Question

The selective criteria for Cheddar cheese cultures are-
A. Rapid acid production
B. Bacteriophage resistance
C. Salt senstivity
D. Ripening activity
Choose the correct answer from the options given below:

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

Hint:

For any cheese culture, think about what it needs to do its job: be a fast worker (rapid acid), be tough (phage resistance), survive the conditions (salt tolerance), and contribute to the final product (ripening). "Salt sensitivity" is the opposite of a desired trait.

Answer 1

The Correct Option is A

Step 1: Concept Overview:
The question focuses on identifying desirable selection criteria for starter cultures used in Cheddar cheese production.
Step 2: Detailed Analysis:
Let's examine each criterion:
A. Rapid acid production: Essential for controlling cheese-making, whey expulsion (syneresis), and achieving the correct texture and pH for cheddaring. A desirable characteristic.
B. Bacteriophage resistance: Crucial. Bacteriophages (phages) can destroy starter cultures, halting acid production and leading to cheese failure. Resistance to phage is vital. A desirable characteristic.
C. Salt senstivity: Undesirable. Cheddar production involves adding 2-3% salt to the curd. The starter culture must be salt-tolerant to function during ripening. Salt sensitivity would disqualify a culture.
D. Ripening activity: Important. Starter bacteria enzymes break down proteins and fats during aging, developing Cheddar's characteristic flavor and texture. A desirable characteristic.
Therefore, key criteria are rapid acid production, bacteriophage resistance, and ripening activity.
Step 3: Conclusion:
The correct selective criteria are A, B, and D.