Question

Potato chips manufacturers fill the packet of chips with nitrogen gas. Why?

Answer 1

The major factor for long-term preservation of potato chips is removing oxygen from the containers because the presence of oxygen causes the food to deteriorate. Thus, if the food is packed with nitrogen, it ensures an oxygen free environment which in turn allows the food materials to be stored longer.

Complete step by step answer:
- Nitrogen has a very long history in food manufacturing and packaging processes. It slows down the food deterioration and improves longevity.
- As we know, the gaseous nitrogen has unique physical and chemical properties that make it suitable for use in food packaging. Nitrogen being inert, will not react with prepared food materials, which can alter their flavors or aromas.
- In the process of packaging food with nitrogen, the first step involves the removal of oxygen from the food package. This is because, if food materials such as potato chips which contain fat and oil come in contact with the surrounding oxygen it leads to auto-oxidation and this will lead to change in taste and bad smell and the whole process is known as rancidity.

- Rancidification is the process of decomposition of oils, fats and other lipids by oxidation or hydrolysis or both. Oxidation of fats is mainly caused by a biochemical reaction between oxygen and fats and in this process the long-chain fatty acids are decomposed and short-chain compounds are produced.
-So, we must avoid the presence of oxygen in order to stop the fats going rancid, discoloration of the food and thus to prevent the spoiling of food products. Therefore, if we use gaseous nitrogen it will effectively displace oxygen and thus will minimize oxidation and the growth of microorganisms that cause foods to deteriorate faster and lose their freshness.
- Another reason food manufacturers use nitrogen gas for food packaging is to provide a pressurized atmosphere which prevents package collapse. It helps to ensure that more delicate foods, such as crackers and potato chips, won’t get crushed in the bags where they are stored.

Note: Another important method used in the food industry to avoid the food deterioration is vacuum packaging in which the oxygen or air is entirely removed. This process can be used for sturdy foods like fresh meat and beef jerky, but cannot be used for delicate foods like potato chips and crackers since they also need protection during transportation so that they wouldn’t get crushed or broken down.