Book Review

Chemistry and Applications of Green Tea

edited by Takehiko Yamamoto, Lekh Raj Juneja, Djoing-Chi Chu, Mujo Kim.

CRC Press LLC. Boca Raton, FL. 1997. 176 pages.
$74.95 Hard cover, ISBN 0-84934-006-3.
Buy this book now from Amazon.com
(Price/availability info may have changed since original publication of review.)

Reviewed by Jose Gallego (9/2000)

Many books describe the therapeutic properties of herbs. Most of them present testimonials empirically rather than using a scientific approach. Chemistry and Applications of Green Tea is the result of 10 years of scientific approach to many of the testimonials regarding the properties of the Green Tea.

For more than 1,000 years green tea has been used in Japan as a medicinal herb and as a refreshing after-meals drink. Over time, many therapeutic properties have been ascribed to it. This book focuses on the following:

At the beginning is an introduction to tea cultivation and the tea plant, a kind of evergreen laurel tree, Camellia sinensis, of the Theaceae family.

Then follows a description of processing leaves for green tea. In tea production, teas are classified according to their degree of fermentation. Green tea is unfermented, oolong tea is semi-fermented and black tea is fully fermented.

Green tea is classified into eight different products, depending on how the plant has been cultivated (more than 90 percent shading, 40-50 percent shading or non-shading), how it is harvested, if enzyme activation was used and the type of processing (drying, grinding and/or roasting). Of these, the Gyokuro is considered the highest quality and Bancha the lowest. Sencha is produced in larger quantity than any of the others, followed by Bancha and then by Matcha. Gyokuro represents only 0.4 percent of green tea production--the process is considered more art than manufacturing.

In listing the chemical composition of green tea, the book shows that reported concentrations are dependent mainly on the season the leaves are harvested, the condition of the soil and the process used for the final tea product. Compounds listed include polyphenols, caffeine, amino acids (including theanine), vitamins, inorganic elements, carbohydrates and lipids. This is organic chemistry at its best, showing how the polyphenols are separated and purified. Also described in detail is the analytical equipment used to detect and quantify teaís main components.

In the remaining chapters, empirical descriptions are brought into the laboratory and confirmed or denied. Here, scientists use modern analytical equipment (such as gas chromatography), experimental design and chemometrics (statistical methods for analysis of laboratory data). Unlike many other herb books, anecdotal statements are taken to the laboratory and tested under strict controls.

This book is an excellent source of information on using high technology and strict laboratory procedures to test empirical testimonials. It is gratifying to read a book that is neither selling you anything nor promising the miracle properties of an elixir; instead, this book presents facts.

As a side note, right after reading Chemistry and Applications of Green Tea I started drinking green tea on a regular basis. Okay, it is not the best tasting tea; polyphenols donít really taste good, you know; that is why I have been purchasing the tea with Jasmine flowers.


© Copyright 2000, California Rare Fruit Growers, Inc.
Questions or comments? Contact us.