In this day of tetra-paks, mylar bags, even thinner glass for bottles, let’s look at the original environmentally friendly wine accessory – the cork. A lot has been said in recent years about cork closures for wine bottles and sometime strong feeling are evoked. People have heard that cork is endangered, that it causes TCA (trichloroanisole, cork taint), that harvesting cork kills trees.
I recently had the opportunity to talk with Patrick Spenser, Director of the Cork Forest Conservation Alliance, a non-profit group based in Oregon dedicated to the preservation and protection of cork forests. In Boston we have the Arnold Arboretum with a speciman Quercus Suber – Cork Oak. I was always fascinated by it. This was an opportunity to dig in and learn more.
The cork oak grows only in seven Mediterranean countries – Portugal, Italy, Spain, France, Algeria, Morocco, and Tunisia. Over 300,000 tons are harvested (stripped) per year. Harvest takes place in the late spring through early summer. Over 60% of all harvested cork comes from Portugal. Over 100,000 people are employed in cork harvesting. Some entire communities in Africa derive a sustainable annual income from the cork harvest.
Important things to know about cork:
- Cork is a sustainable product that is both renewable and recyclable
- It is the bark of the tree that is stripped (harvested) for use as bottle closures (70%), flooring and insulation products, as well as convertion into energy
- Cork trees are never cut down
- They live more than 200 years
- It takes 25 years for a new tree to see its first harvest
- Cork is the only tree that regenerates stripped bark
- It takes 9-12 years for stripped back to be ready for harvest again
The first two harvests of a new cork oak are not suitable for use as a bottle closure. These harvests provide cork primarily for the building trade. It is desireable for its compressibility, insulation and fireproof properties, as well as its resistance to abrasion.
As for TCA, or cork taint as it is known, present in noticable levels in a bottle of wine imparts a musty odor somewhat like wet cardboard or paper. It is not harmful but does ruin the wine. It occurs in less than 1% of wines with cork closure.
Cork trees stripped of their bark absorb and store enormous amounts of CO2, give off more O2, and protect the great biodiversity that inhabit their forests. According to the World Wildlife Fund:
Cork oak forests support one of the highest levels of biodiversity among forest habitats, as well as the highest diversity of plants found anywhere in the world.
In cork oak landscapes, plant diversity can reach 135 species every square metre; many have aromatic, culinary, or medicinal value.
The Cork Forest Conservation Alliance wants you to know that 24x more greenhouse gasses are emitted, and 10x more energy is spent to make just one screwcap wine bottle closure. Synthetic closures are made primarily from petro chemicals, are not biodegradable, and are rarely recycled. Cork trees are not endangered. They live long, protected lives and are nurtured in many places by generations of the same families.
While I have no personal beef with the artificial closure or screwcap manufacturers beyond their increased carbon footprint I hope you will see more than the romance of popping a cork in your continued support of wines that use the cork closure. We can all feel good about supporting such a sustainable product, don’t you think?