Question

Given below are two statements:
Statement (I): Boiling of Milk kills the vegetative forms of all organisms including spores
Statement (II): Heat stable enterotoxins of Staphylococcus aureus can not survive under boiling conditions
In light of the above statements, choose the most appropriate answer from the options given below.

• A. Both Statement (I) and Statement (II) are true.
• B. Both Statement (I) and Statement (II) are false.
• C. Statement (I) is true but Statement (II) is incorrect.
• D. Statement (I) is incorrect but Statement (II) is correct.

Hint:

To ensure absolute safety, avoid consuming milk that has been left at room temperature for long periods, as boiling will kill the Staph bacteria but will not destroy their heat-stable enterotoxins.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Standard domestic boiling of milk (\(100^\circ\text{C}\) at atmospheric pressure) pasteurizes the milk by killing standard disease-causing vegetative microorganisms, but it does not sterilize it.

Step 2: Detailed Explanation:
Let us analyze both statements:

• Statement (I): While boiling effectively destroys all vegetative forms of bacteria, yeasts, and molds, it cannot destroy bacterial endospores (such as those of Bacillus and Clostridium species), which require high-pressure sterilization at \(121^\circ\text{C}\). Thus, Statement (I) is False.

• Statement (II): Staphylococcus aureus produces extracellular enterotoxins (such as Enterotoxin A) that are exceptionally heat-stable. These toxins can easily withstand boiling at \(100^\circ\text{C}\) for 30 minutes or more without being inactivated. Thus, even if boiling kills the bacterial cells, the active toxin remains in the milk, causing food poisoning. Thus, Statement (II) is False.

Step 3: Final Answer
Both Statement (I) and Statement (II) are false.