The Invention of Canned Food

Before the nineteenth century, keeping food fresh for long periods was a serious problem, especially for armies and sailors who spent months far from farms and markets. In 1795, the French government offered a large prize to anyone who could find a better way to preserve food. The winner, announced in 1810, was Nicolas Appert, a cook and candy maker from Paris.

Appert's method was simple. He placed food in glass bottles, sealed them tightly with corks and wax, and then heated the bottles in boiling water. Food prepared this way stayed safe to eat for months. Appert himself could not fully explain why his method worked. It was not until the 1860s that Louis Pasteur showed that food spoils because of tiny living organisms, which are killed by heat and cannot enter a well-sealed container.

Glass bottles, however, were heavy and broke easily. In the same year that Appert won his prize, a patent was granted in Britain for using metal cans instead. Early cans were so thick that they had to be opened with a hammer and chisel, and the can opener was not invented until several decades later. Nevertheless, canned food soon became essential for long sea voyages and military campaigns.