Question

Maximum heat induced changes can be observed in:

• A. Channa
• B. Milk powder
• C. Condensed milk
• D. Khoa

Hint:

Open-pan concentration (Khoa) is the most intense heat treatment among indigenous dairy products, which gives Khoa its characteristic cooked/caramelized flavor and dark hue.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
Heat treatment of milk leads to various physicochemical alterations, including whey protein denaturation, lactose-protein interactions (Maillard browning), and caramelization. The severity of these changes depends on temperature and heating duration.

Step 3: Detailed Explanation:
Let us compare the manufacturing processes of the options:
1. Channa: Prepared by coagulating hot milk with an organic acid. The heat exposure is brief.
2. Milk powder: Spray drying involves extremely rapid moisture evaporation where droplets are exposed to heat for only a few seconds, minimizing heat damage.
3. Condensed milk: Evaporated under a vacuum at relatively low temperatures to minimize heat damage.
4. Khoa: Prepared by continuous boiling and desiccation of milk in an open pan with constant stirring. This prolonged, direct high-temperature exposure leads to maximum protein denaturation, severe Maillard browning, and caramelization of lactose.
Thus, Khoa exhibits the maximum heat-induced changes.

Step 4: Final Answer
The correct option is (D).