Which type of radiation is NOT used for food preservation?

Alpha radiation is not used for food preservation due to its limited penetration ability. Alpha particles, consisting of two protons and two neutrons, are relatively large and have a low penetration power; they can be stopped by just a sheet of paper or the outer layer of human skin. This makes them ineffective for sterilizing food products or killing bacteria, viruses, and parasites that may be present in food items.

In contrast, gamma radiation, X-rays, and electron beams all have higher penetration capabilities, allowing them to effectively reach and treat food products to extend shelf life and improve safety. Gamma radiation, in particular, is commonly used in food preservation as it effectively destroys harmful microorganisms. X-ray and electron beam technologies are also utilized in various food processing applications for similar reasons. The ability to penetrate deeply into the food and eliminate pathogens without significantly altering the food's chemical properties is essential for effective food preservation methods.