Question

UV radiation are excellent for food processing except for the fact that ________. 
 

• A. They have poor penetration power
• B. They are not safe
• C. They may induce radioactivity
• D. They generate a lot of heat

Hint:

UV-C light is an effective non-thermal surface sanitizer, but it cannot penetrate turbid liquids or solid food interiors. This poor penetration limits its use to surface and air disinfection.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Ultraviolet (UV) radiation (specifically UV-C light in the range of $200\text{ to }280\text{ nm}$) is used as a non-thermal decontamination method in the food industry to sanitize surfaces, air, and clear liquids.
Detailed Explanation:
The primary limitation of UV radiation in food processing is its poor penetration power (A).
- UV light is electromagnetic radiation with a short wavelength, meaning it is easily absorbed, reflected, or scattered by solids, suspended particles, and turbid liquids.
- As a result, its germicidal effect is limited strictly to the surface of solid foods or the thin outer layer of flowing liquids.
- It cannot penetrate food packaging materials, opaque liquids (like milk), or solid food interiors.
Evaluating the other options:
- UV-C is safe when operated within enclosed processing equipment (B).
- It does not contain enough energy to induce radioactivity in food (C).
- It is a non-thermal process that does not generate significant heat (D).

Step 2: Final Answer:
The main disadvantage of UV radiation in food processing is its poor penetration power.