It is an amazing fact that such a war-necessary tool as a can opener for opening tin cans was created almost 50 years after the release of these canned goods.
The reason for the appearance of a can opener
In 1795, before Napoleon’s campaign in Europe with the aim of conquering it, the French government faced the task of finding a rational way to preserve food for a long time. A reward of 12,000 francs was promised for a worthy offer. The prize went to the cook Francois Upper, who proved that a finished product, such as fried meat, which is in an airtight container and boiled in water, can be kept closed for at least a year. Glass containers were offered to them as containers. And in 1809 they began to produce the first products in the form of conservation.
Due to fragility, glass jars were replaced with tin containers a year later. The patent for the use of tin received the Englishman Peter Durand. Although iron cans were more reliable, but due to the thickness of the tin of 5 mm, they weighed more than the product contained in them. In addition, it was necessary to make a lot of efforts to open canned food. A hammer and a chisel were required for opening.
The invention of a can opener
48 years before the contents of canned goods were reached by all means at hand, until Ezra Warner came up with the idea of creating a product with which it would be easy to open a tin can lid. The patented can opener had two blades, one had to pierce the can, and the other put the knife on its side. The invention, as well as canned food, gained popularity only during the Civil War, when soldiers were given canned food, and a Warner knife was attached to it.
In the future, there was widespread interest in creating a product simpler and easier to use. J. Osterhud in 1866 received a patent for a tin can, on the lid of which had a key. With each turn, its cover twisted, 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, having on one part a knife in the form of a wheel. The principle of opening the can is also similar to the operation of the compass. One pointed leg stuck into the center of the round lid, and another leg with a wheel moved along its circumference, which opened the can.
In 1921, Lyman's can opener was slightly improved. On the outside of it, where the cutting wheel was located, a guide gear was installed. The rim of the canned food was located between the wheels, which did not allow the knife to slip.
Modern can openers
In 1942, the Chicago-based laboratory for life support invented the easiest-to-use can opener R-38. In order to open a tin can, it was necessary to press and lift the key 38 times, while tremendous pressure developed on the lid. The key was stamped literally in seconds and consisted of two folding parts. The knife was attached to the army ration. After use, the can opener should be washed in boiling water to get rid of the remains of the contents of the can.
Later, electric knives were invented, opening canned food in seconds. Moreover, the can is held between the knife and the gear and does not fall.
Opening technique
To date, the most affordable can opener has a metal or wood handle and an iron plate with two horns of different sizes. With its help, you can open not only canned goods, but also beer bottles, pastes, stew and grandmother's marinades. The process is not complicated, and yet 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 strike with your hand, applying force, on the handle, punching tin. The horn should plunge into the jar, after which you need to advance the knife around the circumference, swinging it up and down, but not pull it out.
To open a bottle of beer, place the edge of the lid between the horns, place a long one on top and pull the knife up, while slightly pushing the opener onto the bottle lid.
Care for can openers
A can opener can cause food poisoning. If it is not washed, numerous food debris from various products accumulate on the blade. You can imagine how toxic the unwashed tool is. Taken scrapings from can openers in the study showed the presence of various pathogens of diseases and infections. To avoid infection, it is necessary to rinse the blade with boiling water every time after opening the can. Cleaning a can opener is easy. You can wash it in your hands or put it in the dishwasher. Aged dirt is well brushed off with a toothbrush.