Question

What is the reason behind production of large holes in 'Swiss Cheese' ?

• A. The production of large amount of $CO_2$ and $H_2$ by {Trichoderma polysporum}
• B. The production of large amount of $CO_2$ by {Clostridium butylicum}
• C. The production of large amount of $CO_2$ and $H_2$ by lactic acid bacteria called {Lactobacillus}
• D. The production of large amount of $CO_2$ by {Propionibacterium sharmanii}

Hint:

Logic Tip: Link the 'S' and 'P' in the names to remember them! \textbf{S}wiss cheese = \textbf{P}ropionibacterium \textbf{s}harmanii. Roquefort cheese = {Penicillium roqueforti} (fungi).

Answer 1

The Correct Option is D

Concept:
Different varieties of cheese are known by their characteristic texture, flavor, and taste. These specific traits are a direct result of the specific species of microbes (bacteria or fungi) used during the ripening and fermentation processes of cheese production.
Step 1:
Swiss cheese is globally recognized for its distinct appearance, which features large holes (often called "eyes") scattered throughout the cheese block.
Step 2:
During the cheese maturation process, specific bacteria undergo fermentation. The large holes are formed by gas bubbles that become trapped in the solidifying cheese matrix. The specific gas responsible for these large bubbles is a massive amount of Carbon dioxide ($CO_2$).
Step 3:
The specific bacterium utilized in the dairy industry to ripen Swiss cheese and produce this large volume of $CO_2$ is {Propionibacterium sharmanii.
Step 4:

• Trichoderma polysporum (Option 1) is a fungus used to produce the immunosuppressive drug Cyclosporin A, not cheese.
• Clostridium butylicum (Option 2) is a bacterium used to produce butyric acid.
• Lactobacillus (Option 3) is a Lactic Acid Bacterium (LAB) primarily used to convert milk into curd, but it does not produce the massive $CO_2$ bubbles required for Swiss cheese holes.
Step 5:
Therefore, the large holes in Swiss cheese are exclusively due to the $CO_2$ produced by Propionibacterium sharmanii, making Option (4) the correct answer.