Abstract
An aroma extract of the headspace above infused sencha (1.8 kg) was prepared by using a purge-and-trap technique. In addition, the extract of infusion (100 L) was obtained by distillation under a reduced pressure before solvent extraction followed by application of a strong vacuum using the solvent-assisted flavor evaporation technique. Odorants in the volatile fractions from the aroma extracts were identified using mass spectrometry, or single ion mode detection, as well as odor quality and retention indices by means of two types of fused silica capillary columns DB-wax and DB-5MS. An aroma extract dilution analysis has revealed that (Z)-1,5-octadien-3-one (metallic-like), (E,Z)-2,6-nonadienal (green) and 3-methynonane-2,4-dione (green) were the most prevalent odorants in the headspace above infused sencha; while 2 odorants, namely, β-damascenone (sweet) and 4-hydroxy-2,5-dimethyl-3(2H)-furanone (sweet) were potent odorants present in the infusion.
