It is composed of two molecules of monosaccharides, namely glucose and fructose. As both the functional groups (aldehyde and ketone groups) are involved in the formation of glycosidic linkage, there is no free reducing group. Hence, sucrose is known as a non-reducing sugar. The type of linkage in sucrose is α, β(1 → 2) glycosidic between C-1 of α-glucose and C-2 of β-fructose (Figure 2.11).