Question

A non-reducing sugar "A" hydrolyses to give two reducing mono saccharides. Sugar A is :

• A. Glucose
• B. Fructose
• C. Galactose
• D. Sucrose

Hint:

Sucrose is the only common disaccharide that is non-reducing. Maltose and Lactose are reducing.

Answer 1

The Correct Option is D

Step 1: Monosaccharides like Glucose and Fructose are always reducing sugars.
Step 2: **Sucrose** is a disaccharide where the reducing groups of both Glucose ($C1$) and Fructose ($C2$) are involved in the glycosidic bond.
Step 3: Since no free aldehydic or ketonic group is available, Sucrose is **non-reducing**.
Step 4: Hydrolysis of Sucrose yields Glucose and Fructose, both of which are **reducing**.