Why Is There So Much Air In Potato Chip Packets?

Shown below, Illinois Gov Pritzker preparing lunch before inflating his bag of chips with a hand pump.

Why Is There So Much Air In Potato Chip Packets?

Not to sound conspiratorial, but...

By Tom Hale, IfScience

Dec 23, 2024

Popping open a bag of potato chips to find its contents are 90 percent air can be a dispiriting and humbling experience, but there are good reasons why your packets of snacks can sometimes resemble an inflated pillow (or at least that’s what Big Potato wants you to think).

It's commonly said that packets of chips contain a lot of air to help protect them from premature crushing during transit, acting a bit like an airbag. Furthermore, the presence of gas in the bag helps to accommodate for changes in atmospheric pressure, which is important if the food is being transported via plane (or, presumably, space rockets).

The bags are not filled with atmospheric air from the factory, but nitrogen. Left exposed to the open air and oxygen, potato chips can quickly become soft and unappetizing, as you might notice if you leave a packet open overnight.

However, nitrogen helps prevent oxidation of the oils and starches in the chips, helping to keep them fresh and crunchy for longer. This, funnily enough, has been scientifically validated by peer-reviewed studies. Nitrogen is also a good choice because it's non-reactive, odorless, and safe to use in food packaging.

On the other side of the argument, there is some evidence that some potato profiteers may be overfilling their packaging.

Henry Hargreaves, an artist and food photographer, grew increasingly dismayed at the contents of his processed snacks, so carried out a (not-so-scientific) experiment to see whether the airbag-like packaging was actually necessary.

Shock horror: he found that having an abundance of gas in the packet did not help to prevent damage to the contents.

“I assumed the air would stop them breaking, but the reverse happened. The ones with the most air also have the most breakage. I found when I vacuum-sealed them this was the most efficient way to transport and handle them without breaking them,” Hargreaves told BBC Future.

Out of fear of reprisal from Big Potato, we couldn’t possibly speculate on why snack manufacturers haven’t reached the same findings as Hargreaves. However, there is at least one good reason why should reconsider their air-pumping policies.

“For example, 86 out of every 100 trucks carrying Doritos don't need to be on the road. That’s a big carbon footprint,” Hargreaves added.