Question

Match the enzymes in milk from List-I with their association in List-II and select correct series from the options.
\begin{tabular{ll} List-I (Enzyme) & List-II (Association)
A. Lipoprotein lipase & 1. Mastitis indicator
B. Lactoperoxidase & 2. Age gelation in UHT milk
C. Catalase & 3. Homologous with alpha lactalbumin
D. Plasmin & 4. Indicator of HTST pasteurisation
E. Lysozyme & 5. Rancid flavour
F. Alkaline phosphatase & 6. Bactericidal activity

Choose the correct answer from the options given below:

• A. A-5; B-6; C-1; D-4; E-2; F-3
• B. A-5; B-6; C-1; D-2; E-3; F-4
• C. A-1; B-6; C-5; D-2; E-3; F-4
• D. A-6; B-3; C-1; D-2; E-5; F-4

Hint:

Alkaline phosphatase is the classic indicator of pasteurization (F - 4).
Lipoprotein lipase causes rancid off-flavors in milk fat (A - 5).
Matching these two instantly identifies the correct option.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Milk contains various indigenous enzymes synthesized by the mammary gland or derived from blood plasma and somatic cells.
These enzymes serve as key indicators of milk quality, processing efficiency, and disease states.

Step 2: Detailed Explanation:
Let us correlate each enzyme in List-I with its correct association in List-II:
- A. Lipoprotein lipase: This enzyme hydrolyzes milk fat triglycerides into free fatty acids, leading to hydrolytic rancidity and a highly objectionable Rancid flavour (5).
- B. Lactoperoxidase: This heat-resistant enzyme is part of the lactoperoxidase system (LP-system), which exhibits potent natural Bactericidal activity (6) against pathogens.
- C. Catalase: Catalase is present in high concentrations in somatic cells (white blood cells).
Its concentration rises dramatically in mastitic milk, making it a valuable Mastitis indicator (1).
- D. Plasmin: This is an indigenous protease in milk.
It is highly heat-stable and can survive UHT processing, slowly degrading caseins during storage, which causes Age gelation in UHT milk (2).
- E. Lysozyme: This antimicrobial enzyme is structurally and evolutionarily Homologous with alpha lactalbumin (3).
- F. Alkaline phosphatase: This enzyme is inactivated at temperatures slightly higher than those required to kill vegetative pathogens.
Testing for its inactivation serves as the official Indicator of HTST pasteurisation (4).
This gives the match: A-5, B-6, C-1, D-2, E-3, F-4.

Step 3: Final Answer:
The correct matching sequence corresponds to option 2.