Question

In over-ripe fruit, pectin is converted into

• A. Pectinic acid
• B. Pectic acid
• C. Protopectin
• D. Gastric acid

Hint:

Protopectin (unripe) $\to$ Pectin/Pectinic acid (ripe, gel-forming) $\to$ Pectic acid (over-ripe, non-gelling).

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Pectic polysaccharides undergo sequential enzymatic modifications during fruit development, ripening, and senescence.

Step 2: Detailed Explanation:
The maturation pathway of pectic substances proceeds as follows:
1. Unripe fruit: Water-insoluble protopectin predominates, conferring rigid firmness.
2. Ripe fruit: Protopectin is hydrolyzed into water-soluble pectin (pectinic acid, methylated polygalacturonan) which possesses jelly-forming ability.
3. Over-ripe fruit: Pectinesterase and polygalacturonase de-esterify and hydrolyze pectin into completely demethylated pectic acid, which cannot form gels and results in tissue softening.

Step 3: Final Answer:
Hence, in over-ripe fruit, pectin is converted into pectic acid.