The other day I took out a cubed pineapple from the fridge, and when I tasted it it tasted like it started to go "bad." But it actually tasted pretty good and I figured that kimchi and other foods are fermented and they are considered edible and healthy even. So that got me thinking, how can you tell if something gone past their date is fermented in a good way, or in a bad way (gone rancid)? Even meats are "aged" which means they start to decompose.. but that's considered a delicacy.

So how can you tell if it's good or not? Or only the process in which you used can somehow tell if the end product is safe to eat?