Question

Colostrum has low heat stabilty due to its

• A. High sodium content
• B. High fat content
• C. High protein content
• D. Low sodium content

Hint:

The low heat stability of colostrum is caused by its high concentration of immunoglobulins (whey proteins), which denature and coagulate upon heating.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Colostrum is the first milk secreted by mammals in the days immediately following parturition.
Its composition differs from mature milk, as it is designed to provide immunoglobulins and nutrients to the newborn offspring.

Step 2: Detailed Explanation:
Colostrum contains high concentrations of proteins, particularly immunoglobulins (\(\text{IgG}\), \(\text{IgA}\), and \(\text{IgM}\)) and other whey proteins.
In first-milking colostrum, the total protein content can reach \(14\%\) to \(15\%\), compared to around \(2\%\) in mature milk.
These globulins are globular whey proteins that are highly sensitive to heat treatment.
When colostrum is heated to pasteurization or boiling temperatures, these proteins denature, unfold, and form intermolecular disulfide bonds.
This denaturation leads to rapid protein aggregation and coagulation, causing the colostrum to clot or gel.
While colostrum also has elevated mineral and fat levels compared to mature milk, the high concentration of heat-sensitive immunoglobulins is the primary cause of its low heat stability.

Step 3: Final Answer:
Therefore, colostrum has low heat stability due to its high protein content.