Science question, what's growing in these cans?

If one of these cans got a small hole in it, I would not have been surprised to find it all puffed out in my cupboard. But this happened to two cans at the same time, neither of which is leaking. (The pink on the bottom of the one in the third image is my tee shirt reflection.) The expiration date was 2009. They've been fine in the cupboard until recently. I ate the fruit from other cans from the batch, never got sick, nothing was wrong with them.

I've never seen anything like this before. Can goods would have been sterile inside.

Surely it's not like the idiot Chuck Missler's evolution in a sealed peanut butter jar. Maybe I should send one to him and suggest it is evidence of abiogenesis? :p

Kidding aside, what happened here? What would cause bacteria to grow in sterile can contents years after they sat on a shelf? Or is this some form of aseptic breakdown? That makes no sense to me without bacteria or fungus action.

via International Skeptics Forum http://ift.tt/2wzv0N5