Portugal pops a cork to the regeneration of a formerly ailing industry – and to its sustainable future

Every summer, in the southern Alentejo region of Portugal, workers armed with razor sharp axes spend their days carefully harvesting cork trees. The work, which is highly skilled and has used the same methods for hundreds of years, is entirely manual, and involves diligently separating the outer and inner bark, before drying and processing the planks. A single cork tree can live for more than 200 years and during that time it can be harvested once every nine years after the age of 25.

Until a few years ago, Portugal’s centuries-old cork industry was in decline; fears over occurrences of ‘cork taint’ spoiling the taste of wine led to a surge in the popularity of bottle stoppers made out of synthetic materials, glass and metal. Wine stoppers account for 70 per cent of Portugal’s cork exports, and while around 40 million cork stoppers are made daily in Portugal, demand for cork – which is sustainable, recyclable and biodegradable – has expanded well beyond the wine industry.

Portugal produces an estimated 100,000 tonnes of cork annually and it is now used for everything from a vegan alternative to leather to a natural option for flooring. Responsible for 63 per cent of global cork output, equivalent to approximately €986.3 million, industry advocates also highlight the fact that the sector provides decent, green, skilled jobs for thousands of workers, setting an example for other industries as the world transitions to its low carbon future.

In Portugal, Corticeira Amorim – the world’s biggest producer of cork products – is currently developing solutions to build an entire house of cork through a modular construction system. Cork has also been used by Mercedes-Benz to make an eco-friendly car prototype, with everything from the dashboard to the steering wheel lined with the material. Cork is also used in construction, in expansion joints, cold stores, heating and air conditioning pipes, and machinery bases.

Cork’s energy efficiency is ever more pertinent as the world scrambles to cool rising temperatures caused by greenhouse gas emissions. Additionally, cork is the only tree that can have its bark removed without killing it, which allows for repeat harvesting.

At Portugal’s University of Aveiro, researcher Rui Novais from and his team are developing new applications for cork - particularly in the construction industry. One of their focuses is an ecologically friendly cement that contains cork to be used as an alternative to traditional thermal insulating materials. His team has also been looking into producing renewable fuels through cork-based ceramics, used as a catalyst to separate carbon dioxide with concentrated sunlight.

“We have been focusing on materials in the context of the circular economy,” Novais tells Equal Times. “There has to be a paradigm shift. Cork is extracted every ten years through a natural process. The tree is not damaged, and its ability to absorb CO2 makes it doubly advantageous.”

Amongst other things, Novais and his team have found that by adding cork to eco-cements, they can effectively shield buildings with a material that provides good thermal acoustic insulation. “There are two different applications: to shied buildings against electromagnetic radiation pollution we need to add pyrolyzed cork in small quantities, while to have thermal and acoustic insulators we use cork [without any pre-treatment] in high volumes,” Novais explains.

Sustainable forest management

Amidst a growing interest in sustainability, significant investment has enabled the development of new and unexpected uses of cork. But the industry is also faced with a challenge: ensuring that Portugal’s 736,000 hectares of cork oak forests are better managed.

“Sustainable forest management is so important,” says Angela Morgado, executive director at Associação Natureza Portugal (Portugal Nature Association, or ANP), a non-profit Portuguese NGO dedicated to the conservation of nature and the protection of the planet, in partnership with the World Wide Fund for Nature (WWF). “The better managed it is, the higher its conservation, and we know that it provides so many important environmental benefits like retaining carbon dioxide and regulating soil.”

As climate change drives increasingly longer dry periods, cork forests are an important way to avoid forest fires like the deadly Pedrógão Grande wildfires in 2017. As early as 2006, the WWF warned in a report titled Cork Screwed? that the future of 2.7 million hectares of cork oat forests in Portugal, Spain, Algeria, Morocco, Italy, Tunisia and France were at risk of desertification and forest fires if (the then) predicted decline in the cork stoppers market led to the conversion of lands to other, environmentally damaging uses.

Today, the Green Heart of Cork project, spearheaded by WWF/ANP, aims to conserve the world’s largest area of cork oak forests – in the lower valley of the Tejo (or Tagus) and Sado river basins – by compensating landowners who contribute towards good farming and forest practices. “The fact that cork oak forests are semi-natural implies that they have to be managed, or else it is probable that it will evolve towards another kind of system,” explains Rui Barreira, director of conservation at WWF/ANP.

Portugal is badly affected by desertification, in part due to its dry climate, and cork trees act as an important safeguard. When well-managed, cork forests create greater biodiversity, improve soil’s organic material and contribute to the regulation of the hydrological cycle. Portugal’s national School of Agronomy (ISA) estimates that cork oak forests can fixate around 6 tonnes of CO2 per hectare – which in Portugal translates to over 4 million hectares per year. For this reason, the cork tree is considered a ‘priority species’ by the WWF/ANP in the fight against desertification and climate change.

Decent, green jobs

Although cork is harvested by hand using ancient techniques, technology is playing an increasingly large role in the industry, with companies like Corticeira Amorim investing heavily in innovation, for instance, in quality control screening technology called NDtech to root out TCA, one of the chemical compounds considered responsible for cork taint.

The cork industry also provides direct jobs for approximately 12,000 to 14,000 workers in Portugal, in addition to 6,500 jobs in forest extraction and thousands more indirect jobs, according to the WWF/ANP. Cork strippers are known as tiradors, and although they work is short-term and seasonal (harvest usually takes place between June and July) they are typically paid a day rate of between €80 and €120, which is a good wage in rural Portugal. Most tiradors also receive health care and other benefits.

The introduction of new technology is also helping to create new graduate-level roles. According to a 2018 article by Forbes, Corticeira Amorim’s NDtech has created jobs for a new generation of educated workers, and more than 700 new jobs in total.

Even in admin positions, cork industry jobs tend to be above average in terms of remuneration and working conditions, according to the Portuguese trade union SINDCES. “It is a dynamic sector because it is focused on exports and it is adapting to new products that go beyond the wine industry, such as the construction industry, for instance,” says Pedro Barqueiro from SINDCES.

Portugal’s main cork association APCOR is optimistic regarding the future of cork. In a written statement to Equal Times it said the sector had seen an average wage increase of 2.4 per cent in the last year. APCOR also said: “In the past years, the cork industry has registered an average yearly increase of 4.5 per cent having reached a value of €1 billion in 2018. That value increased slightly in 2019, standing at €1.064 billion. These figures allow us to look towards the future with enthusiasm and optimism.”