Asked October 18, 2021, 12:35 PM EDT
Marion County Oregon
It is hard to answer your question from just looking at the photo. Questions I have for you. What kind of lid is it? (Brand) How long ago did you can it? Was this taken shortly after canning or after storage? What kind of juice did you can? Did you boil your lids before you put them on and how tight did you screw on the band? Did all the seals do this or just the one with the juice?
From the looks of the photo I would say that it was canned sometime ago. There might have been a reaction with the juice and the seal if it happened to siphon a little during canning. It looks like the rings were put on really tight and if the gasket was heated too much before you put them on.
The spots on the lids is probably a reaction of the juice with the compound. It does happen sometimes, especially with tomato juice and I have also seen it with grape juice. Not harmful.
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