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- Why are my canning lids popped out? 1 answer
I canned a bushel of pickles 2 weeks ago. When I finished up that morning, all the jars were sealed. This morning I noticed that about a dozen jars were not sealed. Just the opposite. The lids were puckering out to the point of bulging the lids out. I have been canning for more than ten years and I have never seen this before. What would cause this and are they safe?