Don't you hate when you pull open a fresh bag of chips and you find SO much empty space? Who are potato chip companies trying to fool?
It may look like they are filled with air. But, the bag is actually packed with Nitrogen gas. Nitrogen gas doesn't react with other molecules around it. Nitrogen is found as a diatomic molecule (N2) in nature. There is a triple bond between the two nitrogen atoms.The triple bond is pretty strong. Therefore, it needs a lot of energy to break those bonds and participate in a reaction. So nitrogen is commonly referred to as and used as an inert gas (high abundance & low cost.)
This makes Nitrogen an excellent preserver. It keeps the chips crispy. It also extends their shelf life. Plus, nitrogen is odourless and tasteless. So, the chips taste just as if they were just made. While our atmosphere is 78 percent Nitrogen, you don't want regular air in your potato chip bag. This is because, oxygen in the air reacts with the compounds in the chips and makes them go stale. This is why chips start to get stale after opening the bag. While, you probably shouldn't eat an entire bag after opening, it is the best way to get the most flavour for your bite.