Question

Which of the following is an example of soluble fibre?

• A. Cellulose
• B. Hemicellulose
• C. Lignin
• D. Pectin

Hint:

Remember: Soluble fibers like pectin and gums form gels (think of fruit jams), while structural cell wall fibers like cellulose, hemicellulose, and lignin are insoluble.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
Dietary fibers are non-digestible carbohydrates and lignin found in plant foods, classified into soluble and insoluble categories based on their physical property of water solubility.

Step 2: Detailed Explanation:
Let us categorize the plant fiber components:

• Insoluble Fiber: Does not dissolve in water. It includes cellulose, hemicellulose, and lignin. These compounds add bulk to the stool and facilitate laxation.

• Soluble Fiber: Dissolves or swells in water, forming a viscous, gel-like substance. It is highly fermentable by colonic bacteria. Examples include pectin, gums, mucilages, and beta-glucans.
Among the given options, pectin is a soluble fiber commonly found in the cell walls of fruits like apples and citrus fruits, where it is used as a gelling agent.

Step 3: Final Answer
Pectin is an example of a soluble fiber.