Use fruit fresh. It is in the canning section along with the jars and etc.That plum jelly looks good!
I was looking at plums in the store yesterday - I need to make another batch of Plum Sauce.
Question - The last batch of Plum sauce I made turned brown - the first 2 batches stayed a nice cheery red color, but the brown is a little off-putting for DH. I used black plums from the grocery store. Should I buy red plums instead? They are harder to find for some reason.
Now that I have a steam canner, it is so much more convenient to can stuff than the whole boiling water bath process.