Question

Which of the following is the time-temperature combination for HTST pasteurization?

(a) 72°C to 74°C for 15 to 20 seconds

(b) 135°C to 140°C for 2 to 4 seconds

(c) 63°C for 30 minutes

(d) 57°C to 68°C for 15 min

The question was posed to me during an internship interview.

This is a very interesting question from Heat Exchangers in chapter Building Blocks of Dairy Processing of Dairy Engineering

Answer 1

Correct choice is (a) 72°C to 74°C for 15 to 20 seconds

Easiest explanation: High temperature short time (HTST) pasteurization. Heat the milk to between 72°C to 74°C for 15 to 20 seconds. Targets resistant pathogenic bacterial spores (Clostridium botulinum spores).