Can opener is an invention with a 150-year experience

The surprising fact is that such a tool necessary in wartime, like a can opener for opening cans, was created almost 50 years after the release of these cans.

The reason for the appearance of a can opener

In 1795, before the campaign of Napoleon to Europe with a view to its conquest, the French government was faced with the task of finding a rational way of preserving products for a long time. A reward of 12,000 francs was promised for a worthy offer. The prize went to the chef François Appper, who proved that the finished product, for example such as roast meat, which is in a sealed container and boiled in water, can be kept closed for at least a year. As a container they were offered cans of glass. And in 1809 they began to produce the first products in the form of conservation.

Because of the fragility, glass jars were replaced in a year with tin cans. The patent for the application of tin was received by the Englishman Peter Durand. Although there were iron cans more reliable, but due to the thickness of a sheet of 5 mm they weighed more than the product contained in them. In addition, it was necessary to make a lot of effort to open canned food. For the opening, you needed a hammer and chisel.

The invention of a knife for opening canned food

48 years before the contents of canned food got all the improvised ways, until I came to Ezra Warner idea of creating a product with which you could easily open a tin can. The patented can opener had two blades, one needed to pierce the jar, and the other to rest the knife in its edge. The invention, as well as canned goods, gained popularity only during the Civil War, when soldiers were given food in canned form, and a Warner knife was attached to it.

Later, there was a wide interest in the creation of a product that was simpler and easier to use. J. Osterhood in 1866 received a patent for a tin can, on the lid of which there was a key. With each turn his lid curled, more and more opening access to the contents.

A can opener with a wheel was invented in 1878 by William Lyman. The knife resembled a drawing compass, which has a knife in the form of a wheel on one part. The principle of opening a can is similar to that of a compass. One pointed foot stuck into the center of the round lid, and along its circumference another leg with a wheel that moved forward opened the jar.

In 1921, Lyman's can opener was slightly improved. On the outer side of it, where the cutting wheel was located, installed a guide gear. The can of canned food was located between the wheels, which prevented the knife from slipping.

Modern canning knives

In 1942, the Chicago laboratory, which investigated the provision of life, invented the easiest-used can opener P-38. In order to open the tin can, it was necessary to press and raise the key 38 times, while developing colossal pressure on the lid. Stamped the key in just seconds and consisted of two folding parts. A knife was attached to the army ration. After use, the can opener should be rinsed in boiling water to get rid of the remaining contents of the can.

Later, electric knives were invented, opening cans in seconds. Moreover, the bank is held between the knife and the gear and does not fall.

Opening technique

To date, the most affordable can opener has a handle made of metal or wood and an iron plate with two horns of different sizes. With its help you can open not only canned food, but also beer bottles, pates, stews and grandmother's marinades. The process is not complicated, but nevertheless there are those who are wondering how to use a can opener. First of all, you need to install a long horn at the edge of the can and hit with your hand, applying force, on the handle, punching tin. The horn should be immersed in the jar, after that it is necessary to move the knife along the circumference, swinging it up and down, but not pulling it out.

To open a bottle of beer, you should place the edge of the lid between the horns, with the top placed long, and pull the knife up, while lightly pressing the bottle opener on the lid.

Care of canning knives

Can opener can provoke food poisoning. If it is not washed, numerous remnants of food from various products accumulate on the blade. You can imagine how poisonous the dirty instrument is. Taken scrapings with canning knives on the study showed the presence of various pathogens of diseases and infections. To avoid infection, it is necessary to wash the blade with boiling water every time after opening the can. Cleaning a can opener is not difficult. You can wash your hands or put it in the dishwasher. The old dirt is well cleaned with a brush for teeth.