I was just watching this program on the food network here and they were talking about the Spanish fermented pork sausages. It made me think of sausages that are hung to dry and even though its raw meat (which would go bad very very quickly if not refrigerated properly), it doesn't go bad. Why is that? Is it because no air touches the meat inside the casings?
It is due to a combination of several factor, depending on how the particular sausage was made: