You might not realize it, but the humble cans of soup gathering dust in your pantry helped revolutionize the world. And believe it or not, canned food actually started as a weapon of war.
Canning was invented in 1809 by Nicolas Appert in response to a request by the French army to create a method for preserving foods for a long period of time. Large armies require lots of food, especially if they are deployed for extended periods. And if armies are operating far from their home territory, securing supplies and food in particular can be difficult. Canning made it far easier to preserve food. This, in turn, made it easier to supply armies, explorers, and others who had to rely on preserved foods.
While Appert invented the canning process, he didn’t actually understand why it worked. It would take another half a century for Louis Pasteur to unwind the mysteries of canning. When food is canned, it is placed in a can or similar container, such as a glass jar. The container is then sealed, which prevents outside organisms from getting in. Next, the canned food is heated to kill off any germs still alive inside. Pasteur was the first to prove that microbes caused food to spoil.
Ultimately, canned foods made it easier for explorers to travel through the American West and to cross oceans the world over. For better or worse, canned foods also made it easier to deploy large armies for longer periods of time. This may have made the American Civil War and Crimean War in Europe, among other conflicts, bloodier as armies were able to march farther and stay in the field longer.
By the early 1900s, canning food was a popular home technology, adopted by women worldwide after the invention of new sealable jars by Charles Ball and Alexander Kerr.
Canned foods also help make food in general cheaper. Up until the 20th century, food took up a much larger portion of the average family’s budget.