Packets of potato chips are usually flushed with which one of the following gases to prevent rancidity?

Potato chip manufacturers flush packaging bags with nitrogen gas to prevent rancidity and oxidation [2]. Rancidity occurs when the fats and oils present in chips react with oxygen in the air, leading to unpleasant smells and tastes [1]. Nitrogen is used because it is a relatively inert gas that effectively displaces oxygen, thereby slowing down the degradation process and extending the product's shelf life [1]. This technique, known as nitrogen flushing or Modified Atmosphere Packaging (MAP), also serves a physical purpose: the gas creates a protective cushion that prevents the brittle chips from being crushed during transportation [3]. While other gases like carbon dioxide can be used in food packaging, nitrogen is the industry standard for snacks due to its non-reactive nature and cost-effectiveness [2]. In contrast, oxygen promotes spoilage, and hydrogen is primarily used for the hydrogenation of fats rather than packaging.

Sources

1. [1] Science , class X (NCERT 2025 ed.) > Chapter 1: Chemical Reactions and Equations > 1.3.2 Rancidity > p. 13
2. [2] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 20: Earths Atmosphere > Nitrogen > p. 272
3. [3] https://www.cfs.gov.hk/english/multimedia/multimedia_pub/multimedia_pub_fsf_177_02.html