Canning

a process of preserving perishable articles of food by excluding agents of decay. The article to be preserved is first heated to sterilize or kill bacterial germs, and is sealed up in sterilized, air-tight glass or metal jars to keep bacteria out. If bacteria within be killed and bacteria without be kept out,--that is, if sterilization and sealing are successful, canned goods keep fresh indefinitely. The process was invented, or rather discovered, in France about the beginning of the nineteenth century, so that no tests of ancient canning are possible; but canned goods sealed up over eighty years ago are still palatable.

Housewives not infrequently seal earthen jars with sheets of writing paper, rendered air tight by a sizing of the white of an egg; but glass jars with metal covers are more convenient and are safer. The jars are usually surrounded by boiling water and filled with boiling hot fruit, the covers are screwed on tight, and the process is complete. If all be done with care and neatness, the jars may be set away for years without reason to fear fermentation.

The process in large canning establishments is essentially the same. Tin cans are set in hot water, and are filled with boiling hot fruit, vegetables, or fish. The orifice is covered with a piece of tin, which is sealed in place with a soldering iron. An awl hole is left open; the contents of the can are brought to a boil. The hole is then sealed with a drop of solder. If bacteria are excluded successfully, the goods cannot spoil.

The canning industry in America appears to have begun in New York City about 1818 with lobster and salmon; but it has been extended to include all kinds of meats, fowl and fish, vegetables, soups, milk, fruits, not to name a large number of pickles and relishes. Canned goods grew in favor slowly until about 1850, when the rush to the gold fields of California, followed by the Civil War and the opening of the Great Plains and Rocky Mountain regions, created a tremendous demand for all sorts of canned food.

"Thirty years ago," says the California Fruit Grower, "canned goods were a luxury, relatively expensive, and used only in emergencies, on shipboard, or at remote places where other food was unobtainable. Today their use is universal among the poor as well as the rich. It would be difficult to find a home, hospital, club, hotel, steamer, or buffet car without its assortment of them."

The last United States census gives the value of pickles, fruit, and vegetables put up in cans at $78,175,359. The annual number of cans, almost incredible until the reader pauses to recall how omnipresent canned goods are in every grocery, is given by the same authority as: peas, two-pound cans, 65,718,024; corn, two-pound cans, 152,783,208; tomatoes, three-pound cans, 213,739,992; and other vegetables, as string beans, pumpkin, beets, squash, asparagus, etc., in great quantities.

Canning is carried on in every province, state, and territory of North America, but shows a tendency to centralize. California leads easily in fruit. The state put up 3,283,296 cases of fruit in 1905. Maryland cans a good fourth of the tomatoes and peas. New York still leads in canned corn, but Illinois and Iowa are in close pursuit.

See Salmon; Oysters; Bacterium