Question

Given below are two statements, one is labelled as Assertion (A) and other one labelled as Reason (R).
Assertion (A): Single stage homogenization increases viscosity considerably.
Reason (R): It produces clusters in which the membranes of individual fat globules join each other, although the fat itself is not in contact.
In light of the above statements, choose the most appropriate answer from the options given below.

• A. Both (A) and (R) are correct and (R) is the correct explanation of (A).
• B. Both (A) and (R) are correct but (R) is NOT the correct explanation of (A).
• C. (A) is correct but (R) is not correct.
• D. (A) is not correct but (R) is correct.

Hint:

Remember the role of the two stages in homogenization: {Stage 1} (high pressure) breaks the fat globules. {Stage 2} (low pressure) breaks the clusters formed after stage 1, preventing excessive viscosity increase.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
This question addresses the effect of single-stage homogenization on the physical properties of milk, specifically its viscosity, and the mechanism behind this effect.
Step 2: Detailed Explanation:
Analysis of Assertion (A): Homogenization is a process that breaks down large fat globules into much smaller ones. In a single-stage homogenizer, milk is forced at high pressure through a narrow valve. This breaks the fat globules, but the newly created fat surface area is vast, and there isn't enough natural membrane material (proteins, phospholipids) to cover it all immediately. As a result, the small, unprotected fat globules tend to stick together, forming large clumps or clusters. These clusters interfere with the flow of the liquid, causing a significant increase in viscosity. Thus, Assertion (A) is true.
Analysis of Reason (R): This statement describes the mechanism of cluster formation. The newly formed fat globules share the available protein membranes, leading to the formation of clusters where the individual globules are linked by these shared membranes. The fat inside each globule remains separate. This is an accurate description of the "fat clumping" phenomenon in single-stage homogenization. Thus, Reason (R) is true.
Relationship between (A) and (R): The formation of the fat globule clusters as described in (R) is the direct physical reason for the increase in viscosity stated in (A). Therefore, (R) is the correct explanation for (A).
Step 3: Final Answer:
Both Assertion (A) and Reason (R) are correct, and (R) correctly explains (A). (Note: This is why two-stage homogenizers are used; the second, lower-pressure stage breaks up these clusters).