How does a sealed container preserve food safely at room temperature for months/years, but a sealed contained of leftovers in the fridge spoils in less than a week?

Question

For dinner today, I had a liquid precooked curry mix (sauce, cooked veggies etc..) that comes in a little foil pouch and doesn’t have to be refrigerated- just heat the pouch in hot water for 5 minutes and pour over cooked rice. All the food is precooked, just chilling at room temperature in that pouch for months, but perfectly safe to eat.

How can it be so safe and not-spoiled like that, when the same ingredients sitting in a Tupperware in the fridge will go bad in just a few days?

In: Chemistry

Answer 1

The food is sealed and then cooked so it kills off any pathogens and sterilizes the food. It’s sealed off from any elements getting inside there after that so it stays good. Refrigeration slows down the process of food spoiling, usually just gives you enough time to eat your leftovers, but since they are exposed to the air for some time, they are inoculated with bacterial and it starts to grow. If you can keep every cell of bacteria and mold out of things they will stay good for quite some time.