Question

Type B gelatin is from an alkali treated precursor and has its isoelectric zone in the region of

• A. pH 9.0
• B. pH 4.7
• C. pH 7.0
• D. pH 1.2

Hint:

Remember: "A" for Acid-treated (higher pI) and "B" for Base/Alkali-treated (lower pI).

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Gelatin is derived from collagen. There are two main types of gelatin: Type A and Type B.
Type A is acid-processed, while Type B is alkali-processed.

Step 2: Detailed Explanation:
Alkali processing of collagen converts asparagine and glutamine residues into aspartic and glutamic acid.
This shift changes the net charge of the protein molecule.
Type B gelatin typically exhibits an isoelectric point (pI) in the acidic range, specifically between pH 4.7 and 5.2.
Type A gelatin generally has an isoelectric point in the range of pH 7.0 to 9.0.

Step 3: Final Answer:
The isoelectric zone of Type B gelatin is in the region of pH 4.7.