Taste-guided fractionation and instrumental analysis of hydrophobic compounds in sake

Biosci Biotechnol Biochem. 2012;76(7):1291-5. doi: 10.1271/bbb.120046. Epub 2012 Jul 7.

Abstract

The taste-active hydrophobic compounds in a charcoal-untreated sake sample were subjected to a taste dilution analysis (TDA). All of the high-TDA factor fractions showed a bitter or astringent taste in common, but their taste characters were different. The taste-active compounds of the high-TDA factor fractions were purified by taste-guided fractionation, using RP-HPLC and an instrumental analysis. From each of the seven fractions, ferulic acid, ethyl ferulate, tryptophol, three previously reported bitter-tasting peptides, and two novel ethyl esters of the peptides of 10 amino acid residues were identified. All the identified compounds had a similar taste character to that of the TDA fractions analyzed. Ethyl ferulate and the ethyl ester of the peptides showed a moderately bitter taste. The concentration of the identified compounds in seven jyunmai-type sake samples was determined. This concentration was decreased dose dependently by a charcoal treatment which is commonly applied in the final step of sake manufacture, notably with the compounds of high hydrophobicity.

MeSH terms

  • Alcoholic Beverages / analysis*
  • Caffeic Acids / analysis
  • Charcoal / chemistry
  • Chemical Fractionation
  • Chromatography, High Pressure Liquid
  • Chromatography, Reverse-Phase
  • Coumaric Acids / analysis
  • Esters
  • Hydrophobic and Hydrophilic Interactions
  • Indoles / analysis
  • Magnetic Resonance Spectroscopy
  • Mass Spectrometry
  • Peptides / analysis
  • Taste

Substances

  • Caffeic Acids
  • Coumaric Acids
  • Esters
  • Indoles
  • Peptides
  • Charcoal
  • tryptophol
  • ethyl ferulate
  • ferulic acid