Aroma of Tea

• Published in: Journal of Japan Association on Odor Environment Vol. 38; no. 3; pp. 179 - 186
• Main Author: SAWAI, Yusuke
• Format: Journal Article
• Language: English; Japanese
• Published: Tokyo Japan Association on Odor Environment 2007; Japan Science and Technology Agency
• Subjects: (Z)-3-hexenol; 2, 5-dimethylpyrazine; dimethyl sulfide; geraniol; linalool
• ISSN: 1348-2904; 1349-7847
• DOI: 10.2171/jao.38.179

The aroma of green tea contains fresh and flowery notes, and roast notes. Fleshy and greenish odor notes represent the typical aroma of green tea. The fleshy and greenish aroma is composed of (Z)-3-hexenol, (E)-2-hexenol, nonanal and (Z)-3-hexenyl hexanoate. Japanese green teas are heated after production so that Japanese green tea has roast aroma. Roast aroma is produced by pyrazines. Such compounds are formed by action of heat on the free amino acids and sugars in tea leaves during drying. The most important roast aroma compounds of green tea is 2, 5-dimethylpyrazine. Monoterpene alcohols (linalool and geraniol, etc.) are known to be the major floral tea aroma constituents, especially oolong and black tea. These alcohols, which have flowery and fruity aromas, are liberated from glucosides which accumulate in tea shoots. Gyokuro and Ceremony tea have a special aroma, originally called the rice-straw smell because it is produced by shading tea plants with rice-straw. It has been shown that the Gyokuro odor is associated with dimethyl sulfide which is formed during processing by thermal degradation of S-metyl methionine.