We tend to take cylinders for granted. Cans of food line grocery store shelves. They fill our cupboards and our soda machines. We collect them for food banks and take them camping. We forget that the metal can has actually saved countless lives.
Can You Prevent Food Poisoning?
Before the practice of canning became widespread, food poisoning took many lives. In a world without refrigeration, soldiers and sailors often ate spoiled food. Their deaths were quick and agonizing. At the turn of the 19th century, Napoleon, the emperor of France, demanded a solution. He knew that if his army had reliable food, it could conquer the world. In the late 1790s, a French scientist found a way to preserve food in glass jars. This discovery made a huge difference in the lives of the military, but there was a major problem: glass jars broke easily during shipping.
By 1810, the English began using tin cans instead. The early cans were expensive as each can had to be made by hand. It took a worker all day to make just four cans of food. Still, the cans proved vital to soldiers, sailors, and explorers. A man could go anywhere if he could carry his food with him—even into the jungle or up to the Arctic.
Today, our cans are made in factories, sometimes called canneries. Typical soda cans are made from just two pieces of metal: a base and a cap. Machines form the base from a single circle of aluminum. They shape it into a cup and stretch it. They trim it, coat it, and paint it. Finally, they form the bottom into a dome. This shape helps the can remain strong while using a minimal amount of metal.
See for yourself: http://www.youtube.com/watch?v=JyumWUg_MXM
Learn more about the history and process of canning food by watching the videos below.