From Plant Resources of South-East Asia No 13: Spices, PROSEA Foundation
by M. Flach and J. S. Siemonsma
Taxon
Cinnamomum verum J.S. Presl
Protologue
Prir. rostlin 2: 36—44. t. 7 (1825).
Family
LAURACEAE
Chromosome Numbers
2n = 24
Synonyms
Laurus cinnamomum L. (1753), Cinnamomum zeylanicum Blume (1826).
Vernacular Names
Ceylon
cinnamon, true cinnamon (En). Cannellier de Ceylon (Fr). Indonesia:
kayu manis. Malaysia: kayu manis. Papua New Guinea: skin diwai.
Philippines: cinnamon, kanela. Cambodia: che'k tum phka loëng.
Vietnam: qu[ees] h[oof]i, qu[ees] r[af]nh, qu[ees] Srilanca.
Origin and Geographic Distribution
Ceylon
cinnamon occurs wild in south-west India, western Sri Lanka and the
Tenasserim Hills of Burma (Myanmar). Cinnamon (and cassia) were among
the first spices sought after by most 15th and 16th Century European
explorers. The Portuguese, occupying Sri Lanka in 1536, and the Dutch,
taking over in 1656, established virtual monopolies on the trade. From
a product collected from wild stands, it became a cultivated crop in
Sri Lanka around 1770. It was introduced into the Seychelles in 1771,
where it easily naturalized and where a sizeable production developed.
Cultivation in Java (Indonesia) began in 1825 but, after initial
success, declined rapidly. Subsequently, Ceylon cinnamon has been taken
to many countries. It is grown in southern India, the Seychelles and in
Madagascar, but Sri Lanka continues to dominate the market.
Uses
The spice (Ceylon) cinnamon is the dried inner bark of Cinnamomum verum.
The major uses of cinnamon, both in whole and ground form, are for
domestic culinary purposes and for flavouring processed foods (bakery
products, sauces, pickles, puddings, beverages, confectionery), in
perfumes, pharmaceutical products and in incense. Cinnamon bark is an
important folk medicine. Cinnamon bark is astringent, stimulant and
carminative. It possesses the property of checking nausea and vomiting.
The
bark can further be used for the distillation of bark oil and for the
preparation of solvent-extracted oleoresin. The leaves are used for
distillation of leaf oil, which has a different composition than bark
oil.
The oleoresin is used mainly by the flavour industry in
western Europe and North America for flavouring processed foods and in
the soft-drink industry.
Cinnamon bark oil is used in flavouring
(processed foods, beverages, dental and pharmaceutical preparations),
much less in perfumery because it has some skin-sensitizing properties.
As a powerful local stimulant it is sometimes prescribed in
gastrodynia, flatulent colic and gastric debility. In European
phytomedicine, cinnamon bark oil (0.05-0.2 g daily intake) is used in
teas and other galenicals for its antibacterial, carminative, and
fungistatic properties, and also for loss of appetite and dyspeptic
disturbances. The maximum permitted level in food products is 0.06%.
Cinnamon
leaf oil is used in flavouring and perfumery, and as a source of its
major constituent eugenol. Eugenol is used for the synthesis of
vanillin, and for conversion into iso-eugenol, used for flavouring
confectionary products. Cinnamon leaf oil is extensively used as a
fragrance component in soaps, detergents, cosmetic and alcoholic
perfumery, with a maximum permitted level of 0.8% in the perfume.
In
the United States the regulatory status 'generally recognized as safe'
has been accorded to cinnamon (GRAS 2289), cinnamon bark oil (GRAS
2290/2291) and cinnamon leaf oil (GRAS 2292).
The seeds contain about 30% fixed oil, used in India for candle making. The oil is obtained by boiling crushed ripe fruits.
The
timber is light to moderately heavy (specific gravity 0.5-0.7), usually
straight-grained, even-textured, and weak. It seasons easily but warps,
splits, cracks and stains. It is suitable only as low-grade board wood.
Production and International Trade
Sri
Lanka produces the largest quantity and the best quality of bark of
Ceylon cinnamon, mainly as quills. Total harvested areas in 1998 were
estimated by FAO at 24,000 ha in Sri Lanka and 3400 ha in the
Seychelles, producing respectively 12,000 t and 600 t. Exports are
about 6,000 t annually. Most cinnamon leaf oil also originates from
these countries, whereas cinnamon bark oil and oleoresin are mainly
prepared in the importing countries. From 1987-1992, Sri Lanka exported
annually less than 3 t of bark oil, and about 115 t of leaf oil. The
United States and western Europe are the main markets for these oils.
Cinnamon bark oil is very expensive (1993: US$ 385/kg), reflecting the
high raw material cost. Cinnamon leaf oil is much cheaper (1994: US$
8.25/kg), but still more expensive than clove leaf oil (1994: US$
2.70/kg), an alternative source of eugenol.
Properties
The
dried inner bark of Ceylon cinnamon contains a steam-volatile oil,
fixed oil, tannin, resin, proteins, cellulose, pentosans, mucilage,
starch, calcium oxalate and minerals. The organoleptic properties are
determined by the steam-volatile oil and the trace amounts of coumarin
(non-steam-volatile). The essential-oil content of the bark varies from
0.5-2.0%.
Cinnamon oleoresin is a deep reddish or greenish brown
viscous liquid, and contains the steam-volatile oil (16-65%), fixed
oil, and other components dependent on the solvent. Ceylon cinnamon
bark yields 10-12% oleoresin with ethanol as solvent, compared with
2.5-4.3% with benzene.
It is phytochemically interesting that
the same tree produces 3 quite distinct essential oils, characterized
by eugenol in the leaves, cinnamaldehyde in stem bark, and camphor in
root bark.
Cinnamon bark oil is a pale-yellow liquid. Apart from
50-75% cinnamaldehyde, the important components (> 1%) include
eugenol (5-18%), cinnamyl acetate, linalool, 1,8-cineole,
'BETA'-caryophyllene, and benzyl benzoate. The powerful characteristic
note might be due to methyl-n-amylketone in combination with other
aldehydes and ketones. Oil from bark chips is richer in eugenol
(30-38%) and poorer in cinnamaldehyde (44%). Cinnamaldehyde is
anesthetic, antipyretic, hypotensive, hypothermic and sedative.
Cinnamon
leaves contain 0.7-1.2% essential oil. The leaf oil is yellow to
brownish-yellow in colour. In composition it is more like clove oil.
Apart from 70-95% eugenol (ISO: 75-85% phenols), important components
(> 1%) include cinnamaldehyde (ISO: < 5%), benzyl benzoate,
linalool, and 'BETA'-caryophyllene. Cinnamon leaf oil is of special
interest for its antioxidant and antibacterial properties. Eugenol is
strongly antiseptic.
Cinnamon root bark contains 1-2.8 % of a
colourless to pale yellowish-brown oil, which has no commercial
importance. The major component is camphor (60%), which crystallizes on
standing.
Monographs on the physiological properties of cinnamon
bark oil and cinnamon leaf oil have been published by the Research
Institute for Fragrance Materials (RIFM).
Adulterations and Substitutes
Cinnamon
and cassia barks are interchangeable in many applications, and the same
applies to cinnamon bark oil, cassia bark oils and (Chinese) cassia
leaf oil. Adulteration with synthetic cinnamaldehyde is simple and
mainly a function of the price of the natural product. However,
detection methods have much improved, and adulteration is becoming less
common.
As a source of eugenol, cinnamon leaf oil has lost ground to
the cheaper clove leaf oil, except when the eugenol is needed for
conversion into iso-eugenol (used in confectionary products).
Botany
Evergreen
tree up to 18 m tall; bole low-branching, up to 60 cm in diameter;
buttresses 60 cm tall, 70 cm deep, thin, light pinkish-brown; bark
about 10 mm thick, strongly aromatic; the bark on young shoots is
smooth and pale brown, on mature branches and stems rough, dark brown
or brownish-grey; oil cells are located in the phloem, and are oval or
round in cross- section; wood of mature trees varies from light
brownish-grey to grey or yellowish-brown, without markings, more or
less lustrous and faintly scented. Leaves opposite, somewhat variable
in form and size, strongly aromatic; petiole 1-2 cm long, grooved on
upper surface; blade ovate to elliptical, 5-25 cm x 3-10 cm,
conspicously 3-veined, or 5-veined, base rounded, apex acuminate,
glabrous, coriaceceous, shiny dark green. Inflorescence consisting of
lax axillary or terminal panicles up to 10 cm long or longer; peduncle
creamy white, softly hairy, 5-7 cm long; flowers small, 3 mm in
diameter, with foetid smell, pale yellow, subtended by small ovate
hairy bract; perianth 8 mm long, silky hairy, with short campanulate
tube and 6 persistent tepals about 3 mm long; fertile stamens 9, in 3
whorls, with 2 small glands at the base of the stamens of the 3rd
whorl; a fourth innermost whorl consists of 3 staminodes; filaments
hairy, stout; anthers 4- or 2-celled; ovary superior, 1-celled, with a
single ovule, style short. Fruit a 1-seeded berry, ellipsoidal to
ovoid, 1-2 cm long, black when ripe, surrounded by the enlarged
perianth at the base.
Growth and Development
Ceylon
cinnamon produces moderately deep and extensive roots. Seedling root
growth is initially rapid, with formation of a well-developed taproot
followed by numerous spreading laterals. There is normally a single
central stem, but in cultivation trees are coppiced. The uncut tree has
numerous, often drooping, branches beginning low on the trunk. Growth
takes place in flushes, young leaves being reddish in colour, later
turning dark green. Pollination is most probably by insects, especially
flies. Fruits mature in 6 months.
Other Botanical Information
In
Sri Lanka several wild and semi-wild types and local cultivars are
recognized, with distinctive local names. Distinction is mainly based
on aroma and therefore location-specific.
Ecology
Ceylon
cinnamon requires a warm and per-humid climate with a well-distributed
annual rainfall of 2000-2500 mm, and average temperatures of about
27°C. It grows best at low altitudes, and is usually grown without
shade, but being essentially a forest tree, light shade does no harm.
The type of soil has a pronounced effect on bark quality. Fine sandy
and lateritic gravelly soils rather than rocky and stony substrates are
best in Sri Lanka and India, but in the Seychelles and Madagascar more
loamy soils are preferred. Ceylon cinnamon is considered susceptible to
salinity. A bitter product results from waterlogged and marshy
conditions.
Propagation and planting
Propagation
is by seed or by vegetative means. Fruits are much liked by birds and
the seed is easily spread, so the fruits have to be bagged for
collection. Fruit pulp is allowed to rot before seeds are removed,
washed and dried. Seeds quickly lose their viability. Fresh seeds
germinate in 20-25 days. They are sown in nurseries or directly in the
field. The nursery bed (1 m wide) should have a well-prepared rich
sandy soil and be lightly shaded. Seeds are sown close together. Clumps
of seedlings are transferred into bags after 4 months in the nursery
and transplanted to the field after another 4-5 months. Five or more
seedlings are always planted closely together in a small circle,
developing into an indiscriminate clump.
Vegetative propagation is
by cuttings, layering or division of old rootstocks. Young cuttings
with 2-3 nodes are planted in polybags and placed under polythene
cover; they are ready for field planting after 12-18 months. Old
rootstocks can be divided. For this, old plants are cut down to within
15 cm of the ground, and suitable parts of the rootstock planted out
with adhering soil. Harvesting can start 1-1.5 years after planting out
in the field compared with 3 years for seedlings. Modern
micropropagation methods have also been successfully applied to produce
large numbers of plantlets.
Field spacings of 0.9-1.2 m x 0.9-1.2 m
are recommended in Sri Lanka for commercial plantations, but wider
planting up to 3 m x 3 m is also practised with a higher number of
plants per clump.
Husbandry
After-planting
care mainly consists of weeding, 2-4 times a year. Stems are kept
straight by pruning. Manure or plant residues are commonly applied as
fertilizer, but chemical fertilizers, although recommended, are little
used. Placing phosphate in the planting holes is advantageous, single
superphosphate being preferable because of the small amounts of sulphur
it contains. Annual application of a 2 : 1.5 : 1.5 mixture of urea,
rock phosphate and potassium chloride is recommended at a rate of 40-60
kg/ha to young trees, and 100 kg/ha to mature trees. A nitrogenous top
dressing at the beginning of the rainy season is advisable for quick
(re)growth of (coppiced) trees. It is advisable to return processing
residues to the field as mulch. Plants are coppiced for the first time
after 2 years, the stem being cut to within 10-15 cm from the ground
and covered with earth, allowing 4-6 shoots per stool to grow for a
further 2 years before harvesting. After harvesting, all unwanted
shoots and stumps are cut off the stool, which is then covered with
earth, and new shoots are allowed to grow. The number of shoots per
stool normally increases to a maximum at 8 years and declines after
10-12 years. A cinnamon plantation can remain profitable for 15-45
years, mainly depending on the standard of management.
Diseases and Pests
Stripe canker (Phytophthora cinnamomi)
may damage trunks and branches of young trees in particular. Symptoms
are vertical strips of dead bark, particularly near ground level. Root
rots include black rot caused by Rosellinia spp., brown rot by Phellinus lamaensis, and white rot by Fomes lignosus. Pink disease (Corticium salmonicolor, syn. Corticium javanicum) causes pink encrustations on the stem with death of small shoots. Glomerella cingulata causes anthracnose. Rust (Aecidium cinnamomi) and other leaf and stem diseases (Cephaleuros virescens, Diplodia spp., Exobasidium spp., Gloeosporium spp., Leptosphaeria spp., Pestalotia cinnamomi) may occasionally cause damage.
In India and Sri Lanka, caterpillars of the cinnamon butterfly (Chilasa clytia) are destructive to new flushes, and shothole borers (Xylosandrus spp.) cause damage to stem and bark. Leaf miners (Acrocercops spp., Phyllocnistis chrysophthalma), gall and leaf mites (Eriophyes bois, Eriophyes doctersi, Typhlodromus spp.), leaf webbers (Sorolopha archimedias) and arboreal ants (Oecophylla smaragdina) cause occasional damage. Young seedlings are vulnerable to damage by agrotid larvae or mole crickets (Gryllotalpa spp.), and larvae of Popillia spp., attacking roots. Ceylon cinnamon is also attacked by root-knot nematodes (Meloidogyne spp.). Storage pests of cinnamon quills include Lasioderma serricorne, Pyralis farinalis and Sitodrepa panicea.
Harvesting
Ceylon
cinnamon has to be harvested during the wet season because then the
cambium is active and the cortex can be easily separated from the wood.
The shoots are harvested when they are 2-3 m tall and 1.2-5.0 cm in
diameter. Shoots in the centre of the clump are cut low down, while
those on the outside are cut higher up to ensure that new buds sprout
mainly on the outside of the clump. In Sri Lanka harvest peaks are in
May-June and October-November. The first harvest is of inferior quality
(thick bark), but this improves in later harvests. Best quality
cinnamon is obtained from thin bark from the middle part of shoots in
the centre of the stool. Leaves and twigs are cut off and used for
mulching, or the leaves are retained for distillation. The harvested
shoots are bundled and taken to a processing unit for peeling and
further preparation.
Yield
The
first crop, 3-4 years after planting, yields 50-120 kg/ha of quills,
increasing in subsequent crops to 175-250 kg/ha, before yields decline
after 10-12 years. Commercial cinnamon bark is not more than 0.5 cm
thick and is of a dull pale brown colour. The inner surface is somewhat
darker than the outer one and is finely striated longitudinally.
By-products of the production of quills are cinnamon chips (averaging
60 kg/ha) and leaves (2.5 t/ha fresh weight). Large individual trees
may yield up to 45 kg of dry bark. Average annual bark yields of 120
kg/ha have been reported for the Seychelles, and an annual yield of
fresh leaves of about 1.9 t/ha, yielding 0.6-0.8% leaf oil (11-16
kg/ha). Leaf-oil yields of 35-40 kg/ha have also been reported.
Handling After Harvest
Peeling
consists of stripping the bark for the preparation of quills from the
inner bark. The outer bark is first removed and the stem then rubbed to
loosen the inner bark. Two horizontal cuts are made 30 cm apart and two
longitudinal slits on opposite sides of the shoot. The inner bark is
then separated from the wood. Alternatively, the outer and inner bark
are separated from the wood together. The strips are packed together,
wrapped and left overnight for slight fermentation, facilitating the
subsequent scraping off of the outer bark (epidermis, cork and green
cortex). The curled pieces are assembled into compound quills of 1 m
length by joining the best and longest quills on the outside and
smaller pieces inside the longer ones. They are dried in the shade
until they are yellowish-brown. They are sometimes bleached by sulphur
treatment. The grading of Ceylon cinnamon is rather elaborate compared
with the grading of cinnamon from other sources. The various forms and
qualities are known as unscraped bark, scraped bark, compound quills,
simple quills, quillings (broken pieces of quills), featherings (bark
of twigs and twisted shoots) and chips (trimmings, shavings). Quills
are further graded according to the thickness of the bark. Grinding
usually takes place in the consuming countries.
Bark to be
distilled for oil should not be allowed to become damp, as this
encourages mould or fermentation, which affects oil composition. Bark
oil is obtained by steam or hydro-distillation with cohobation, or
solvent extraction of the distillate. Solvent extraction of the
distillate gives the finest quality oil.
Leaves stripped from
shoots, together with small leafy twigs and stems are left in the field
for 3-4 days and then transported to the distillery.
Root bark oil
is only produced when a plantation is uprooted for replanting. Roots
are cleaned, trimmed and peeled prior to distilling.
Genetic Resources and Breeding
There are no germplasm collections of Cinnamomum verum. Little improvement work has been done. Since Cinnamomum
is open-pollinated, selection, together with vegetative propagation of
clonal material would be advantageous. Some selection for superior
strains is carried out in Sri Lanka and the Seychelles.
Prospects
The
demand for the spice cinnamon (and cassia) has always been
satisfactory, and the prospects are still promising, as the competition
from synthetic alternatives does not noticeably affect the trade.
Consumption is likely to be mainly a function of population growth. The
prospects for the essential oils seem to be less bright, as there are
many alternatives.
Literature
Coppen, J.J.W., 1995. Flavours and fragrances of plant origin. Non-wood Forest Products 1. FAO, Rome, Italy. pp. 7-17.
Kostermans,
A.J.G.H., 1995. Lauraceae. In: Dassanayake, M.D., Fosberg, F.R. &
Clayton, W.D. (Editors): A revised handbook to the Flora of Ceylon.
Vol. 9. Amerind Publishing Co., New Delhi, India. pp. 112-115.
Purseglove,
J.W., Brown, E.G., Green, C.L. & Robbins, S.R.J., 1981. Spices.
Vol. 1. Longman, Harlow, Essex, United Kingdom. pp. 100-173.
Richard,
H.M.J., 1991. Spices and condiments I. In: Maarse, H. (Editor):
Volatile compounds in foods and beverages. Marcel Dekker, New York,
United States. pp. 411-447.
The Wealth of India (various editors),
1948-1976. A dictionary of Indian raw materials and industrial
products: raw materials. Vol. 2. Publications and Information
Directorate, Council of Scientific and Industrial Research, New Delhi,
India. pp. 179-183.
Weiss, E.A., 1997. Essential oil crops. CAB International, Wallingford, Oxon, United Kingdom. pp. 180-195.
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