It's one of the most versatile and sustainable materials in existence, used in products from shoes to the nose cone of spaceships.
Cork has been used for decades to keep wine in bottles. But some key properties, that of being water resistant, flame retardant, flexible, renewable and recyclable means its uses are expanding.
Wine corks made at the Amorim factory. /Ken Browne/CGTN
Cork is harvested from cork oak trees, which are stripped once every nine to 12 years, in a process which does not harm the tree. In fact, a stripped tree will absorb an average five times more carbon dioxide than an unstripped one. Over time, the cork grows back like a layer of skin.
Portugal and neighboring Spain are home to sizable cork forests where the resilient and adaptable trees thrive despite the sandy soil and scarcity of water.
Who is the largest producer of cork?
Despite its small size, Portugal is the largest cork producer in the world, responsible for over 70 percent of all global exports. The trade brings in $1.2 billion a year and provides over 8,500 jobs locally, rising to around 100,000 in the wider Mediterranean region.
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With its tag line "From bark to bottle" the Amorim wine cork factory in the city of Porto is the world's largest producer of cork stoppers. But its dominance was threatened at the turn of the century when Australian and New Zealand wine producers increasingly turned to plastic and screw-top alternatives.
"Australia became a paradise for screw caps," Carlos de Jesus, Amorim's Director of Communications told CGTN Europe. But the country's wine producers began returning to cork tops in the past decade.
De Jesus said the Australians were influenced by China. "China decided that we want our wine with a material that is 100 percent renewable, 100 percent sustainable, 100 percent recyclable, and it makes a lot of sense to be in a bottle of wine. That is the power of the Chinese market."
Cork stacked up at the Granorte factory in Porto. /Ken Browne/CGTN
Some Portuguese cork producers see China as a market with great growth potential.
Granorte is a factory that takes the excess cork leftover from wine stopper manufacturing and turns it into ceiling and floor coverings.
"The cork stopper, after being used to seal a bottle of wine, can come here and we can recycle and turn that small cork stopper into a part of a flooring or a wall covering," Paulo Rocha, Granorte's Technical Manager told CGTN Europe.
"The possibilities of recycling, using and reusing cork, are without limit and this is really one hundred percent sustainability and Chinese people are more and more confident in cork products," he added.
According to Rocha "There are a group of people that wants to be slightly different, that wants to say to their friends that they care, that they use natural, renewable products."
With demand rising in China, many cork proponents say the material is one of the very few that achieves a rare balance between people, planet and profit.
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