Because the gas in the potato chip bag is not air, but nitrogen. Potato chips are fried foods that contain a lot of fat and protein. As a result, many potato chip manufacturers are paying close attention to preventing crispy chips. If potato chips are exposed to oxygen for a long time, a large amount of the fatty acids in them will be oxidized, giving off a foul odor often called "saliva smell." Additionally, the moisture in the air not only makes the chips soggy, but is also very conducive to the growth of bacteria. Therefore, potato chips must go through a nitrogen flushing process during the packaging process, and a 1994 study also proved that this method can maintain crispness and fresh taste.

This does provide cushioning and helps the chips adapt to changes in air pressure. In order to avoid consumer misunderstandings, the quality supervision department requires that the net content of all foods in inflatable packaging must be stated. Unfortunately, humans are born without an intuitive concept of mass or volume. So, no matter how obvious the number is, the vast majority of people open too few packages.

Currently, potato chips are packaged in bags and barrels. Bagged potato chips are mainly made of aluminum-plastic composite film or aluminum-plastic composite film. Canned potato chips are basically made from paper-aluminum composite barrels. The above packaging forms can meet the requirements of high barrier properties and good sealing properties.

To ensure that potato chips are not easily oxidized or crushed, potato chip manufacturers fill the inside of the packaging with nitrogen, that is, nitrogen-filled packaging, and rely on inert gases such as nitrogen to prevent the presence of oxygen in the packaging. If the packaging material used for potato chips has poor nitrogen barrier properties, or the packaging of potato chips is not tightly sealed, the nitrogen or oxygen content in the packaging will easily change, making the nitrogen-filled packaging unable to protect the potato chips.