Meats, vegetables, seafood, fruits—almost anything edible has a canned version. We are used to having a collection of canned foods on hand, ready for when we want to prepare a particular recipe. Despite their ubiquity, not everyone knows that they are an invention of the Frenchman Nicolas Appert, who perfected this mechanism more than 200 years ago.
The Problem: War, Hunger, and Scurvy
They are part of our culture. Although we don't think about it, almost every day we consume some food that has been processed and stored inside a can before reaching our table. It is a safe mechanism that allows food to last intact for years, applicable to almost anything edible. The credit for such a useful invention is attributed to a French researcher named Nicolas Appert, who, more than 200 years ago, embarked on the search for a system that would allow the military of the time to have more or less decent and safe rations.
At that time, France was at war, and although from a military point of view results were obtained (that is, they were more efficient at killing people than their enemies), the truth is that both civilians and soldiers responsible for keeping the war machine running died like flies, victims of hunger, scurvy and other diseases associated with eating spoiled food.
In this scenario, it became essential to find a way for people to have food in good condition, replacing the junk they were forced to eat. The country's government decided to take the bull by the horns, offering a reward - 12,000 francs - to anyone who could provide an effective system to not only preserve food but also facilitate its transport and distribution at the front and in attacked towns.
Appert's Breakthrough
Appert worked on the problem, and although he (nor anyone else at the time) had absolutely no idea of the causes that caused the decomposition of roast meat or bread, he managed to solve the problem. During his experiments he noticed that those foods that were heated inside an airtight container, free from the action of air, were able to remain in good condition for months. Despite not knowing the existence of bacteria responsible for decomposition, he was able to deduce that cleanliness and hygiene during preparation, as well as the hermetic sealing of containers, were essential for proper preservation.
Since making an airtight metal container was beyond his possibilities, Appert used glass bottles sealed with cork. These containers were boiled in vats, allowing the heat—although the researcher did not know it—to kill the germs that were inside. The foods thus prepared were distributed among the ranks of the French navy, and Napoleon Bonaparte himself publicly supported Appert's invention.
The Prize and the Book
The 12,000 francs prize was given to him, and he published a book titled “El libro de todos los hogares. El arte de preservar sustancias vegetales y animales por muchos años”, in which he explained his method in detail. As often happens, some historians attribute the invention of the method of sterilizing food by heat to another person—Lázaro Spallanzani in this case—but the latter carried out his work half a century later.
The Spread of Canning
Appert's book became a success, and as is well known, his system began to be used massively in peacetime. The same year his discoverer published the book explaining how to preserve about 50 different foods, an English merchant named Peter Durand requested from King George a patent to commercialize products prepared in this way. The cans began to be used when Durand transferred (for a nice sum of money) the rights of his patent to Byan Donkin and John Hall, who owned the iron foundry Dartforl.
These Englishmen made—among other things—iron cans covered with tin. At that time, they sent the first cans of food to the army and navy of their country, who after “experimenting” with the troops stationed in the garrisons of Saint Helena and the Western Islands determined that they were perfectly suitable to replace glass containers, while providing their contents with a more resistant “wrapping”. From that moment on, every expedition that left for distant lands—such as the Arctic—was provided with its corresponding load of canned food.
Understanding the Science
It was not until Pasteur's work that humanity learned that food spoilage was caused by the action of microorganisms. Today, as we said at the beginning, we can find the most diverse foods preserved in a can. We have them thanks to the effort of Appert, who was able to deduce—even without a solid scientific basis to support his investigations—how to prepare them.
