Identification of potent odorants in different green tea varieties using flavor dilution technique

Two kinds of pan fired green teas (Japanese Kamairi cha and Chinese Longing tea) were compared with the common Japanese green tea (Sen cha) Application of the aroma extract dilution analysis (AEDA) using the volatile fraction of the Sen-cha, Kamain cha and Longing tea infusions revealed 32, 51, and 52 odor active peaks with flavor dilution factors between 16 and 1024 respectively (Z) 1 5-Octadien 3 one (metallic, geranium like) 4 mercapto 4-methyl 2 pentanone (meaty black currant like), methional (potato like) (E Z) 2,6 nonadienal (cucumber-like) and 3 methylnonane 2,4 dione (green fruity hay like) showed high flavor dilution factors in all varieties In addition 2 acetyl-1 pyrroline (popcorn like) 2 ethyl 3 5 dimethylpyrazine (nutty) 2 3 diethyl 5 methylpyrazine (nutty) and 2 acetyl-2-thiazoline (popcorn like) belonged to the most potent odorants only in the pan fired green teas Among these odorants 2 acetyl 1 pyrroline and 2 acetyl 2 thiazoline were identified for the first time among the tea volatiles.