Over the Thanksgiving weekend, odds are that you watched a perfect red cylinder of cranberry sauce wobble itself out of a can into a bowl. Or maybe you shook a bunch of mushy peas from a can into a pot. It seems simple enough today, but generations of technological innovation went into making that canned food accessible to you. The grime-covered can opener you fish out of a drawer on holiday weekends is the result of decades of engineering—and a lot of cut-up fingers.
Birth of the can
One of the oddest things about the can opener is that the can predates it by almost 150 years. Though common today, cans were once military-grade technology. In 1795, Napoleon, to whom the phrase "an army marches on its stomach" is attributed, offered 12,000 francs to anyone who could find a way to preserve food. Without any knowledge of bacteria or their role in food spoilage, scientists didn't even know where to begin. It took 15 years before a chef named Nicholas Appert claimed the prize after successfully jarring food. Soon after that, his countryman Philippe de Girard came up with a variant on Appert's method—metal tins—and sold the idea to the British.
Spoiled food, and the sickness it caused, was a widespread problem. The public would have benefited from canned food, but for decades cans were almost exclusively for the army and the navy. The canning process, with its hours of boiling and steaming, its scrupulous cleanliness, its heated metal, and its need for a great deal of disposable material, made canned food far too expensive for anyone but the military. No can openers were needed or even possible. The metal of early cans was too thick to make openers practical. Soldiers and sailors had plenty of sharp objects on hand and made ample use of them when they wanted to eat.