Wait - perhaps that was silly to say. Does jam need to be canned in order to .... jell or whatever it is?
>>>Wait - perhaps that was silly to say. Does jam need to be canned in order to .... jell or whatever it is?<<<
Nope...
I am sure you are too young to remember, but others on here will tell you that they have eaten many many a jar of jam or jelly that was poured hot into a jar and then melted paraffin was poured on about a half inch thick to form a seal.
If you didn’t put a cover on it, the mice would eat through it and sometimes you needed to scrape the mold off with the paraffin - and sometimes you got little flakes of wax in the jam - all things that people today would frown on...
Ever notice they put pound boxes of paraffin wax in the canning sections of stores.... Well, that was what it was for.