There’s a distinct chance we’ve been canning all wrong. Or, at the very least, storing our canned jars in the wrong ways.
According to The Kitchn, leaving the rings on canning jars during storage may encourage the growth of mold, rust, and even vermin. These certainly don’t go well with fresh batches of tomato jam. Read about proper storing etiquette - and how to keep your precious jams, jellies, and pickles safer - in their detailed how-to. Then go unscrew all of the rings on your jars; you’ll be glad you did.
Tip: Store Canned Jars Without Rings from The Kitchn