The history of canning

Canning preserves food by sealing it in a container and heating it to destroy the microorganisms that cause spoilage. It has been around since the early 1800s, and it began with an army that needed feeding.

A prize for preserving food

Before canning, food for long journeys was dried, salted, smoked or pickled, and armies and navies struggled to keep soldiers and sailors fed and healthy. In 1795, the French government, then the Directory, offered a prize of 12,000 francs for a better way to preserve food for its troops. The story is usually told with Napoleon, who was soon to take power and is credited with saying that an army marches on its stomach, but the prize was a government one.

The winner was Nicolas Appert, a Paris confectioner who spent some 14 years experimenting. He packed food into thick glass bottles, much like champagne bottles, sealed them with cork and wax, and heated them in boiling water. The food kept for months. Appert received the prize and, as a condition of it, published his method in 1810.

Nobody yet knew why it worked. That came in the 1860s, when Louis Pasteur showed that microorganisms cause food to spoil, and that heat destroys them.

From glass bottles to tin cans

Glass was heavy and broke easily. In 1810, the same year Appert published his book, the English merchant Peter Durand was granted a British patent for preserving food in vessels of glass, pottery, tin or other metals. Durand sold the patent in 1812 to Bryan Donkin and John Hall, who set up a canning business in London and were supplying canned food to the British forces by 1813. The first cans were made by hand from tin-plated iron, a tinsmith producing only about six an hour.

Canned food reached the United States within a few years, and machines gradually sped up production. By the 1840s a worker could make around sixty cans an hour, and in 1849 Henry Evans patented a press that formed can ends in a single operation.

The can opener came later

The first cans were made of thick iron and were opened with a hammer and chisel, often following the maker's own instructions. As cans became thinner and more common, a simpler tool made sense: in the United States, Ezra Warner patented one of the first can openers in 1858, almost half a century after Durand's patent. The rotating-wheel opener familiar today followed decades later.

The Mason jar brings canning home

Home canning took off with a jar. On November 30, 1858, John Landis Mason, an American tinsmith, patented a glass jar with a screw thread molded into its neck and a matching metal lid, which made a reliable seal possible in an ordinary kitchen. When his patent expired, many companies began making "Mason jars," and the name stuck to any jar of that type.

Later improvements, such as the two-piece lid with a sealing compound and research-tested processing times, made home canning safer. Home canning surged during both World Wars, when governments urged families to grow and preserve their own food, and it remains a way to keep the taste of a summer harvest all year.

Today, canned food is everywhere, from tuna and tomatoes to Spam, introduced in 1937. Learn more about how canning works, or start with our introduction to canning.