Wikipedia Article About Malt sugar on Wikipedia Maltose (also: malt sugar, di-glucose) is a disaccharide with the molecular formula C12H22O11. Its systematic name is α-D-Glucopyranosyl-(1→4)-α-D-Glucopyranose. Like other carbohydrates, maltose has a hydrogen to oxygen ratio of 2:1. It consists of two α-glucose molecules joined by a glycosidic bond between carbon atom 1 of the first glucose unit and carbon atom 4 of the second glucose unit. The second glucose unit is reducing, however the first one is not because the reducing group is part of the glycosidic bond.