Cork Factory Tour

When Shana told me that we were going on a tour of a cork factory during our trip to the south of Portugal, I assumed that the factory produced corks (i.e., what the people in the cork industry call wine stoppers). But, it turned out that the factory we toured literally makes the "first cut" of cork, which is then sold to companies that may use it for wine stoppers or other products depending on its age and quality.

Raw cork is basically the bark of a cork tree. When a new cork tree is planted, the planters know that it will not provide any cork for about 25 years. After 25 years, the first cork taken from a tree is know as virgin cork, and it is only useful for things like cork board or panels used to soundproof rooms. It cannot be used for wine stoppers. After that, cork trees are harvested about every nine years, but the second harvesting also can only be used for the same purposes as the first. So, when the third harvesting comes around, which is at least 43 years after the tree is planted (it can be as long as 50 years), you have raw cork that is usable for wine stoppers. The raw cork looks like this:

After the raw cork arrives at the factory it is boiled in a large copper vat using a wood fire (nothing is added to the water). This process serves to make the cork more pliable and usable. Next, a highly-trained worker looks at each piece of cork, cuts away parts that cannot be used for wine stoppers (there are a number of reasons this might be the case including holes in the cork made by bugs, and algae), and separates the cork by thickness. This worker has been doing that job for 43 years, having started when he was 13:

As our guide showed us, this process allows the cork to be stacked by thickness, which allows buyers to come to the factory and select the cork they need. A close-up-look also shows horizontal lines in the cork, like rings in trees, indicating the growth process:

That is literally the entire process undertaken by the factory we visited. Nonetheless, we learned a lot about wine stoppers including the difference between a natural cork wine stopper, which has small holes allowing some air to enter/exit, and composite stoppers, which are used for sparkling wine, so that the fizz does not escape.

The cork tree is the national tree of Portugal and the tree has been protected there since the 13th century due to its importance to the country's economy. Portugal produces 50% of the world's cork supply. Spain produces most of the rest.  As you can see, it was a really interesting tour.

More to come from Portugal soon.

Jeff and Shana