Molecular and sensory studies on the umami taste of Japanese green tea.
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.
Kaneko
Shu
S
Material R & D Laboratory, Ogawa & Co. Ltd., Chidori 15-7, 279-0032, Urayasu, Chiba, Japan. kaneko.shu@ogawa.net
Kumazawa
Kenji
K
Masuda
Hideki
H
Henze
Andrea
A
Hofmann
Thomas
T
D002851:Chromatography, High Pressure Liquid; D005707:Gallic Acid / Q000032:analysis; D005971:Glutamates / Q000032:analysis; D006801:Humans; D007564:Japan; D009682:Magnetic Resonance Spectroscopy; D011208:Powders; D012970:Sodium Glutamate; D021241:Spectrometry, Mass, Electrospray Ionization; D019802:Succinic Acid / Q000032:analysis; D013649:Taste; D013662:Tea / Q000737:chemistry*
D005971:Glutamates; D011208:Powders; D013662:Tea; D005707:Gallic Acid; C026166:theanine; D019802:Succinic Acid; D012970:Sodium Glutamate