Question

Homogenization serves to prevent the formation of which one of the following in the package during storage?

• A. Butter layer only
• B. Oil layer only
• C. Cream layer only
• D. Oil and butter layers

Hint:

Homogenization disrupts fat globules into sub-micron sizes, arresting creaming according to Stokes' law ($v \propto r^2$).

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Raw milk is a natural oil-in-water emulsion that undergoes spontaneous gravitational phase separation (creaming).

Step 2: Detailed Explanation:
According to Stokes' Law, the upward creaming velocity of fat globules is proportional to the square of the globule diameter ($v \propto r^2$).
High-pressure homogenization forces milk through a narrow orifice at $15\text{--}25\,\text{MPa}$, reducing fat globule diameter from $3\text{--}10\,\mu\text{m}$ to $< 2\,\mu\text{m}$.
This dramatic reduction in droplet size reduces the creaming velocity by over $95\%$, permanently preventing the formation of an unappealing cream layer (creaming plug) during storage.

Step 3: Final Answer:
Thus, homogenization serves to prevent the formation of the cream layer only.