Which organism is specifically destroyed in pasteurization?

Question

Question

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KGMU Nursing Officer 2023 Memory-Based Previous Year Paper

Answer 1

Correct Answer: Mycobacterium tuberculosis

Rationale:

Pasteurization is a process of heat treatment used to kill or inactivate harmful microorganisms in food and beverages, particularly milk, without compromising their nutritional quality or flavor.
The primary goal of pasteurization is to destroy pathogenic microorganisms that can cause diseases. Mycobacterium tuberculosis is a significant pathogen specifically targeted by pasteurization, as it can be transmitted through contaminated milk and cause tuberculosis in humans.
The standard pasteurization method, such as high-temperature short-time (HTST) pasteurization (heating milk to 72°C for 15 seconds), is effective in killing Mycobacterium tuberculosis along with other pathogens like Brucella and Salmonella.
The destruction of Mycobacterium tuberculosis during pasteurization is critical for public health, especially in regions where bovine tuberculosis is prevalent.

Explanation of Other Options:

Clostridium botulinum

Rationale: Clostridium botulinum is a bacterium that produces botulinum toxin, which causes botulism. It forms heat-resistant spores that are not effectively destroyed by standard pasteurization methods. High-temperature sterilization (above 121°C) is required to inactivate these spores.

Bacillus cereus

Rationale: Bacillus cereus is a bacterium that can cause foodborne illness. Its spores are also heat-resistant and can survive pasteurization. While pasteurization may reduce the number of vegetative cells, it does not entirely eliminate Bacillus cereus spores.

Lactic acid bacteria

Rationale: Lactic acid bacteria are generally non-pathogenic and are often beneficial in food production, such as in the fermentation of yogurt and cheese. Pasteurization may reduce their numbers, but they are not the primary target of this process.

Conclusion:

Pasteurization is specifically designed to destroy pathogenic microorganisms like Mycobacterium tuberculosis, which pose significant health risks when consumed via raw milk or other unpasteurized products. While the process may have some impact on other microorganisms, it is not effective against heat-resistant spores like those of Clostridium botulinum or Bacillus cereus. Lactic acid bacteria are not targeted as they are generally harmless or beneficial.