Michigan
State University Extension
Preserving
Food Safely - 01600497
10/13/97
Food may be canned in glass jars or metal containers.
Metal containers can be used only once. They require
special sealing equipment and are much more costly than
jars.
Regular and wide-mouth Mason-type, threaded, home-
canning jars with self-sealing lids are the best choice.
They are available in 1/2 pint, pint, 1-1/2 pint, quart and
1/2 gallon sizes. The standard jar mouth opening is about
2-3/8 inches. Wide-mouth jars have openings of about 3
inches, making them more easily filled and emptied. Half-
gallon jars may be used for canning very acid juices.
With careful use and handling, Mason jars may be reused
many times, requiring only new lids each time. When lids
are used properly, jar seals and vacuums are excellent
and jar breakage is rare.
It is recommended that mason-type jars designed for
home canning be used for preserving food by pressure or
boiling-water-bath canning. However, some commercial
pint and quart size mayonnaise or salad dressing jars may be
utilized for canning acid foods in a boiling-water canner
when new 2-piece lids are used. However, you should expect
more seal failures and jar breakage.
Commercial mayonnaise jars are weakened by repeated
contact with metal spoons or knives used in dispensing
mayonnaise. Seemingly insignificant scratches in the glass
jars may cause the jars to crack or break during boiling-
water canning. Commercial jars are not recommended for use
in pressure processing. It is recognized that some people
continue to can products successfully using commercial
mayonnaise jars with new 2-piece lids. However, use of
mason-type jars designed for use in home canning ensures a
safe product and break-free jars during processing.
Other commercial jars with mouths that cannot be
sealed with two piece canning lids are not recommended for
use in canning any foods at home.