Wednesday, October 11, 1989

The “Tin” Can: A Place in History

The tin can owes its beginnings to several creative individuals who perceived a need, and perhaps a market opportunity, for a container in which food could be stored and shipped while maintaining optimum quality. Initial efforts were directed toward the use of glass containers. While those efforts continued, the use of glass was limited by its inherently fragile
nature. The world needed containers that could be transported across the globe by ship - arriving at their destinations fully intact. Ultimately, Englishmen John Hall, founder of the Dartford Iron Works, and Bryan Donkin, his associate, successfully developed the first commercial use of iron and tin containers for food preservation.

The first trials of their tinned food were undertaken by both the Army and Navy, desperately in need of unspoiled rations offering a relatively high vitamin content. Found to be highly acceptable, the tinned foods were further distributed throughout the English military. Some of the canned foods included seasoned mutton, broiled veal, and vegetable soup.

The preserved foods provided nutrition for travelers throughout the world, even in the far reaches of the Arctic zone. And, from stores left lying in the Arctic and other locations, there was ample evidence of the cans’ ability to preserve the food they contained. In one experiment, foods canned in 1826 were opened 20 years later and found to be perfectly preserved.

In the early 1840’s, several people introduced an improved method of vacuum sealing tin cans by boiling them in various types of chemical baths at 270-280 degrees F., instead of the traditional heating methods with stoves or ovens. One of them, Stephen Goldner, began marketing tinned foods sealed with this process, and by 1847, some of his selections included milk, turtle, and carrots.

The vacuum sealing process continued to be developed. It consisted of placing partially cooked provisions in a tin canister, with a small amount of liquid, and soldering the cover on the container, which was punctured with a small hole. The container was partially immersed in a saline bath heated above the boiling point of water, and left in the bath until the air had been completely expelled. The hole in the canister was then hermetically sealed with solder. As a final test, the sealed container was placed in a room heated to 100 degrees F. This method of testing ensured that the canned foods would stay fresh, regardless of the conditions to which they might be subjected.

These early cans were heavier and of much stouter construction than the modern tin can. For example, a veal can - excluding contents - weighed about seventeen ounces, standing six and one-quarter inches, with a diameter of five and one-quarter inches. Its body thickness was almost one fiftieth of an inch, and it had a tin coating of about one-half of a thousandth of an inch. A modern steel can, of the same height and diameter, would weigh less than seven ounces. Its body thickness, by comparison, would be only eight thousandths of an inch or less, and the tin coating, a mere twelve millionths of an inch or less.

The tinned steel can has come a long way, in design, composition, and production. But the purpose of the can has never changed. It provides one of the most practical, tamper-proof, strongest, and most attractive packages known to mankind, and it will continue to help feed our nation’s citizens - in their homes and on their travels.