カラメルの研究 第2報 : ショ糖の熱分解による少糖類の生成

Sucrose was pyrolyzed in the open air at 190± 5° to 12% weight loss and the residue extracted with 84% hot ethanol. The caramel obtained by concentrating this extract was submitted to carbon-Celite column chromatography and the fractions of 0-5.0% ethanol eluates analyzed for the constituents by means of paper and thin-layer chromatographies. Glucose and fructose were found to be present, the fact indicating that a part of sucrose was hydrolyzed during the pyrolysis. Levoglucosan and the three α-gluco-disaccharides of isomaltose, kojibiose and nigerose were identified by chromatographies and conversion into the acetates. Color reactions revealed presence of a few ketose-containing substances, beside undecomposed sucrose, and a number of unreducing substances, some of which were proved to be anhydro-disaccharides made of glucose and an anhydrosugar.