Question

Which of the following is non-reducing sugar?

• A. Maltose
• B. Lactose
• C. Sucrose
• D. Glucose

Hint:

If no free aldehyde or ketone group is present, the sugar is non-reducing.

Answer 1

The Correct Option is C

Step 1: Reducing sugars are those sugars which have a free aldehyde or ketone group capable of acting as a reducing agent.
Step 2: Maltose, lactose, and glucose possess a free reducing group and hence are reducing sugars.
Step 3: In sucrose, the glycosidic bond involves both the reducing ends of glucose and fructose, leaving no free reducing group. Therefore, sucrose is a non-reducing sugar.