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 canning process heats the food to a safe temperature while also creating a vacuum and sealing out pathogens that could potentially get into the food. This creates an environment in which it is highly unlikely for harmful bacteria to grow, resulting in a more shelf stable food. Fresh meats are exposed to oxygen, which most harmful food-borne bacteria need in order to reproduce.