Question

Which of the following statements are correct?
A. Mishti doi is popular in the eastern part of India
B. Yakult contains Lactococcus casei
C. Bacteriocin can be used as a food preservative
D. The creatinine test is conducted to evaluate the ability to produce acidity by lactic acid bacteria
Choose the correct answer from the options given below:

• A. A and B only
• B. A, B and C only
• C. A and C only
• D. A, B, C and D

Hint:

Dairy Facts:
Mishti Doi $\rightarrow$ Eastern India (Bengal/Odisha).
Yakult $\rightarrow \textit{Lactobacillus casei Shirota}$ (NOT Lactococcus).
Bacteriocins (Nisin) $\rightarrow$ Natural food biopreservatives.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Indigenous dairy products, commercial probiotic microbiology, and natural biopreservatives in dairy technology.

Step 2: Detailed Explanation:
Evaluating the individual dairy science statements:
1. A. True: Mishti Doi (sweetened caramelized fermented curd) is a famous, culturally historic traditional indigenous fermented dairy product extremely popular in the eastern part of India (West Bengal, Odisha, Assam).
2. B. False: The world-famous probiotic fermented drink Yakult contains Lactobacillus casei strain Shirota (Lacticaseibacillus paracasei), NOT Lactococcus casei.
3. C. True: Naturally synthesized antimicrobial peptide Bacteriocins (e.g., Nisin A from Lactococcus lactis, Pediocin) are approved and widely used as safe bio-preservatives in cheese, canned foods, and dairy desserts to inhibit sporeformers and Listeria.
4. D. False: The creatinine test evaluates urea/creatinine adulteration, not bacterial acid production.
Thus, statements A and C only are correct.

Step 3: Final Answer:
Hence, statements A and C only are correct, corresponding to option (C).