Question

Which of the following products has maximum content of phospholipids

• A. Cream
• B. Butter
• C. Butter oil
• D. Butter milk

Hint:

During the churning of cream into butter, the phase inversion from "oil-in-water" to "water-in-oil" occurs. This process releases the polar components of the milk fat globule membrane (MFGM), concentrating the phospholipids into the byproduct known as buttermilk.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
Phospholipids are polar lipids containing a hydrophobic tail and a hydrophilic head.
In milk, phospholipids are not located within the core of fat globules; instead, they are concentrated in the Milk Fat Globule Membrane (MFGM), which stabilizes the fat-in-water emulsion.

Step 2: Detailed Explanation:
Let us analyze the distribution of the Milk Fat Globule Membrane (MFGM) and its associated phospholipids during various processing stages of dairy products:
- Cream: Cream is an oil-in-water emulsion where fat globules are concentrated. While it contains a high absolute amount of fat, the phospholipids remain bound to the intact MFGM surrounding these globules.
- Butter: During the churning of cream to manufacture butter, the mechanical agitation ruptures the protective MFGM. This causes the liquid fat core to coalesce and form butter grains.
- Butter oil (Ghee): Butter oil is virtually pure fat (\(> 99.5\%\)), prepared by melting butter and removing moisture and SNF (solids-not-fat). The polar phospholipids are degraded or lost in the serum during heating.
- Butter milk: When the MFGM is physically disrupted during churning, the highly polar fragments of the ruptured membranes, including the hydrophilic phospholipids, are partitioned preferentially into the aqueous phase.
- This aqueous byproduct is buttermilk. Because it retains the majority of the ruptured MFGM material, buttermilk contains the highest proportion of phospholipids relative to its total lipid fraction.
Comparing all the options, buttermilk has the highest relative content of phospholipids.

Step 3: Final Answer:
The dairy product that contains the maximum relative content of phospholipids is butter milk.