Cheese is spoiled milk -- and this is truer if the cheese is actual cheese rather than "cheese food" of "processed cheese".

There is a nice discussion of this in "On Food and Cooking" by Harold McGee (second edition). In the first edition, he gives an overview of the role of cheese in history as it is one of the ways that the warmer European countries could preserve milk - since they had no refrigeration facilities. The Northern Barbarians could drink more of their milk because of the cooler temperatures and were called the "milk eating barbarians". To differentiate thm from the civilized southern people who ate cheese.

There are several real cheeses which you can buy which are wrapped in wax.

I mailed my food supplies to different post offices in June, and opened the last of them just a week ago. The cheese was perfect after setting uncut in the wax coating with NO REFRIGERATION.

In some of the little country stores, they were selling cheese in little plastic wrappers. I asked them how long it would keep and they said "if it develops green mold, just cut it off and continue eating". I believe that McGee says something similar.

I suspect that jelly is generally, but not always, marked "refrigerate after opening" (RAO). I had bought some of the brand that did not have the RAO on it and it was fine repackaged and taken on hiking trips.

Some "RAO" is put on packages to "CYA" or "cover your arse" by the food manufacturers, and their lawyers.

I routinely take summer sausage on bike and backpacking trips and eat each sausage in two days or less, storing it in a plastic baggie.

There are Italian Sausages and Hard Salami products you can buy unrefrigerated in the stores that have listed shelf lives of as long as a year or more after purchase. Bridgeford is the brand name I encounter. It is no trick to eat a 12 oz sausage product in two days. If you look at the ingredients list, you will find LOTS OF PRESERVATIVES. It won't spoil 30 minutes after opening if it had a shelf life of over a year when you bought it.

It helps if you try to think through how long mankind has lived without refrigeration and what that has meant for classic foods like eggs, jelly, meats with ancient preservative techniques ....... and more. Jelly is after all a preservation method for fruits, much as is drying.