Question

Which microorganism is used in yoghurt production?

• A. \textit{Streptococcus thermophilus}.
• B. \textit{Streptococcus penicillium}.
• C. \textit{Penicillium roqueforti}.
• D. \textit{Aspergillus niger}.

Hint:

The combination of \textit{Streptococcus thermophilus} and \textit{Lactobacillus delbrueckii} is essential for the production of yoghurt, ensuring its texture and flavor.

Answer 1

The Correct Option is A

Step 1: Role of microorganisms in yoghurt production.
Yoghurt is produced through the fermentation of milk using specific bacteria. \textit{Streptococcus thermophilus} and \textit{Lactobacillus delbrueckii subsp. bulgaricus} are commonly used starter cultures. Step 2: Explanation of other microorganisms.
\textit{Streptococcus penicillium (Option B):} Incorrect. This is not a known species used in yoghurt production. \textit{Penicillium roqueforti (Option C):} Incorrect. This fungus is used in the production of blue cheese, not yoghurt. \textit{Aspergillus niger (Option D):} Incorrect. This fungus is used for industrial production of citric acid, not yoghurt. \[ \therefore \text{The correct answer is: \textit{Streptococcus thermophilus}.} \]