The ubiquitous can has come a long way since 1795 when Napoleon offered a 12,000-franc prize to anyone who came up with a food preservation method that would assure his men had safe rations. Parisian confectioner Nicolas Appert claimed that prize by driving out air and heat from food in a glass jar before sealing it. While he’s widely regarded as the father of food preservation, canning really took off after the invention of the more practical and durable metal can in 1810, when English merchant Peter Durand got the first patent for a tin-plated container.
Nowadays, Americans use more than 100 million metal cans a day in 600 different sizes and styles. Of the 131 billion metal cans produced each year, some 26 billion are used for food preservation, according to the Can Manufacturers Institute. Scientists in the U.K. recently ranked canning among the Top 20 food and drink innovations of all time just behind refrigeration and pasteurization/sterilization, according to the Daily Mail newspaper.
In fact, canned foods help with food safety, as stated by a May 2012 Michigan State University study that analyzed more than 40 scientific journal studies comparing canned fruits and vegetables to fresh and frozen. “Depending on the commodity, freezing and canning processes may preserve nutrient value, and while canned foods are often regarded as less nutritious than fresh or frozen products, research reveals that this is not always true,” Michigan State University authors Steven Miller, visiting instructor, and Bill Knudson, professor, concluded. The study also stated that canned foods are the safest form of food because of barriers to microbiological contamination generated during the canning process.
At the time of Durand’s and Appert’s inventions, food safety was literally a life and death proposition. That’s because the initial use of canning was for soldiers in the field. Glass jars were fragile, but metal cans presented their own challenges. Because the can opener wasn’t invented until 1855, soldiers opened early cans with bayonets or smashed them with rocks.
The first Durand patent granted by King George III of England in 1810, and which was re-filed in the U.S. in 1818, was for a method of preserving animal, vegetable, and other perishable foods using vessels made of glass, pottery, tin, and other metals, though Durand focused only on the tin can to improve on Appert’s glass storage. The procedure involved filling a can with food, raw for vegetables and half-cooked or raw for meats, and capping it. The filled can could then be heated in an oven, stove, or steam bath, or immersed in water and then boiled. During the heating and subsequent cooling procedure, the cap was left partly open, but immediately afterward it was sealed airtight by a cork, screw cap with a rubber seal, or a cemented cap.
Durand does acknowledge in his first patent that he got the idea for the invention more than a year earlier from a friend abroad, who is thought to have been French engineer and inventor of the first flax spinning frame, Philippe de Girard. The Frenchman demonstrated canned foods at the Royal Society in London. Durand’s patent describes both the original idea and observations by Durand, who tested the concept thoroughly by sealing meat, soups, and milk and boiling them using the method. The original inventor had tested only small volumes of food, but Durand had expected large-scale production in the future and preserved up to 30 pounds of meat in one can. He also tested the canned goods with the Royal Navy for four to six months, and reports by members of the Royal Society and Royal Institution said the food was preserved.