Michigan State University Extension
Preserving Food Safely - 01600542
Jelly glasses or canning jars may be used as containers for jellied fruit products. Be sure all jars and closures are perfect. Discard any with cracks or chips; defects prevent airtight seals.
Get glasses or jars ready before making the jellied product. Wash containers in warm, soapy water and rinse with hot water. Sterilize jelly containers in boiling water for 10 minutes. Keep the containers in the hot water until they are used. This will prevent containers from breaking when filled with hot jelly or jam.
Wash and rinse all lids and bands. Metal lids with sealing compound may need boiling or holding in boiling water for a few minutes -- follow the manufacturer's directions. Use new lids; bands and jars may be reused.