Eli5 How can canned meats like fish and chicken last years at room temperature when regularly packaged meats only last a few weeks refrigerated unless frozen?

Question

Eli5 How can canned meats like fish and chicken last years at room temperature when regularly packaged meats only last a few weeks refrigerated unless frozen?

In: Chemistry

Answer 1

The process of canning includes a step after the vessel containing the food is sealed where the contents are heated above a temperature where bacteria can survive thus killing all the bacteria. Since it is sealed no new bacteria can get and cause the meat to spoil.

In contrast, refrigeration does not kill off all the bacteria. It merely slows their multiplication significantly so it takes a lot longer to go bad than at room temperature but it is in fact slowly becoming more infested with bacteria every second. It’s just kept below a level where it will hurt us for as long as possible.