Proton nuclear magnetic resonance and Raman spectroscopic studies of Japanese sake, an alcoholic beverage.

The hydrogen-bonding property of water--ethanol in Japanese sake, a kind of brewage, was examined on the basis of both (1)H NMR chemical shifts of the OH of water--ethanol and the Raman OH stretching spectra. In 20% (v/v) EtOH-H(2)O solution, amino acids as well as organic acids caused low-field chemical shifts, i.e.