Amomum compactum (PROSEA)
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Introduction |
Amomum compactum Soland. ex Maton
- Protologue: Trans. Linn. Soc. 10: 251 (1811).
- Family: Zingiberaceae
- Chromosome number: 2n = 48
Synonyms
- Amomum cardamomum auct., non L. (1753),
- A. kepulaga Sprague & Burkill (1929).
Vernacular names
- Round cardamom, Java cardamom, false cardamom (En).
- Amome à grappe (Fr)
- Indonesia: kapulaga (Javanese), kapol (Sundanese), puwar pelaga (Sumatra)
- Malaysia: kepulaga, puar, pelaga
Origin and geographic distribution
A. compactum originates from and is an endemic of the lower hills of western Java. At present it is also cultivated in western Java, in southern Sumatra, in the Moluccas and occasionally elsewhere (e.g. in Singapore, Peninsular Malaysia, southern China).
Uses
The seeds of round cardamom have a peppery, ginger-like flavour and serve as a warm aromatic spice to sweeten the breath and to appetize food. They are sometimes considered as having a more appreciated taste than the seed of the true cardamom (Elettaria cardamomum (L.) Maton) for which they also serve as a substitute. Steam distillation of the seed yields an essential oil that is used in the perfume and flavour industry. Medicinally the seeds are used as a stomachic, as a remedy against colds and coughs and as a tonic, especially after childbirth. Raw, cooked or steamed young shoots are often eaten as a vegetable. A decoction of the whole plant is drunk as a tonic and to alleviate rheumatic pain. Dried crushed rhizomes are taken to reduce fever and to combat intestinal pains.
Production and international trade
Data on production, consumption, and trade are unreliable because generally no distinction is made between true cardamom and round cardamom. Round cardamom is only grown commercially in Indonesia, primarily in southern Sumatra and Java. The production of cardamom (both species) in Indonesia is still unstable and variable, with 90-300 t produced annually during 1976-1983. In 1984 there were 1000 ha of cultivated cardamom (both species), which produced 935 t of seeds. The bulk was consumed locally (especially in the traditional medicine industry), with 200 t exported. The dried seeds had a value of US$ 1660/t. North America, Europe, and Japan are the main importers of true cardamom, while round cardamom is mostly traded in Asia. However, there is strong competition for this Asian market from other species of false cardamom grown in other South-East Asian countries. Because production is low and variable there are no reliable trade statistics specifically for round cardamom and its production is still included under true cardamom production or in the general category of "spices”.
Properties
Dried round cardamom seed has an essential-oil content of 2-4%, composed primarily of 1,8-cineole (up to 70%), β-pinene (16%), α-pinene (4%), α-terpineol (5%) and humulene (3%). Fresh rhizomes and roots have an essential-oil content of about 0.1% which also contains 1,8-cineole.
Adulterations and substitutes
The primary substitute for round cardamom is true cardamom (Elettaria cardamomum), because of the higher essential-oil content of the dried seeds (5-8%). Other species labeled and used as "false” cardamoms in South-East Asia (see Chapter on "Minor spices” and "Spices with other primary use”) include Amomum acre Valeton, A. krervanh Pierre ex Gagnepain, A. ochreum Ridley, A. testaceum Ridley, A. uliginosum Koenig, A. xanthioides Wallich ex Baker and A. xanthophlebium Baker. Outside South-East Asia, "false” cardamoms include Amomum aromaticum Roxb. and A. subulatum Roxb. (Eastern Himalayas), Alpinia globosa Horan. (Indo-China and China), Aframomum corrorima (Braun) Jansen (Ethiopia), Aframomum daniellii K. Schumann (Cameroon) and Aframomum melegueta (Roscoe) K. Schumann (West Africa).
Description
- Robust, perennial, aromatic herb, up to 2 m tall, with subterranean, copiously branched rhizome from which arise erect leafy stems and separate inflorescences. Rhizome hard, subterete, 1-2 cm in diameter, yellow-white, covered with red-brown, glabrous scales. Leafy stem terete, up to 1.5 m tall and up to 2.5 cm in diameter.
- Leaves alternate, distichous, sessile, sheathed, smelling strongly of turpentine when bruised; ligule semilunar, 5-7 mm tall, deeply emarginate, glabrescent; blade lanceolate, 7.5-50 cm × 3-10 cm, base gradually narrowing, margins finely ciliate, apex acuminate with acumen up to 3 cm long, shiny green with numerous initially white dots that turn blood-red.
- Inflorescence sprouting laterally from the rhizome, sometimes partly subterranean; peduncle ascending, 2-10 cm × 5-6 mm, clothed with dense, imbricate, persistent scales; flower-bearing part of inflorescence spike-like, ellipsoidal or oblongoid, in fruit more ovoid, 3-9 cm × 2-5 cm, densely covered with numerous bracts; sterile bracts absent; fertile bracts ovate-oblong, 1.5-4 cm × 1.5-2.5 cm, acuminate, densely striate, ciliate, silky on the back, persistent, each one covering a bracteole with a sessile flower; bracteole tubular-spathaceous, 3-dentate, silky hairy, much shorter than the calyx; calyx tubular-spathaceous, 1.3 cm long, hairy; corolla tubular, 3-lobed, lobes oblong-linear and about 8 mm long, white or yellowish; labellum broadly elliptical, 15-18 mm × 10-15 mm, narrowed and stalk-like at base, hairy inside, yellow with dark purple median band or yellow-white with purple-margined yellow median band; staminodes absent; stamen 1.3 cm long, filament hairy at base, anther connective distinct and 3-lobed; pistil surrounded by connate stylodes of 2 mm length, style glabrous, stigma cup-shaped and ciliate.
- Fruit a depressed globose capsule, 1-1.5 cm in diameter, densely striate and silky hairy, crowned by the remnants of the flower, yellow-white.
- Seed polygonal, obtuse, about 4 mm long with white aril.
Growth and development
During the first years of growth, flowers produce hardly any fruit. New inflorescences develop continuously from the 3rd or 4th year and produce fruits that mature 1.5-2 months after flowering. Rainfall (or irrigation) promotes flowering, while fruit-set is increased by the presence of pollinating insects.
Other botanical information
There has been no thorough taxonomic revision of the genus Amomum Roxb.; as a result, confusion prevails in the literature. Species from at least 4 different genera (Aframomum K. Schumann, Alpinia Roxb., Amomum Roxb., Elettaria Maton) are indicated with the English vernacular name cardamom. Only Elettaria cardamomum is the "true cardamom”, other species are "false cardamoms”. The round cardamom (Amomum compactum) occurs naturally in western Java only; other cited occurrences refer to other species, to cultivated plants or to escapes from cultivation.
Ecology
Optimum growing conditions for round cardamom are: average annual temperature 23-28 °C (ranging from 10-35 °C), a constant high relative humidity, annual rainfall 2500-4000 mm with at least 136 rainy days and partial shade (arid conditions and direct sunlight are not well tolerated). Well-drained soils with pH 5-6.8 and high organic matter content are preferred. Favorite soil types are latosols, andosols, alluvials and red-yellow podsols with a loamy or sandy loam texture. In the tropics round cardamom grows well at altitudes of 200-1000 m, but greatest yields are obtained at 300-500 m altitude. In Java it grows wild in primary and teak forests.
Propagation and planting
Round cardamom can be propagated by seed but most commonly rhizome cuttings or offsets of the plant clump are used. The rhizome cutting or offset (with rhizome part and adventitious roots) should bear 1-2 shoot buds or young plantlets 10-15 cm tall bearing 4-8 leaves and may bear a 80-100 cm long stem part. Under dry weather conditions some of the lower leaves are removed to prevent rapid dehydration. Planting holes 50 cm deep and wide are first prepared, the soil is loosened and organic matter is incorporated. Per hole 1-2 cuttings are planted about 10 cm deep. Plant spacing is 1.5 m × 1.5 m. Tree crops such as coconut or sugar palm can provide shade. If rainfall is poor, regular watering is necessary until establishment.
Husbandry
Round cardamom should be weeded regularly. Mulching (e.g. using large banana leaves) is recommended. Occasionally the clumps are thinned to 4-5 stems per clump, and the soil around the plants is kept loose to prevent waterlogging. When grown under shade, the shade plants must be pruned and dead or diseased plants removed regularly. One month after planting and every 6 months thereafter, inorganic fertilizer is applied in a circle dug 20 cm deep around the plant. N (45-67 kg), P (34-45 kg), and K (45-100 kg) are applied per ha.
Diseases and pests
No serious diseases and pests of round cardamom have been reported. Pentalonia nigronervosa, a viral disease, causes wilting and dieback. Phyllosticta sp. is a fungal disease attacking the leaves, especially of seedlings. Cephalosporium sp., Pythium aphanidermatum, and P. vexans attack the rhizomes. Control measures are primarily removal of the affected plants, but also avoiding waterlogged soils, and the application of fungicides. Insects, especially maggots, have been reported as attacking all parts of the plant, but no detailed information is available. Rats and bats occasionally cause damage.
Harvesting
The fruits are ready for harvest about 1.5-2 months after flowering. When mature, the fruit feels firm, the corolla has been shed, and the skin is wrinkled and reddish-purple. Harvesting is carried out by cutting the entire fruit cluster and then removing the individual fruits. From the 4th year onwards, round cardamom fruit can be harvested every 35-45 days. In Java, 4 small harvests are possible between January and July (rainy season) and 3 larger ones between August and December (dry season). Fresh plant material such as stems and rhizomes, is harvested as needed for local consumption.
Yield
During the first year yields of round cardamom are quite low. Dry fruit yield can reach 275 kg/ha during the second year, rising to 475 kg/ha during the following years.
Handling after harvest
Round cardamom fruits are washed in a 2% soda solution for 10 minutes, to bleach them. Occasionally they are bleached by steaming with sulphur. They are then dried carefully to prevent fruit splitting, which decreases the quality. A common practice is to sun-dry the fruits for 2-3 hours in the morning and then move them to a shady location for air-drying. This process is repeated for 5-10 days until the fruits are dry and contain 15-20% water. Finally, the fruits are sorted by size and colour.
Genetic resources and breeding
No germplasm collections or breeding programmes are known to exist for round cardamom.
Prospects
It is questionable whether round cardamom will gain in importance economically, since true cardamom produces higher fruit yield and fruits with a higher essential-oil content. It seems that growing true cardamom is more profitable than producing round cardamom. However, the production of true cardamom requires higher inputs of labour than that of round cardamom, and true cardamom does not thrive as readily in Indonesia as round cardamom does.
Literature
- Backer, C.A. & Bakhuizen van den Brink Jr, R.C., 1968. Flora of Java. Vol. 3. Wolters-Noordhoff, Groningen, the Netherlands. pp. 52-53.
- Burkill, I.H., 1966. A dictionary of the economic products of the Malay Peninsula. Revised reprint of the 1935 edition. Ministry of Agriculture and Cooperatives, Kuala Lumpur, Malaysia. pp. 131-137.
- Naiola, B.P., 1978. Mengenal kapulaga (Amomum compactum Soland. ex Maton) dan beberapa kerabatnya [Getting to know round cardamom (Amomum compactum Soland. ex Maton) and some related species]. Buletin Kebun Raya 3(4): 115-119.
- Ochse, J.J. & Bakhuizen van den Brink, R.C., 1980. Vegetables of the Dutch East Indies. 3rd English edition (translation of "Indische groenten”, 1931). Asher & Co., Amsterdam, the Netherlands. pp. 732-734.
- Rismumandar, 1988. Rempah-rempah. Komoditi ekspor Indonesia [Spices. Export commodities of Indonesia]. Sinar Baru, Bandung, Indonesia. pp. 51-69.
- Santoso, H.B., 1988. Kapulaga [Round cardamom]. Penerbit Kanisius, Yogyakarta, Indonesia. 59 pp.
- Valeton, T., 1906. Amomum cardamomum Willd. Icones Bogoriensis 2: Tabula 194. pp. 307-309.
Sources of illustrations
Valeton, T., 1906. Amomum cardamomum Willd. Icones Bogoriensis 2. Fig. 194. Redrawn and adapted by P. Verheij-Hayes.
Authors
- X.Y. Wolff & Hartutiningsih
