Liquid Nitrogen

• Context (TH): FSSAI instructed Food Safety Officers to take enforcement action against any Food Business Operator who is using liquid nitrogen for direct consumption along with food items.
• Liquid nitrogen is inert, colorless, odorless, noncorrosive, nonflammable, and extremely cold.
• Industrial production of pure liquid nitrogen is achieved by distilling it from liquid air. To get the air to a liquid state, it undergoes a liquefaction process by means of strong compression by pistons, and then it is cooled to very low temperatures.
• Liquid nitrogen is formed when nitrogen is cooled to temperatures far below zero (below -195.8°C).

Applications of Liquid Nitrogen

1. It is used in cryotherapy to remove skin abnormalities and serves as a source of dry gas.
2. Freezing and transporting of food products.
3. Cooling of superconductors like vacuum pumps, and other equipments.
4. Cryopreservation of blood, biological samples like eggs, sperm, and animal genetic samples.
5. Cryosurgery (removing dead cells from the brain).
6. Creating Nitrogen fog, making ice cream, flash-freezing.

Hazards

• It has a large expansion ratio on evaporation. Even a small volume of liquid nitrogen can cause oxygen deficiency in the body.
• Liquid nitrogen can scorch the organ or part of the body it contacts, making it appear like frostbite.
• It can damage the lips, tongue, throat, lungs, and stomach and may cause lesions or burn tissues.
• If it reaches the stomach, the organ could get perforated.
• In the lungs, it could produce CO₂ and the person could become unconscious.