The safe internal temperature for pork is 145°F, but for ribs to be “fall-off-the-bone” or “melt-in-your-mouth” tender, they need to cook slow and low for a long time to gradually reach an internal temperature of around 185/190°F. (Collagen is what makes meat tough, and the collagen in the ribs will begin breaking down at around 160°F but needs to get to around 185/190°F to really tenderize.)