Question

How is fructose considered as reducing sugar?

Answer 1

Fructose is considered as reducing sugar through the following points:

• A sugar considered as reducing which can be can be oxidized by a weak oxidizing agent such as Tollen's reagent (capable of oxidizing aldehydes, not alcohol) under a basic aqueous solution.
• Fructose doesn't contain any aldehyde group but it can reduce such reagents.
• This is due to the reason that the reagents are basic solutions, hence fructose can be isomerized to distinct aldoses( glucose and mannose).