At the beginning of the 19th century, a Frenchman by the name of Nicolas Appert invented the method of preserving food in closed containers. Later, an Englishman, Peter Durand, developed the idea, filing a patent for a metal casing.
That same century, Portugal saw its first fish canning factories. The proximity of the coast and the length of coastline, combined with the abundance of high-quality fish, created the natural conditions for the development of the canning industry, and Portugal even became at one time the largest producer in the world.
In the 20th century, World War I proved to be the great opportunity for the Portuguese canning industry. As Portugal was not involved in the hostilities directly, Portuguese preserves fed soldiers on both sides of the conflict and the industry thrived. History repeated itself in World War II, but in the post-war period the sector lost its main target markets and the sales slump was inevitable; of the 152 factories that existed at the time, there are two dozen left.