Which of the following processes is used in food preservation in an industry?

Analyze the question: It asks which process is used to preserve food in industry. Option B ("Ieeadiation of gamma rays") is a typo for irradiation of gamma rays.

Explain the concept: Food irradiation exposes food to controlled doses of gamma rays, usually from the radioisotope Cobalt-60 (or Caesium-137). The radiation:

• Kills bacteria, moulds and other microorganisms that cause spoilage
• Destroys insects and parasites
• Delays ripening and sprouting (for example in yams and potatoes)
• Does not make the food radioactive, and it leaves the food nearly unchanged in temperature, so it is often called "cold sterilisation"

Check each option:

• A. Carbon dating: This uses the decay of Carbon-14 to find the age of fossils, wood and archaeological objects. It has nothing to do with food preservation.
• B. Irradiation of gamma rays: This is a true industrial preservation method, as explained above.
• C. Nuclear fission: This splits heavy nuclei such as Uranium-235. It is used in nuclear reactors and atomic bombs to produce energy.
• D. Nuclear fusion: This joins light nuclei such as hydrogen to form helium. It is the energy source of the sun and hydrogen bombs.

Tip: Link each radioactivity use to its field:

• Carbon-14 → dating
• Cobalt-60 gamma rays → food preservation and cancer treatment (radiotherapy)
• Iodine-131 → thyroid treatment
• Fission/fusion → energy

Remember "Gamma = Guards food from germs."