Effects of Glycosides on the Structure of Water-ethanol Mixtures

Abstract

NMR and DSC measurments were employed to discuss the structural change of water-ethanol mixtures.
Freshly mixed 50wt% of ethanol solution was compared with that of aged for 4 years in a European oak barrel. After aging, the line width at half height of water oxygen signal became narrow on the ¹⁷O-NMR and the hydroxy groups of water and ethanol appeared as coalescent signal on ¹H-NMR measurment. On DSC measurments, exothermal peak at about -50°C which ascribed to the melting of strongly interacted water and ethanol became extremely increased. And further observation on the effects of some glycoside derivatives on the structure of water-ethanol solutions were discussed. In these studies, just adding ethyl β-D-glucopyranoside showed the similar patterns both on NMR spectra and DSC thermogram with those of after aging solution in the barrel. These results are suggested that ethyl β-D-glucopyranoside promotes to change the structure of water-ethanol solution to that of after aging one.