alpha-santalol
beta-santalol
Sandalwood
Santalum album (Santalaceae) Indian sandalwood, White sandalwood
Santalum album is a medium-sized evergreen tree with opposite,
leathery leaves. It is found in tropical Asia through Australia to Hawaii.
Like most species of the genus Santalum it is a root parasite,
tapping the roots of other species for water and inorganic nutrients (the
mistletoe, Viscum album, parasiting braches of different trees,
is a relative). The wood of S. album is highly aromatic. The
light sapwood is used for wood carvings, whereas the darker wood from
the core is steam distilled, yielding the precious sandalwood oil. Bits
and pieces are used for incense sticks, etc. One of the most famous sites
of cultivation is Mysore in India. The trees must be 30 years before the
oil production pays off. The yield is not more than 5 %. Freshly distilled
sandalwood oil has a wonderful odour - an extremely soft, sweet-woody
and delicately animal-balsamic odour. For thousands of years it has been
one of perfumery's most precious items. It forms the basis of heavy Oriental
compositions, and creates delightful combinations with rose,
violet, tuberose,
clove, bergamot,
lavender and a lot
of other fragrant materials.
Sandalwood oil mainly consists of a number of closely related sesquiterpenoids.
Alpha-santalol and beta-santalol amount to more than 90 % of the oil,
beta-santalol beeing the most important character impact compound.
Müller and Lamparsky (1991) describe the odour of the two isomers
like this:
alpha-santalol - "A relatively weak, slightly woody odour reminiscent
of alpha-cedrene."
beta-santalol - "Typical sandalwood odour, with powerful woody, milky
and urinous tonalities." [5] [6]
beta-Santalol was synthesized in the laboratory for the first time in 1990 by an 11-step synthesis, a process completely unrealistic on an industrial scale. Today, the finest substitutes are derived from campholenic aldehyde, for instance Santaliff ®, produced by IFF (International Flavours & Fragrances Inc.). Javanol ®, by Givaudan, is a new 'cyclomethylene analogue' of this compound. It turns out that substituting the alkene double bonds with the almost isosteric cyclopropane rings creates increased olfactory power and stability. Javanol ® has a strongly diffusive, natural, creamy sandalwood note with rosy shadings. Interestingly, 3,7-dimethyl-7-methoxy-2-octanol also has a fine (but weaker) sandalwood character. It was formerly produced by Bush Boake Allen under the name of Osyrol ® (Osyris is another genus of the sandalwood family).
beta-santalol
(rotated to facilitate comparison)
Santaliff ®
Javanol ®
Osyrol ®
geraniol, citronellal, linalool, methyl cinnamate, and the alpha-sanshools
Zanthoxylum piperitum (Z. sansho) (Rutaceae) Sichuan pepper, Prickly ash
The Zanthoxylums are small, mostly deciduous trees of the Rutacean family. They are found in warm temperate and subtropical areas worldwide. The dried, brownish fruit walls (pericarps) of a number of species (Z. piperitum,
Z. simulans, Z. schinifolium, Z. alatum, etc.) are used as a spice in Asia and sometimes called the 3'rd pepper, next to black pepper and chili pepper.
Z. piperitum is widely used in Japan, China and Korea as a spice for its flavour and special pungency.
Not only the dried pericarps (photo) are used, the fresh young leaves, for example, are used as a topping on dishes.
Geraniol, citronellal, linalool and methyl cinnamate are found to be important flavour compounds in the dried pericarps by aroma extract dilution analysis [160].
The pungency of the Zanthoxylum peppers is due to alkamides derived from polyunsaturated carboxylic acids, mainly alpha-sanshool (N-isobutyl (2E, 6Z, 8E, 10E)-dodecatetraenoic amide) and hydroxy-alpha-sanshool. They are considerably less potent than capsaicin from chili and shows another sensory modality. The sanshools cause not only a burning sensation ("piri piri" in Japanese), but also a tingling one ("hiri hiri" in Japanese), and definitely also a numbing sensation at high levels [161].
Etymology: Chi. shanjiao, mountain pepper; Sichuan, a province in the central-western China; Gr. xanthon xylon, yellow wood; Eng. prickly ash, the leaves superficially resemble those of ash, but the branches are thorny.
lenthionine
Lentinus edodes (Pleurotaceae)
Shiitake is a popular edible mushroom from the Far East, for example served in miso soup. It is cultured on logs of the shii tree, Castanopsis (Querqus) cuspidata (Fagaceae), and exported in the dry state or pickled.
An important odoriferous principle of shiitake is 1,2,3,5,6-pentathiepane, called lenthionine. In the pure state it is a crystalline substance (m.p. 60 °C) [70].
-carvonePlus.gif)
(-)-carvone
and 2-acetyl-4-isopropenylpyridine
Spearmint
Mentha spicata (Labiatae) Native spearmint
Mentha cardiaca (Labiatae) Scotch spearmint
Botanical systematics is in trouble with the mint species because of the
multitude of varieties and crossings. Some 15 variable species may be
defined, all natives of Eurasia. They are fast-growing perennial herbs
with strongly odoriferous essential oils. Several of these are of great
economical importance.
Spearmint is characterized by its high level of (-)-carvone (> 50 %)
[97], perceivable at the slightest touch of the plant. The odour of spearmint
is rather different from that of peppermint.
A number of unusual pyridine derivatives have been identified in Scotch
spearmint oil, a major of these being 2-acetyl-4-isopropenylpyridine,
having a powerful grassy-sweet and minty odor [98].
Spearmint oil is extensively used in chewing gum, tooth paste, etc. One
of the worlds major production areas (ca. 1000 t/y) is the state of Washington
in USA [6].
P.S. The odour of (-)-carvone differs from that of (+)-carvone.
The odour of (-)-carvone is fresher, sweeter and much more diffusive.
-anethol.gif){kind=small}
(E)-anethole
shikimic acid
Star anise
Illicium verum (Illiciaceae) Chinese star anise
Chinese star anise is an evergreen bush of the magnolia order grown in
Vietnam and southern China. The ripe, strongly anise-smelling fruits open
up in a star. They are used as a spice, and for the production of star
anise oil by steam distillation.
Star anise oil is a colourless to pale yellow liquid which solidifies
on cooling. The main component (80-90 %) is
(E)-anethole [6]. Star anise oil, and (E)-anethole isolated from it, is
used in anise liqueur (Anisette, Sambuca) and anise brandy (Pernod, Ouzo,
Raki, Arak), liquorice sweets, tooth-paste, etc. It has almost completely
replaced the original anise
seed oil, obtained from the umbellifer Pimpinella anisum.
Shikimic acid, used in the production of the antiviral drug Tamiflu ®
(Roche), is extracted from the fruits of Chinese star anise and related
species [70].
The closely related Japanese star anise, I. anisatum, is highly toxic! It contains a poisonous sesquiterpene lactone, called anisatin, causing severe inflammation of the kidneys, urinary tract and digestive organs, as well as affecting the nervous system [99].
anisatin