When you buy a bag of chips or whatever it will stay fresh for a long time but once you open the bag it will only last for a few days. How is this possible?

Question

Like there is air in the bag as well so how come it can last for longer period of time when sealed?

In: Earth Science

Answer 1

Humidity is controlled in the bag, the inside of the bags are sterile, so there is no bacteria inside. The air they are filled with isn’t standard “room air” but nitrogen, which is inert.