Question

According to FSSAI standards continuous flow process must be applied for

• A. Pasteurised milk
• B. Sterilised milk
• C. UHT treated milk
• D. Boiled milk

Hint:

UHT treatment is fundamentally defined as a continuous-flow thermal process followed immediately by aseptic packaging to achieve commercial sterility.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Ultra High Temperature (UHT) processing is a thermal preservation method designed to render milk commercially sterile.
Due to the extreme temperatures required, this process must be conducted in a continuous, closed system to prevent boiling and avoid severe chemical degradation of the milk.

Step 2: Detailed Explanation:
FSSAI regulations define UHT treatment as heating milk to a temperature of 135$^\circ$C to 150$^\circ$C for a short holding time (typically 2 to 6 seconds).
This rapid heating and subsequent rapid cooling must be executed in a continuous-flow heat exchanger (either direct steam injection/infusion or indirect plate/tubular systems).
A batch system cannot achieve these high temperatures rapidly enough without causing severe caramelization, protein coagulation, and nutrient loss.
Following the continuous flow heating and cooling steps, the milk is packaged aseptically into sterile containers.
While pasteurized milk can be processed via continuous-flow (HTST) pasteurization, FSSAI also permits batch (LTLT) pasteurization.
Sterilized milk is traditionally sterilized inside its final container (in-bottle sterilization) using batch or continuous hydrostatic retorts, rather than requiring a continuous flow process before packaging.
Therefore, a continuous flow process is a mandatory requirement specifically for UHT treated milk.

Step 3: Final Answer
The correct option is (C).