Question

Given below are two statements:
Statement (I) : Traditional acidophilus milk is prepared by inoculating Lactobacillus acidophilus culture at the rate of 2–5% in autoclaved or severely boiled milk.
Statement (II) : Traditional acidophilus milk has tartness and a strong cooked flavour.
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 false.
• D. Statement (I) is false but Statement (II) is true.

Hint:

Severe heat treatment of milk is a absolute requirement for traditional acidophilus milk.
This ensures no competitor bacteria survive and generates the characteristic cooked flavor and high tartness.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Acidophilus milk is a traditional therapeutic fermented milk product prepared using a pure culture of Lactobacillus acidophilus, which is a slow-growing, highly beneficial intestinal probiotic bacterium.

Step 2: Detailed Explanation:
Let us analyze the manufacturing parameters of traditional acidophilus milk:
- Statement (I) describes the inoculation and heat treatment steps.
Because Lactobacillus acidophilus is a slow-growing organism that is easily outcompeted by other bacteria, the milk must be subjected to intense heat treatment (severe boiling or autoclaving at $121^\circ\text{C}$ for 15 minutes) before inoculation.
This treatment ensures complete sterility and releases essential growth-promoting peptides.
The sterile milk is then cooled to $37^\circ\text{C}$ to $40^\circ\text{C}$ and inoculated with an active culture of L. acidophilus at a high rate of \( 2\% \) to \( 5\% \).
Thus, Statement (I) is true.
- Statement (II) describes the sensory attributes of the finished product.
Because of the long fermentation time required for L. acidophilus to reach a high acidity of around \( 0.85\% \) to \( 1.0\% \) lactic acid, the product possesses a distinct tartness.
Additionally, the severe heat treatment (autoclaving/boiling) used to sterilize the milk prior to fermentation causes Maillard browning and whey protein denaturation, imparting a strong, distinct cooked flavor to the finished product.
Thus, Statement (II) is true.
Therefore, both Statement (I) and Statement (II) are true.

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