Raffinose is a trisaccharide carbohydrate that is used as a bulking agent, blood substitute, stabilizing agent, and water scavenger in freeze-drying where it acts as a stabilizer for freeze-dried formulations. It is also used as a crystallization inhibitor in sucrose solutions.
Raffinose can be hydrolyzed to sucrose and galactose by the enzyme α-galactosidase (α-GAL). Humans do not possess the α-GAL enzyme in their small intestine to break down the trisaccharide.
Raffinose family of oligosaccharides (RFOs) are α-1, 6-galactosyl extensions of sucrose (Suc). This group of oligosaccharides is found in plants and is known to serve as desiccation protectant in seeds, as transport sugar in phloem sap and as storage sugars.