Today and tomorrow we’ll be taking a look at another essential item in the home food preserver’s arsenal – canning jars. Today we’ll check out the history of the venerable mason jar. Tomorrow we’ll investigate the nuts and bolts of selecting the right jar for the use you have in mind.
In the Beginning
Nicholas Appert is revered as the Father of Canning. He was a French candy maker who responded to Napoleon’s call to devise a means of keeping food safe to eat for his armies on the move. Appert set to work and won the challenge. The army had their food and Appert had his place in history secured.
In 1858, a 26-year old tinsmith from New York City, John L. Mason, invented a machine that could cut threads into lids, which made it practical to manufacture a jar with a reusable, screw-on lid. He recorded his invention as "Mason’s Patent Nov. 30th. 1858” and the Mason jar became the foundation upon which the home canning industry was built, although manufacture really didn't take off until after the Civil War.
Jars as Collectibles
Many of us have inherited canning jars or purchased these treasures in old cardboard boxes at garage sales. Some of these jars are highly collectible, and learning about their history is fascinating. If this hobby interests you, you will need an eye for color.
A purple jar likely predates the First World War. At that time, manufacturers used manganese dioxide to clarify glass, but the element reacted with sunlight, turning the glass purple. During the First World War, the source of manganese dioxide was cut off by German blockades, so selenium became the permanent replacement. Selenium does not cause glass to react to sunlight as manganese does. Knowing this fact can help you date your jar.
Amber jars were designed to prevent canned fruit from turning brown in sunlight. Homemakers complained the contents were difficult to see, so this color was discontinued.
The Kerr Company tried to produce green jars for a customer who wanted that color to show off his olives to best advantage. They couldn’t get the color right. Instead of green, the glass kept coming out a cornflower blue. Blue made the olives a sickly shade of puce and the customer cancelled the order. However, collectors pounced on the jars.
If you've got some old jars, keep them as decorative accents to your kitchen. These jars may be valuable. They also have outlived their lifespan as far as holding up to the rigors of modern day canning practices. If you're interested in learning more, check out the fruit jar collectors group at http://groups.yahoo.com/group/fruitjars/.
Tomorrow: Getting down to business with modern day canning jars.