Not sure if this is the right place to ask this or not but maybe the best canners are on here. I've found way on the back of the pantry shelves, about 20 cans of condensed sweetened milk. The expiration date is 2010. Over half of the cans go from slightly bulging to definitely bulging. The other eight cans seem fine. One can was kind of in the middle, had a little give, but almost in discernibly so, so I put that one in the bulge category. The eight that seem OK have no give when I pinch the top and bottom between my fingers and seem fine. If this were any other canned product, say a vegetable or a meat, it probably wouldn't be any good, anyway, and it would be easier to get rid of it. But this is 50% sugar, and probably is in better shape. And if this were something I'd canned myself, I wouldn't question the seals on glass jars if they were tight, even for very old jars, but these steel cans don't behave that way, they go at the seams from what I can tell. Of course, the easy answer, and most likely what I'll end up doing, is tossing everything. But, if these were pressure processed at 15 pounds (those cans that seem OK) for 30 minutes, would they be safe? What if I did the same thing at 75 minutes? Essentially it would be the same as boiling home canned food for ten minutes after opening a jar. If the jars did not pop their seams during this reprocessing, then would it prove they were still OK before the reprocessing? Seems like a compromised can would not be able to take the pressure? Just curious what others think. At the least, I've learned to keep track of the pantry shelves!