Question

Which of the following dietary fiber is insoluble in water ?

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

Answer 1

The Correct Option is B

In the context of dietary fibers, it's important to understand the solubility characteristics of each type. Dietary fibers are broadly classified into two categories based on their solubility in water: soluble and insoluble fibers.

Fiber Type	Solubility
Pectin	Soluble
Lignin	Insoluble
Hemicellulose	Partially Soluble
Cellulose	Insoluble

In the given options, we have:

• Pectin: Known as a soluble fiber, it dissolves in water.
• Lignin: This is an insoluble fiber, meaning it does not dissolve in water. It provides structural rigidity and is found in plant cell walls.
• Hemicellulose: Although part of it can be soluble, it's generally considered to have both soluble and insoluble fractions.
• Cellulose: This is another type of insoluble fiber. It adds bulk to the stool and aids in bowel movement.

From this, it's clear that the correct answer regarding insolubility is Lignin. This fiber remains undissolved in water, contributing to its role in maintaining digestive health by adding bulk to the diet.