Molecular and sensory studies on the umami taste of Japanese green tea

J Agric Food Chem. 2006 Apr 5;54(7):2688-94. doi: 10.1021/jf0525232.

Abstract

Aimed at defining the key drivers for the quality-determining umami taste of a high-grade powdered green tea, called mat-cha, a bioactivity-guided fractionation using solvent extraction, solvent precipitation, preparative chromatographic separations, and human psychophysical experiments was applied on freshly prepared mat-cha. Liquid chromatography-tandem mass spectrometry and one-/two-dimensional nuclear magnetic resonance studies on isolated fractions led to the identification of l-theanine, succinic acid, 3,4,5-trihydroxybenzoic acid (gallic acid), and (1R,2R,3R,5S)-5-carboxy-2,3,5-trihydroxycyclohexyl-3,4,5-trihydroxybenzoate (theogallin) as umami-enhancing compounds in the green tea beverage, and it can be shown by sensory studies that these compounds are able to raise the umami intensity of sodium l-glutamate proportionally.

MeSH terms

  • Chromatography, High Pressure Liquid
  • Gallic Acid / analysis
  • Glutamates / analysis
  • Humans
  • Japan
  • Magnetic Resonance Spectroscopy
  • Powders
  • Sodium Glutamate
  • Spectrometry, Mass, Electrospray Ionization
  • Succinic Acid / analysis
  • Taste*
  • Tea / chemistry*

Substances

  • Glutamates
  • Powders
  • Tea
  • Gallic Acid
  • theanine
  • Succinic Acid
  • Sodium Glutamate