precious jobs in rural areas.

If you’re not buying Prosecco or Champagne It can be difficult to tell if wine is stoppered with natural cork due to the foil covering.  If in doubt shop at a quality wine merchant and ask.  The staff in these places are very knowledgeable about wine and will be able to direct you to natural cork stoppered wines.  100% Cork also has a handy list of wineries that support natural cork stoppers.  You can also look for the FSC (Forest Stewardship Certification) symbol on wine labels.   There’s also a 100% Cork Facebook page which you can join to show your support.

My Wine Might Be Corked

If you’re worried about your wine being corked due the use of a natural stopper, then read on. The primary cause of cork taint is the presence of the chemical compound 2,4,6-trichloroanisole (TCA). TCA isn’t just found in cork. It’s also found naturally in wood, water, soil, fruit and vegetables. This means that myriad other factors, including the storage of wine in wooden barrels, can contribute to wine spoilage.

Over the last 20 years, wine producers have invested in new equipment and worked to refine production techniques. This has contributed to a sharp decline in tainted wine. Recent tests by the Cork Quality Council show a 95% reduction in TCA detection tests.

It’s also important to note that the move to plastic and screw-top bottles was not to prevent corkage.  It was actually for financial reasons.  Screw-tops are cheaper to produce than paying highly skilled harvesters to source cork.  So fear not about your precious wine!

Let’s all raise a glass to this sustainability superhero!

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