The test detects the free carbonyl group (C=O) at the anomeric carbon of a reducing sugar. This group can be oxidized, thereby reducing the Cu²⁺ in Benedict's reagent to Cu⁺, forming a colored precipitate. Non-reducing sugars lack this free group.
The test detects the free carbonyl group (C=O) at the anomeric carbon of a reducing sugar. This group can be oxidized, thereby reducing the Cu²⁺ in Benedict's reagent to Cu⁺, forming a colored precipitate. Non-reducing sugars lack this free group.