II.Characteristics of A.A.R.(Agarwood)
Aquilaria agallocha Roxb. (A.A.R.) or agarwood is regarded as a pharmacological product formed as the result of a fungus disease caused by wounds or borings on the trunk. A.A.R. consists of irregular patches of dark wood highly charged with oleoresin, which is found in the interior of old trees. A.A.R. can be found in A.A.R trees aged from decades to hundreds of years. The A.A.R. tree belongs to Thymelaeaceae family. A.A.R. tree can grow up to 120 feet and live up to a thousand years. The disease takes more than 500 ~ 700 hundred years to form the highest concentration of oleoresin.
A.A.R. is found on the market in the form of chips, splinters and blocks. The most common sizes range from 7 to 30 cm long and 1.5 to 10 cm wide. However, some A.A.R. are longer than one meter. A.A.R. tastes slightly bitter, acrid, and fills with warm aromatic. It burns with bright flames and black smolders giving off a pleasant odor.
Unlike other kind of fragrant wood or material, A.A.R. does not generate obvious fragrance before burning. It only generates great fragrance when it is burned. The fragrance is effected by various factors such as level of containing oleoresin, reason of forming oleoresin and the color of resin.
A.A.R. oleoresin has five colors- green, dark green, golden (light yellow), yellow, and black. Green is regarded as the highest grade and black's grade is the lowest. Different color A.A.R. has different fragrance when it is burned.
The most important criterion to judge the grade of A.A.R. is its buoyancy. Chen-Xiang is the Chinese name of A.A.R. "Chen" means "sinking". The density of A.A.R. tree without oleoresin is a mere 0.4. However, when the percentage of containing oleoresin is over 25%, A.A.R. in any forms (chips, powders, or larger pieces) will sink into water. The Chinese name of A.A.R. is originated from this characteristic.
Because it takes so long to form a high quality A.A.R., the demand for A.A.R. is significantly greater than its supply. Although scientists and merchants in India and Indonesia had tried to cultivate A.A.R. with oleoresin in A.A.R. tree, it resulted in getting A.A.R. that contains very less oleoresin. In reality, it is almost impossible to find real A.A.R. in the market nowadays. Most A.A.R. sold in the market either is adulterated or can not be used as medicine because of its low content of oleoresin.
(1) 5 kinds
Reasons of forming
(2) Time frame
(1) Asia Vietnam, Malaysia, Thailand, Laos, Indonesia, India.