Question

Which is true about HTST pasteurization?

• A. 63°C for 30 min
• B. 50°C for 10 min
• C. 72°C for 15 sec
• D. 100°C for 5 sec

Hint:

LTLT = old batch; HTST = modern, faster, continuous!

Answer 1

The Correct Option is C

Pasteurization destroys harmful bacteria in milk without altering its taste or nutrition. The two main methods are: LTLT (Low Temperature Long Time) — heating milk at 63°C for 30 minutes in batches; and HTST (High Temperature Short Time) — heating milk at 72°C for 15 seconds using continuous flow systems. HTST is widely used in modern dairy plants because it is faster, energy-efficient, and preserves milk quality.

Answer 2

Recall the Standard Pair: Pasteurization has exactly two named methods, and each has a fixed time-temperature combination — memorize both as a pair.

LTLT = 63°C for 30 minutes (batch method). HTST = 72°C for 15 seconds (continuous-flow method) — this is what the question asks for.

50°C/10 min is too mild to be a real pasteurization standard, and 100°C/5 sec would scorch the milk, so both are eliminated on physical grounds alone.