University of California, Davis, has this to say on the preservation of melons, cantaloupes, specifically:
METHODS FOR PRESERVING CANTALOUPE
Prepare melons by washing and cutting as described above.
Freezing Cantaloupe
Select fully ripe but firm cantaloupe. Cut the melon into slices, balls, or cubes. After
freezing, melons are best used while still frosty.
Unsweetened Melon
Freeze layers of melon between wax paper. Package in plastic bags or containers once
frozen. Melon should be used within 1 month. These are best if served slightly frozen.
Drying Cantaloupe—Not Recommended
Cantaloupe and other melons are not well suited for drying or for making into fruit
leather. This method of preservation is not recommended.
Canning Cantaloupe—Not Recommended
Cantaloupe and other melons should not be canned. Cantaloupe and other melons
are nonacidic (have a high pH), with pH values ranging from 6.1 to 6.6. Nonacidic
canned fruits support the growth of the bacterium that causes botulism when given
the right conditions, which include moisture, room temperatures, lack of oxygen, and
low-acid conditions. The high pH means that the product would need to be canned
using a pressure canner rather than a water bath canner to ensure product safety. Safe
processing times have not been determined because the high temperatures that would
be needed leave the melon mushy and inedible.
Cantaloupe preserves or pickle recipes from reliable sources can be safely
processed using a water bath canner because the addition of acids or acidic ingredients
safely lowers the pH.With a desire to can cantaloupes, the problem is apparent after this warning. The risks with the growth of bacterium that causes botulism are too high. The second thing is:
The high pH means that the product would need to be canned
using a pressure canner rather than a water bath canner to ensure product safety. Safe
processing times have not been determined because the high temperatures that would
be needed leave the melon mushy and inedible.
For the time being, cantaloupe and other watery melons will have to be enjoyed "in season" rather than in a glass jar stored in our cool cellars. I was sure a way to preserve them (other than freezing) could be found. Is this answer the last word on canning cantaloupes? IOW, I am open to suggestions because my desire to preserve without freezing is very strong. Anyone with experience or suggestions?