Most boiling water canning containers are made of aluminum or
porcelain-covered steel. They have fitted lids and removable
racks that are either perforated or shaped wire racks. The
canner must be deep enough so that at least one inch of briskly
boiling water will be over the tops of jars during processing.
Some boiling water canners do not have completely flat bottoms.
A flat bottom must be used on an electric range. Either a flat
or ridged bottom may be used on a gas burner. To ensure uniform
processing of all jars with an electric range, the canner should
be no more than four inches wider in diameter than the element
on which it is heated. (When centered on the burner or element,
the canner should not extend over the edge of the burner or
element by more than two inches on any side.) This 15 step-by-
step guide teaches the basics about boiling water canning,
including: - Basic preparation - How to clean and sterilize
glass jars. - How to properly storage jars. If you have ever
wanted to learn the basics of