Question

Which of the following processes that are used in the production of safe and commercially sterile milk and milk products?
(A). Pasteurization,
(B). UHT sterilization
(C). Aseptic processing
(D). Thermization
Choose the correct answer from the options given below:

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

Hint:

Thermization is merely a temporary pre-treatment used to extend raw milk storage time and does not replace pasteurization or sterilization as a safety step.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Thermal treatments in the dairy industry are classified by their processing temperatures and objectives, ranging from mild sanitization to complete commercial sterilization.

Step 2: Detailed Explanation:
Let us evaluate each thermal process:

• (A) Pasteurization: A heat treatment designed to eliminate all vegetative pathogens, making the milk biologically safe for consumption. (Correct)

• (B) UHT sterilization: Ultra-High-Temperature heating (typically \(135\text{--}140^\circ\text{C}\) for 2–4 seconds) designed to destroy all viable microorganisms and their highly resistant spores. (Correct)

• (C) Aseptic processing: Packaging sterilized milk in pre-sterilized containers under sterile conditions, ensuring the product remains commercially sterile at room temperature. (Correct)

• (D) Thermization: A mild sub-pasteurization heat treatment (typically \(63\text{--}65^\circ\text{C}\) for 15 seconds) used only to temporarily suppress psychrotropic bacteria before processing, and does not yield a safe or sterile finished product on its own. (Incorrect)
Thus, processes (A), (B), and (C) are used to produce safe and commercially sterile milk, while (D) is excluded.

Step 3: Final Answer
The correct combination is (A), (B) and (C) only.