Kojibiose, a disaccharide product of glucose caramelization and an inhibitor of plant glucosidase I, may be used to help identify and characterize glucosidase I enzymes involved in terminal deglycosylation of high-mannose oligosaccharides.Kojibiose may be used as a substrate to study the biological species, enzymes and catabolic processes that catabolize it as an energy source. Kojibiose may be used to identify, differentiate and characterize kojibiose phosphorylase(s) (KP).