Question

High temperature short time (HTST) pasteurization of milk is done at

• A. 72°C for 15 seconds
• B. 80 °C for 10 seconds
• C. 95 °C for 5 seconds
• D. 100 °C for 3 seconds

Hint:

HTST pasteurization: $72^\circ\text{C}$ for $15\,\text{seconds}$; LTLT (Vat): $63^\circ\text{C}$ for $30\,\text{minutes}$; UHT: $135\text{--}150^\circ\text{C}$ for $1\text{--}2\,\text{seconds}$.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Commercial thermal pasteurization regimes are standardized to eliminate index pathogenic vegetative bacteria (Coxiella burnetii and Mycobacterium tuberculosis).

Step 2: Detailed Explanation:
High Temperature Short Time (HTST) continuous flow pasteurization applies thermal treatment at $71.7^\circ\text{C}$ to $72^\circ\text{C}$ ($161^\circ\text{F}$) for a holding time of 15 seconds in plate heat exchangers, followed by rapid chilling to $< 4^\circ\text{C}$.
Low Temperature Long Time (LTLT) vat pasteurization operates at $63^\circ\text{C}$ for 30 minutes.

Step 3: Final Answer:
Hence, HTST pasteurization is performed at 72°C for 15 seconds.