MAILLARD REACTIONS OF LACTOSE AND MALTOSE

Maillard type reactions of disaccharides with 1,4-glycosidic linkage have been investigated. When lactose is heated with a primary amine in nearly neutral aqueous solution, the beta-pyranone 5b, the cyclopentenone 7b, and the isomaltol derivative 8b are obtained as main products. The disaccharide-derived degradation products 5b, 7b, and 8b react further with primary amines to give pyrroles of type 10b, furanones 12, pyridinium betaines 9b, pyridones 13b, and 14, and pyridoneimines 11, respectively. Analogous products are obtained from maltose. Modeling side-chain reactions of proteins, these investigations were carried out with several primary amines, in particular with propylamine and alpha-N-acetyllysine.