Leaving rings on, promotes rust in a damp atmosphere. If you've been leaving them on and no problems, don't worry about it. Some people also feel leaving bands on protects the jars from breakage / chips. OTOH, rings can be expensive, I priced WIDE MOUTH box of 12 bands and flats yesterday at $5.69 I think.
Take them off. for one it's better to have a jar that is not properly sealed -open up and you can be aware of it. 2- from the processing there could be moisture,food ect, under the ring-do you really want that molding and messing with the rubber seal. 3- use the rings on other canning projects.
The slightest bit of dampness will rust them. If bad enough, they almost fuse themselves to the glass and I'd worry about breaking the jar while using a lid wrench to open one like that. At same time, I have bought cases of old jars which had rings on to prevent chipping. If they were stored in a damp area, same thing applies. In both cases, best to destroy the ring by removing it with a pliers.
I used to leave them on but then had all kinds of failed seals months later and discovered the hard way what was causing them. It was the molds, grease, and food particles trapped under the rings. Plus the rust issues as others have mentioned. Now I find it is much better to remove them as recommended by the guidelines.
Thanks y'all. I am trying to organize my new food storage room and it got me wondering about all those rings. I went ahead and took them off the jars I have left in the cabinets. That created another problem - what to do with them. I finally found a couple of plastic storage boxes that they would all fit in. Will they be okay in those?
You can make a huge round safety pin thing from a coat hanger and hang them up on that. I simply toss my regulars into a plastic waste basket type container that just nicely fits on the bottom shelf in the pantry. Widemouths and #63s just have their separate cardboard boxes.
If you are planning on entering them in any fairs remove them, it could be the most beautiful canning job ever done, and you will lose for the rust. Plus I always feel uncomfortable using anything with rust. They may be cheap, but i know on my shoestring budget, even canning lids can be to much.
I learned the hard way. Left mine on the first time I canned and you would not believe the trouble we had getting them off. No actual evidence of rust underneath, but they were, as a previous poster said, basically fused to the glass and yes, we did break some jars getting them off before I mentioned it to my MIL and she told us the secret: if your rings get stuck submerge them in warm water. Within a couple of minutes they free right up and you can twist them off as usual. I take them all off as soon as the jars have cooled now though. Much easier that way.
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