| Abstract
| - Twenty-six synthetic glycosides constituting aglycons of the main tea aroma compounds ((Z)-3-hexenol, benzyl alcohol, 2-phenylethanol, methyl salicylate, geraniol, linalool, and four isomers oflinalool oxides) were synthesized in our laboratory as authentic compounds. Those compounds wereused to carry out a direct qualitative and quantitative determination of the glycosides as aromaprecursors in different tea cultivars by capillary gas chromatographic−mass spectrometric (GC−MS) analyses after trifluoroacetyl conversion of the tea glycosidic fractions. Eleven β-d-glucopyranosides, 10 β-primeverosides (6-O-β-d-xylopyranosyl-β-d-glucopyranoside) with aglycons as the abovealcohols, and geranyl β-vicianoside (6-O-α-l-arabinopyranosyl-β-d-glucopyranoside) were identified(tentatively identified in the case of methyl salicylate β-primeveroside) in fresh tea leaves andquantified on the basis of calibration curves that had been established by using the syntheticcompounds. Primeverosides were more abundant than glucosides in each cultivar we investigatedfor making green tea, oolong tea, and black tea. Separation of the diastereoisomers of linalool andfour isomers of linalool oxides by GC analyses is also discussed. Keywords: Tea aroma formation; aroma precursor; primeveroside; glucoside; glycoside of linalooloxide
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