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6

MAJOR COLOURANTS AND DYESTUFFS

MAINLY PRODUCED IN HORTICULTURAL SYSTEMS

COCHINEAL AND CARMINE


Summary of Basic Information
 
Usage: (a) Primarily as a colourant for cosmetics and foods.
(b) Very minor usage as a textile dyestuff
Common names for products: (a) The dried insects: cochineal (English); cochinilla or zacatillo (Spanish); cochenille (French); cocciniglia (Italian); cochenille or koschenille or Nopalschildaus (German).
(b) The extract of the insect: carminic acid. (c) The aluminium lake of carminic acid: carmine.
Botanical source: Pregnant females of Dactylopius spp. insects; principally D. coccus Costa (syn. Coccus cacti L. and C. cacti coccinellifera); Dactylopidae family; Coccidae superfamily.
Insect hosts: Cacti of Opuntia spp. ("prickly pear") and Nopalea spp. ("torch thistles"), especially N. cochenillifera.
Distribution: (a) Native to Mexico, Central America and western Andes countries of South America. (b) Widely introduced and naturalised elsewhere in the tropics and sub-tropics.
Products traded internationally: The dried insects and the extracts; the latter predominating today.
World production and trade: Approximately equivalent to 300-350 tonnes of dried insects per annum.
Exporters: (a) Peru (90% plus of world supplies). (b) Canary Islands and some others in Central and South America.
Major importers: USA, Western Europe, Japan.
Availability of reliable published information: Fair to good.

Description and Colourant Uses

Cochineal is the name used to describe both the colour and the raw material source: the dried, pregnant females of tropical American Dactylopius species, especially D. coccus Costa. The main hosts of these scale insects are the aerial parts of "prickly pear" and "torch thistle" cacti (Opuntia and Nopalea species, respectively). Less important host plants in the tropical Americas include Schinus molle, Acacia macarantha and Caesalpinia spinosa.

The principal pigment in cochineal is a protein-bound glycoside of the anthraquinone, carminic acid. This is very soluble in water and its colour changes according to pH. An orange colour is obtained in an acidic media and a transformation from violet to red occurs with increasing pH number from 5 to 7. Carminic acid extracts display good stability to heat, light and oxygen.

Treatment of carminic acid with an aluminium salt produces a soluble aluminium lake, known as carmine, which may be precipitated by addition of a calcium salt. Carmine exhibits good resistance to heat, light and oxygen and provides a blue to red colour in alkaline solution. Reduction of the pH reduces the blue colour and below pH 3 carmine is insoluble. Precipitation of carmine with tin salts produces a vivid scarlet colour which was formerly important in textile dyeing.

The major usage of carminic acid and carmine today lies in non-textile applications. Carmine is an important colourant for cosmetics, especially those employed near the eye. Carminic acid and particularly carmine aluminium lake are permitted and widely used in the food industries in North America and Western Europe. Extensive toxicological screening in the European Community has resulted in the listing of cochineal and its derivatives as E120, "Natural Red" but individual European countries have their own regulations on the permitted range of food/beverage applications and on dosage levels. In Japan, carminic acid rather than carmine is employed by the food industry.

Carminic acid is usually supplied as an aqueous solution with a pigment content of less than 5% and at this low colouring power its range of applications are limited. Spray dried forms are available also.

Carmine is the main product employed for cosmetics, food and pharmaceutical colouring applications. It is most commonly traded as a powder with a carminic acid content of 40 to 60%. Liquid aqueous alkaline forms (and their spray dried derivatives) are also available with a carminic acid content of 2 to 7%; potassium hydroxide solutions have largely displaced the traditional ammonia medium. Carmine competes with beetroot red (betanin) and anthocyanins in food colouring and its main limitation is insolubility at low pH. Typical applications are in soft and alcoholic drinks, bakery products, dairy products, confectionery and pickles and at dosage levels ranging from 0.1 to 0.5%.

Current dyestuff usage is minor and limited to those who require special tones for luxury textiles or artists' paints.

World Demand and Supply Trends

The use of cochineal as a textile and paint dyestuff in Mexico and Peru dates back almost 3,000 years. The commercial potential was quickly recognized by the Spaniards on their conquest of the Aztec Empire of Mexico. Cochineal was introduced to Europe in the early years of the sixteenth century, achieving the status of a well-known item of trade within fifty years. Its superiority over kermes in textile dyeing was rapidly acknowledged and demand for the latter progressively eroded along with increased supplies of the New World material. Cultivation of cochineal was actively promoted by Spain in its colonies in the Americas and the industry played a formative economic development role in some countries, notably in Guatemala.

By the early nineteenth century, the cochineal insect and its cactus host had been widely introduced by Spain and its colonial rivals to many parts of the Old World. A peak global production and trade of many thousands of tonnes per annum was attained in the mid-nineteenth century, with Mexico, Guatemala, Haiti, Java and the Canary Islands being prominent sources; exports from the last named were as high as 3,000 tonnes in 1875.

The development of synthetic, coal-tar based dyes in the latter part of the nineteenth century resulted in a progressive reduction of demand for cochineal in the textile industry. However, it held a share of the market for a much longer period than most natural dyestuffs and, for example, was used as the scarlet dye for the dress uniforms of the British Brigade of Guards until the mid-1950s.

Current major usage of cochineal and its derivatives lies exclusively in the cosmetics and food industries with Western Europe (notably France and the UK), the USA, Japan and Argentina as the principal markets (listed in descending order). Total demand in 1995 was estimated to be in excess of 300 tonnes of cochineal per annum. Peru has been the dominant exporter for several decades, accounting for 90% or greater of the export market. The only other significant supplier has been the Canary Islands with exports fluctuating between 10 and 30 tonnes per annum.

Prior to 1980, all Peruvian exports were in the form of raw cochineal. In the subsequent period, an extraction industry has developed in Peru and today over 50% of the annual crop is processed to carmine prior to export. A small quantity of carminic acid is produced also. The major buyer of carmine is Western Europe, followed by the USA. Japan predominantly imports cochineal for local processing. The volume and value of Peruvian exports in the recent period are given in the following table:

Table 11: Peruvian production and exports, 1986-1993


 
Cochineal
Carmine
Year
Production (tonnes)
Exports (tonnes)
Value
(US$ millions)
Exports (tonnes)
Value
(US$ millions)
1986
266
139
6.1
19.2
4.6
1987
320
118
6.4
31.7
7.9
1988
319
141
5.9
30.4
7.0
1989
355
177
5.3
47.8
6.9
1990
383
189
5.7
46.7
7.1
1991
399
160
2.7
59.8
6.9
1992
493
193
3.1
74.9
7.7
1993
500
NA
NA
NA
NA

NA = not available
Source: Peruvian Government exports statistics.

These figures show a considerable improvement on raw material production as compared to the latter half of the 1970s and early 1980s when the average annual output fluctuated around 180 tonnes. Supply problems and associated high prices (reaching around US$ 100/kg, fob for cochineal) were particularly acute in some years in the early 1980s owing to a combination of factors. Peru is largely dependent upon harvesting wild material and the major source is the Ayacucho area (with approximately 35,000 ha of wild cacti) which was subject to terrorist disturbance in the early 1980s. Simultaneously, the new extraction industry posed competition to the traditional exporters for the limited supplies and this was exploited by middlemen in the marketing chain. Subsequently, the Peruvian Government imposed a quota system on division of the crop between the two export channels and this, together with other general improvements, has led to greater stability. Cultivation has been adopted also since the mid-1980s and the size of individual plantations range from 1 to 20 ha.

Increased availability of raw material has led to a progressive reduction in fob export prices from around US$ 50/kg and US$ 250/kg for cochineal and carmine, respectively, to US$ 17/kg and US$ 100/kg in the recent period. The recent price levels are of a similar order of magnitude to those prevailing in the mid-1970s.

Exports of cochineal from the Canary Islands have been mainly destined for Western Europe and historically have been higher-priced than Peruvian material.

The consumption of cochineal and carmine in the major markets has increased substantially along with supplies, price stability and the trend towards natural colours in foodstuffs. Prospects for significant further expansion in these traditional markets is uncertain but globally a modest growth is likely.

Several countries - where the insect and its host cactus are indigenous or have naturalised - have expressed interest in resuscitating or newly developing cochineal production. Their prospects for success will depend on local production costs as compared to Peru and, also, on the output levels achieved by the latter if formal cultivation is widely adopted.

Cultivation and Primary Processing

The insects and their host cacti are adapted to arid areas of the tropics and sub-tropics and in many areas of introduction the cacti have achieved the status of a weed.

When cultivated, a host plant is inoculated with a brood of the insects which are readily collected since they mass together. The females mature over a period of 90-110 days and, thus, under favourable weather conditions up to four harvests can be taken a year.

Harvesting involves brushing the white-grey, powdery mass of females off the plant immediately prior to egg laying. Primary processing involves killing and drying the females, during which their weight reduces by 70%. Simple sun-drying of the insects provides "silver cochineal" which includes the brood powder and is regarded as of inferior quality. Accelerated, artificial killing and drying gives the more highly regarded "black cochineal"; several variants have been employed and in Peru a brief immersion in hot water, followed by sun-drying is the commonest method.

Cleaning and grading is normally undertaken by exporters. This involves removal of extraneous matter by manual sifting and sieving and redrying, if necessary, to 12% moisture content.

Between 80 and 100 thousand insects are required to produce 1 kg of cochineal. Yields from cultivation in Peru have been reported to range from 120-240 kg/ha/year.

Some reports in the literature state that in Mexico and Central America a distinction was made between cultivated and wild strains of insects, the former were larger and contain double the pigment content (up to 22%). While precise species/strain identification can be difficult over a wide geographic range, wild insects in Peru regularly contain at least 16% carminic acid and have frequently attained 20%. It is possible that the low pigment content of some wild material results from premature harvesting, especially in years of high prices.

Added-Value Processing

Carminic acid has a good solubility in water and cochineal has been traditionally extracted with water or aqueous alcohol at 90-100?C by a batch or continuous process. For sale of carminic acid, the extracts are concentrated to provide solutions of between 2 and 5% (maximum) pigment content. Use of protolytic enzymes has been reported to improve extraction yields considerably.

Carmine for the food and cosmetics industries is prepared from the carminic acid extract by treatment with an aluminium salt and aluminium hydroxide substrate. Addition of ethanol to the complex provides soluble carmine while treatment with a calcium salt results in precipitation. Between 4-5 kg of cochineal are required to produce 1 kg of the carmine lake. In the solid form, the carminic acid content of carmine is usually a minimum of 50% but rarely exceeds 60%. Treatment of carmine with aqueous ammonia provides the traditional soluble red form of the colourant.

Production of dyers scarlet involves a similar process but aluminium is substituted by tin salts.

Other Uses

Cochineal found use in European medicine up to the mid-nineteenth century and, possibly, was employed in Aztec and Inca traditional medicine.

The main new interest in the insect lies in its use as a biological control agent in areas where Opuntia cacti pose problems as weeds. In some countries, development of cochineal production has been proposed as a spin-off from the cacti control operation.

SELECTED BIBLIOGRAPHY

Production, Trade and Multi-Topic Reviews

ANAND, N. (1983). The Market for Annatto and Other Natural Colouring Materials, with Special Reference to the United Kingdom. UK: Tropical Development and Research Institute Report No. G174.

BARRIGA RUIZ, C.A. (1994). Cochineal production in Peru. Paper presented at the FAO Expert Consultation Meeting on Non-wood Forest Products in Latin America, held in Santiago, Chile in July 1994.

BARYANYOVITS, F.L.C. (1978). Cochineal carmine: an ancient dye with a modern role. Endeavour (New Series), 2(2), 85-92.

CLOUDSLEY-THOMPSON, J.L. (1986). Cochineal. Antenna, 10(2), 70-72.

DONKIN, R.A. (1977). Anthropus, 72, 847.

DONKIN, R.A. (1977). "Spanish Red". An ethnogeographical study of cochineal and the Optuntia cactus. Trans. Amer. Philosoph. Soc., 67(5).

RODRIGUEZ-HERNANDEZ, I. et al. (1988). The cochineal - a singular parasite. Agricultura Madrid, 57(677), 914-919.

SCHWEPPE, H. and ROOSEN-RUNGE, H. (1979). Carmine - cochineal carmine and kermes carmine. Carmine, 255-283.

WRIGHT, N.P. (1963). A thousand years of cochineal. American Dyestuff Reporter, 52, 635-639.

Food Usage and Related Legislation

HENRY, B.S. (1992). Pp. 63-67. In: Natural Food Colourants, edited by G.A.F. Hendry and J.D. Houghton. Glasgow, UK: Blackie and Son Ltd.

MARMION, D.M. (1984). Handbook of US Colourants for Foods, Drugs and Cosmetics. New York: John Wiley and Sons.

Textile Dyeing

ANON. (1983). Natural dyes debuted. Chemical Marketing Reporter, 244(19), 9.

KASHINO, E. et al. (1986). Studies on the dyeing properties of fibres by natural dyes (V). Dye affinity of cochineal for various fibres. Kiyo Kyoritsu Joshi Tanki Daigaku (Kaseika), 29, 85-93. (In Japanese).

KASHINO, E. et al. (1990). Studies of the dyeing properties of fibres by natural dyes (IX). The effects of tannic acid on the dyeing properties of cochineal. Kiyo Kyoritsu Joshi Tanki Daigaku (Kaseika), 33, 95-105.

MCLAREN, K. (1983). The Colour Science of Dyes and Pigments. Bristol, UK: Adam Hilger Ltd.

VERHECKEN, A. (1990). Kermes and cochineal dyeing. Reply to comments. J. Soc. Dyers Colour, 106(3), 114.

ZIDERMAN, I. (1990). Kermes and cochineal dyeing. J. Soc. Dyers Colour, 106(3), 113?114.

Chemistry and Analytical Methods

FRANCIS, F.J. (1992). Pp. 253-256. In: Natural Food Colourants, edited by G.A.F. Hendley and J.D. Houghton. Glasgow, UK: Blackie and Son Ltd.

LLOYD, A.G. (1980). Extraction and chemistry of cochineal. Food Chem., 5, 91-107.

NISHIZAWA, M. et al. (1985). Analysis of natural dyes (III). Analysis of cochineal dye and lac dye in foods and dyes. Hokkaidoritsu Eisei Kenyushoho, 35, 7-11.

SCHWING-WEILL, M.J. and WECHSLER, S. (1986). Spectrophotometric study of carminic acid in solution. Application to its determination. Analusis, 14(6), 290-295.

WOUTERS, J. (1985). High performance liquid chromatography of anthraquinones: analysis of plant and insect extracts and dyed textiles. Stud. Conserv., 30(3), 119-128.

WOUTERS, J. and VERHECKEN, A. (1989). The scale insect dyes. Species recognition by HPLC and diode-array analysis of the dyestuffs. Annales Soc. Entom. France, 25(4), 393?410.

YAMADA, S. et al. (1993). Analysis of natural colouring matters in food (IV). Methylation of cochineal colour with diazomethane for analysis of food products. J. Agric. Food Chem., 41(7), 1071-1075.

Use of the Insect for Cactus Control; Entomology

BRUTSCH, M.O. and ZIMMERMAN, H.G. (1993). The prickly pear (Opuntia ficus-indica) in South Africa: utilization of the naturalized weed and the cultivated plants. Econ. Bot., 47(2), 154-162.

CRAWLEY, M.J. (1990). Plant life-history and the success of weed biological control projects, pp. 17-26. In: Proceedings of the VIII Int. Symposium on Biological Control of Weed, Rome 1990. Rome: Instituto Sperimentale per la Patologia Vegetale, Min. Agric.

GUERRA, G.P. and KOSZTARAB, M. (1992). Biosystematics of the family Dactylopiidae with emphasis on the life cycle of Dactylopius coccus Costa. Bull. Virginia Agric. Expt. Station, 92(1), 90.

MORAN, V.C. and COBBY, B.S. (1979). On the life-history and fecundity of the cochineal insect, Dactylopius austrinus De Lotto, a biological control agent for the cactus Opuntia aurantiaca in Australia and South Africa. Bull. Entomological Res., 69(4), 629-636.

ZIMMERMAN, H.G. (1979). Herbicidal control in relation to Opuntia aurantiaca Lindley and effects on cochineal populations (Dactylopius austrinus). Weed Research, 19(2), 89-93.

ZIMMERMAN, H.G. (1990). The utilization of an invader cactus weed as part of an integrated control approach, pp. 429-432. In: Proceedings of VIII Int. Symposium on Biological Control of Weeds, Rome 1990. Rome: Instituto Sperimentale per la Patologia Vegetale, Min. Agric.

CROCIN FROM SAFFRON AND GARDENIA JASMINOIDES

Summary of Basic Information


 
Saffron
Gardenia jasminoides
Usage: For flavouring and imparting a yellow colour to foods. Yellow food colourant.
Common name for processed product: Saffron extract or crocin extract. Crocin extract; gardenia extract.
Raw material source: Stigmas of a crocus; mainly cultivated. Fruits of a shrub; mainly cultivated.
Botanical source: Crocus sativus L. (Family: Iridaceae). Gardenia jasminoides Ellis (Family: Rubiaceae).
Synonyms for botanical source:   Gardenia florida L; Gardenia grandiflora Lour; Gardenia augusta (L) Merr.
Common names for botanical source: Saffron (English); safran (French and German); azafran (Spanish); fan-hung-hua (Chinese); saufuran (Japanese); Za'faran (Arabic). Cape Jasmine, garden gardenia; bunga cina (Malaysia); ceplok piring (Indonesia); rosal (the Philippines); phut cheen (Thailand).
Distribution: Indigenous to Greece, Turkey and Iran; now widely cultivated across temperature zones from Europe to China and in the Americas. Indigenous to southern China and Japan; widely cultivated elsewhere, especially in Southeast Asia.
Form traded internationally: As dried stigmas.  
World production of raw material: Unknown. Unknown but much greater than international trade.
International Trade: Possibly 50 tonnes/annum of saffron. Unquantified but small.
Major exporters: Spain, Iran in the first rank. India in second rank. China.
Major importers: Gulf and Middle East states. Far East and Southeast Asian countries.
Availability of reliable published information: Good. Poor.

Description and Colourant Uses

Crocin extract is the trade term for the yellow, water-soluble food colourant obtained from cape jasmine (Gardenia jasminoides L.) and from saffron (Crocus sativus L.). However, the extracts are not used interchangeably in all applications since saffron is valued as much for its aroma and flavour as for its colouring properties and, moreover, it is the world's most expensive spice/colourant.



Saffron is the dried stigma of a crocus which originated in Greece and Asia Minor but which is now widely cultivated in a band from Western Europe through temperate and sub-tropical Asia to China. Saffron has been used as a spice from ancient times in the Mediterranean and from the Middle Ages it achieved great popularity throughout Europe with commercial cultivation being undertaken in several northern Europe countries until the eighteenth century. The spice is an essential ingredient for the preparation of many southern European regional dishes, such as paella (rice, meat, fish and vegetables) and arroz con pollo (rice and chicken) in Spain and bouillabaisse (fish and shellfish stew) in France. Other traditional applications for saffron in Europe include bakery products and sugar confectionery. Saffron extract is widely used in the food industry today for top-of-the-range products at typical dosage levels of 0.1 to 0.2% (weight for weight) to impart a characteristic flavour, along with a water soluble and heat stable yellow colour. In the European Community, saffron extract does not have an "E number" and falls into the category of "natural extracts".






Cape jasmine (Gardenia jasminoides Ellis) is an evergreen shrub which originates from southern China and Japan. It is now widely cultivated in the tropics and sub-tropics, particularly in Southeast Asia both as a garden ornamental and as a source of a yellow food colourant. The pigments are contained in the fruit, which is used in the Far East either directly or after drying in a wide range of dishes and as a tea infusion. In recent years, usage of the extract has developed in the processed food industries in Western Europe as a less expensive colourant substitute for saffron in applications where the latter's flavour is not required. It is usually sold under the name of "crocin extract". Typical dosage levels of the extract in confectionery and bakery products range from 0.05 to 0.1%, while fish products in brine may contain up to 1.5%. In the European Community, the extract of cape jasmine fruit is described as a "natural colour" and it does not have an "E number".

The major yellow pigment present in both saffron stigmas and cape jasmine fruits is crocin, the gentiobiose form of the carotenoid crocetin. In addition to the crocins, cape jasmine fruits contain iridoid and flavanoid pigments. The aroma of saffron arises from a volatile aldehyde, safranal, which is produced during processing from picrocrocin; the latter is responsible for the bitter taste of saffron.

World Demand and Supply Trends

The international market for saffron was dominated by Spain up until the recent period owing to the volume and quality of its production. Today, Spain retains its position as the supplier of the best quality material but the high costs for the labour-intensive harvesting have reduced annual output from around 60 tonnes in 1970 to below 20 tonnes in the early 1990s. The main beneficiary has been Iran while smaller volumes are exported regularly by India (around 10 tonnes), some Mediterranean and South American countries.

Quantification of the international trade in saffron is made difficult by the shortcomings in the statistics of many countries. Total annual trade is perhaps 50 tonnes, with Western Europe, North America and the Gulf States as the major markets. Japan and South American countries are also significant, if smaller, consumers. The principal supplier to all markets, excepting the Gulf States, is Spain but it also imports Iranian and Indian material which, presumably, re-enters trade under a Spanish label. Annual import levels for individual countries fluctuate in response to availability and prices; the USA, for example, took 3 tonnes in 1992 and this level rose to 8.3 tonnes in 1994.

Prices for saffron undergo significant swings and over the period 1980 to 1994 the New York spot market price for Spanish material moved between US$ 574 to 1,304 per kg; peaks were in 1980 and 1988-90 and troughs occurred in 1985 and 1994. Iranian and Indian material is highly discounted in price, reflecting the poorer quality when compared to that of Spanish saffron.

No detailed information is available on the breakdown of usage of saffron between direct incorporation in foods and in the form of its extract in the individual developed country markets. However, extract usage can be expected to be higher in countries such as the United Kingdom and the USA than in France and Spain.

It is likely that saffron cultivation will decline further in Spain along with the adoption of more remunerative crops and the drift of labour away from rural areas. This might provide an opportunity for the entrance to the market of new, low cost producers, provided that attention is paid to product quality.

No reliable production data are available on cape jasmin fruits but the volume is believed to be substantial in Southeast Asia and the Far East. Interest in the extract as a colourant by the Western European food industry has grown in recent years since it is one-tenth of the cost of saffron and does not have a strong flavour. However, current consumption is small. The extract is mainly sourced from China.

The level of usage of saffron and its extract in traditional saffron dishes in Western Europe and North America is expected to remain stable and perhaps to grow modestly along with the processed food industry. The future growth prospects for cape jasmin fruit extract in these markets will depend to a large extent upon trends in food legislation. As a non-traditional food additive, it is possible that cape jasmine extract may need to undergo costly toxicological testing before receiving approval as a natural colour for use in foods.

Cultivation and Processing

Saffron

Crocus sativus L. is a perennial which resembles the purple spring crocus but blooms in the autumn. It is adaptable to a wide range of climates from the temperate to the sub-tropical and on soils varying from sandy to well-drained clay loams. Most commercial production areas may be described as dry and in Spain the rainfall rarely exceeds 400 mm per year. Two heavy rainfalls are sufficient, one in the spring and the other in the autumn.

Propagation is by means of corms; these are produced annually by the mother corm which withers away and feeds the young cormlets. A plot of saffron is usually cultivated for four years before replanting with selected, disease-free corms. Planting is undertaken in the late spring on well-cultivated land which has been treated with compost and, where necessary, adequately limed. Typical spacing distances are 10-25 cm in double rows in trenches.

Cultivation in the first year is restricted to weeding and turning the top soil between rows in September before the plants sprout. After the harvest in October, the soil between rows is dug again and manuring may be repeated. The leaves are removed in the following April or May and these are often dried for use as winter fodder for animals.

Harvesting spans four to six weeks in the autumn. Each plant only flowers for about fifteen days and harvesting, therefore, must be timely. Intact flowers are picked and this is done early in the morning to prevent withering. On the same day the stigmas must be removed from the harvested flowers and drying be initiated.

Fresh stigmas are odourless and the characteristic aroma develops only after stimulation of enzymatic action during the drying operation. Slow, sun-drying invariably results in a product of poor flavour quality and appearance. Careful artificial drying provides a superior product and in Spain various techniques are employed, including revolving drum driers.

Yields of flowers vary considerably according to local site conditions. On average, however, about one hectare yields one million blooms, weighing approximately 800 kg, which provide 50 kg of fresh stigmas and 10 kg of dried saffron.

Grading involves classifying dried stigmas by length, colour, aroma and freedom from extraneous matter. Spanish saffron grades range from "very select" with stigma lengths of over 30 mm and a style of 23-24 mm to "ordinary" with a stigma length of 20-24 mm.

Saffron extract is usually prepared by treatment with aqueous alcohol, followed by careful concentration. Approximately 140,000 stigmas are required to produce 1 kg of extract.

Cape Jasmine

Gardenia jasminoides Ellis originates from temperate areas but grows well in the tropics at altitudes above 400 m. It requires an open sunny position on well-drained soils and prefers a soil pH of 6 to 7.

Propagation is usually undertaken with cuttings or by marcotting. Flowering may commence one year after field establishment.

For manufacture of the extract, fruits are first dried and are then extracted with aqueous alcohol. Crocin yields of up to 10% have been reported for dried fruit.

Patents have been published on extraction methodology and subsequent treatment with proteases or beta-glycosides to produce a range of colours.

Other Uses

Saffron was employed as a textile dye prior to the advent of coal tar based synthetics. Additionally, it plays a role in traditional Indian medicine and, formerly, was used in Europe for treatment of various disorders.

Cape jasmine fruit are employed on a small-scale for craft-dyeing in the Far East and several parts of the plant are employed in traditional medicine. The plant is widely grown as an ornamental.

SELECTED BIBLIOGRAPHY

Saffron

ALONSO, G.L. et al. (1990). Auto-oxidation in saffron. J. Food Sci., 55(2), 595-596.

BASKER, D. and NEGBI, M. (1983). Uses of saffron. Economic Botany, 37(2), 228-236.

CORRADI, C. and MICHELI, G. (1979). General characteristics of saffron. Boll. Chim. Farm (Milan), 118(9), 537-552.

FRANCIS, F.J. (1992). Pp. 248-249. In: Natural Food Colourants, edited by G.A.F. Hendry and J.D. Houghton. Glasgow: Blackie and Son Ltd.

GARRIDO, J.L. et al. (1987). Flavanoid composition of hydrolysed petal extracts from Crocus sativus L. Anales de Bromatologia, 39(1), 69-80.

INGRAM, J.G. (1969). Saffron (Crocus sativus L.). Tropical Science, 11(3), 177-184.

INTERNATIONAL STANDARDIZATION ORGANISATION (1993). ISO 3632-1: Saffron (Crocus sativus L.), Part 1 - Specification. Geneva: ISO.

ITC (1982). Spices - A Survey of the World Market. 2 volumes. Geneva, Switzerland: International Trade Centre.

ITC (1992). Imports of Spices into Selected Markets, 1987-1991, pp. 275-376. In: Report of the Third Meeting of the International Spice Group, Kingston, Jamaica, November 1991. Geneva, Switzerland: International Trade Centre.

ROSENGARTEN, F. (1969). The Book of Spices. Wynnewood, Penn., USA: Livingston Publishing Co.

SOLINAS, M. and CICHELLI, A. (1988). HPLC analysis of the colour and aroma constituents of saffron. Industrie Alimentari, 27(262), 634-639.

SAMPATHU, S.R. et al. (1984). Saffron cultivation, processing, chemistry and standardization. CRC Critical Reviews in Food Science and Nutrition, 20(2), 123-157.

USDA (1995). US spice trade, pp. 38-82. In: Tropical Products: World Markets and Trade. Washington DC: United States Department of Agriculture Foreign Agricultural Service Circular Series FTROP 1-95, April 1995.

Cape Jasmine

GEORGE, P.S. et al. (1993). Clonal multiplication of Gardenia jasminoides Ellis through auxiliary bud culture. Plant Cell Reports, 13(1), 59-62.

FRANCIS, F.J. (1987. Lesser-known colourants. Food Technol. (Chicago: Inst. of Food Technologist), 42(4), 62-68.

FRANCIS, F.J. (1991). In: Natural Food Colourants, edited by G.A.F. Hendry and J. D. Houghton. Glasgow: Blackie.

KAMIKURA, M. and NAKAZATO, K. (1984). Comparison of natural yellow colours from saffron and gardenia fruit. Bull. Nat. Inst. Hygenic Sci. (Eisei Shikenjo Hokuku), 103, 157?160.

KAMIKURA, M. and NAKAZATO, K. (1984). Natural yellow colours from gardenia fruit and colours found in commercial gardenia extract. Analysis of natural yellow colours by high performance liquid chromatography. J. Food Hygiene Soc. Japan, 26(2), 150-159.

KIM, D.Y. and KIM, K. (1975). Gardenia jasminoides Ellis pigments. J. Korean Agric. Chem. Soc., 18(2), 98-101.

KOGA, K. et al. (1989). Natural blue dye composition prepared by reacting taurine and genipin. United States Patent.

NAWA, Y. and OHTANI, T. 1992). Induction of callus from flesh of Gardenia jasminoides Ellis fruit and formation of the yellow pigment in the callus. Biosci., Biotechnol. and Biochem, 56(11), 1732-1736.

NODA, N. et al. (1983). Determination of natural yellow dye from the fruits of gardenia by detecting geniposide. J. Hygenic Chem. (Eisei Kagaku), 29(1), 7-12.

SASTRI, B.N.; editor (1956). The Wealth of India. Raw Materials, Vol. 4, p. 110. New Delhi, India: Council of Scientific and Industrial Research.

SHEO, H.J. (1981). A study of the development of food dye from Gardenia fructus. Korean J. Nutrition, 14(1), 26-33.

YU, J.H. et al. (1975). Extraction of orange-yellow pigment from defatted gardenia. Korean J. Food Sci. and Technol., 7(1), 30-36.

INDIGO

Summary of Basic Information
Usage: Blue dyestuff for textiles.
Common name for product: (Natural) indigo dye; Indian indigo.
Raw material source: Leaf and stems of cultivated perennial shrubs.
Botanical source: Indigofera spp. (family: Leguminosae), especially I. arrecta Hochst. and I. tinctoria L.
Common name for botanical source: I. arrecta - Natal indigo; I. tinctoria - Indian indigo.
Distribution: Widespread through Asia, Africa and the Americas.
Form traded internationally: Solid or powdered extract.
World production: Data unavailable.
World trade: Small, possibly 50 tonnes/year.
Exporters: India and possibly some others.
Importers: Western Europe, North America, Japan.
Availability of reliable published information: Fair.

Description and Dyestuff Uses

Indigo is one of the most ancient blue dyes used by man for textiles. The pigment is present in the leaves of a number of Indigofera species, of which the Asian I. tinctoria and the African I. arrecta have been the most important for commercial production.

The major pigment, indigo, obtained from Indigofera species is identical to that of woad (Isatis tinctoria), the body-paint of the Ancient Britons. The indigo dyestuff is not present in the living plants but is formed post-harvest by hydrolysis of indican glucoside to indoxyl which is then subjected to oxidation. It is one of the few natural dyestuffs whose fastness properties are not improved by mordanting.

World Demand and Supply Trends

Indian indigo (from I. tinctoria) became available in Europe in the twelfth century but encountered major opposition from the woad growers of England, France and Germany until the sixteenth century. Thereafter, indigo achieved dominance over woad owing to the combination of its higher dyestuff content, lower cost, the opening of the sea route to India and, somewhat later, by the development of plantations in the Americas.

Prior to the manufacture of synthetic indigo at the end of the nineteenth century, natural indigo was probably the most widely used natural dyestuff in the textile industry and had particular importance for wool. However, the market share of the natural product fell to 4% by 1914. For India, the cultivated area and annual dye production in the 1890s were around 0.6 million ha and 3,000 tonnes, respectively, while the figures in the 1950s were 4,000 ha and 50 tonnes.

Today, indigo is still cultivated in India, parts of Southeast Asia and Africa. It is employed locally in craft dyeing (batik production, etc.) and there is a small export trade. Some recent resurgence of interest in natural indigo has been shown in the West European and North American markets for use with denim fabrics where the "faded look" is fashionable. As yet, however, this has not resulted in any clear upturn in international trade; for example, India's exports over 1988-93 show an erratic fluctuation between 2 and 20 tonnes rather than a steady growth.

There have been reports, also, of the development in the USA of a bio-technological method for the production of "natural indigo" from bacteria but its impact on the market is not yet clear.

Cultivation and Processing

Soil and Climate

Most of the commercial Indigofera species are adaptable to a range of climates in the tropics and warmer areas of the sub-tropics but display differing performance. Growth is best on permeable soils which are rich in organic matter.

Propagation and Husbandry

Multiplication is usually by means of seed and pre-soaking in water can assist germination. Field spacing of plants is dependent upon the species and its growth characteristics, but 50-60 cm spacing is common.

Husbandry involves little more than irrigation of young plants, when necessary, and weed control between planting and harvest(s).

While Indigofera species are perennial shrubs, the economic lifetime varies between 1 and 3 years according to the species and local conditions. The first harvest is taken at three or four months from sowing and this involves cutting the stems 10-20 cm above ground level. Under favourable conditions, three crops may be obtained per year.

There is a paucity of reliable information in the literature on crop yields for the various species. However, I. arrecta is regarded as much superior to I. tinctoria and the former has largely supplanted the latter in India. I. arrecta is reported to provide between 130 to 325 kg/ha year of indigo extract.

Processing

Freshly cut leaf, usually with stem attached, is subjected to extraction as soon as possible after harvesting. The operation involves soaking the fresh material in water for 10-15 hours during which fermentation of the indican glucoside occurs. The liquid is then run off and is aerated to achieve oxidation. After a settling period, the sludge of indigo is separated and is then dried into a cake.

Dyeing is carried out in vats containing alkali as a solubilising agent and with a reducing agent present. The textile is dipped into the vat and is then dried in the air; the blue colour of the textile develops during the final stage.

Other Uses

Parts of Indigofera species have been used throughout the tropics in traditional medicine and some attention has been given in recent years to their potential in modern medicine.

In some areas, the plants are used as a cover crop and a green manure.

SELECTED BIBLIOGRAPHY


ANON. (1991). Indigo. Biotechnol. News, 17(25), 5.

BYRNE, M. (1981). Indigo dyeing: past and present. J. Consumer Studies and Home Economics, 5, 219-227.

CLARK, R.J.H. et al. (1993). Indigo, woad and Tyrian purple. Important vat dyes from antiquity to the present. Endeavour, 17(4), 191-199.

DEKORT, I. and THIJSSE, G. (1984). A revision of Indigofera in Southeast Asia. Blumea, 30, 89-151.

HAN, J. (1988). Traditional Chinese medicine and the search for new antineoplastic drugs. J. Ethnopharmacology, 24(1), 1-17.

LEMMENS, R.H.M.J. and WULJARNI - SOETJIPO, N. (1991). Plant Resources of South-East Asia. Wageningen, Holland: Pudoc/Prosea.

MCLAREN, K. (1983). The Colour Science of Dyes and Pigments. Bristol, UK: Adam Hilger Ltd.

PHILIP, J. et al. (1991). Standardization of vegetative propagation techniques in some of the medicinal plants grown in Kerala. Indian Cocoa Arecanut Spices J., 15(1), 12-14.

RASULOVA, M.R. et al. (1986). Prospects of Lawsonia inermis., Indigofera tinctoria and I. articulata introduction in Taijik SSR. Rastitel nye Resursy, 22(2), 227-233.

REED, P. (1992). The British chemical industry and the indigo trade. British J. History of Science, 25(84), 113-125.

ROBERTSON, S. (1973). Dyes from Plants. New York: Van Nostrand Rheinhold Co.

SASTRI, B.N., editor. (1959). The Wealth of India. Raw Materials. Vol. 5, pp. 173-184. New Delhi, India: Council for Scientific and Industrial Research.

STROEBEL, J. and GROGER, D. (1989). Indigo precursors in Isatis species. Biochemie Physiologie Planzen, 184(3/4), 321-327.

TEWARI, D.N. (1994). Tropical Forest Produce. Dehra Dun, India: Int. Book Distributors.

MADDER


Summary of Basic Information
Usage: Red dye for textiles.
Common name for product: Madder.
Raw material source: Roots of a cultivated perennial, climbing herb.
Botanical source: Rubia tinctoria L. (family: Rubiaceae).
Common name for botanical source: European madder.
Distribution: Indigenous to Europe and Asia Minor. Introduced to India and elsewhere.
World production and trade: Undocumented; certainly small.
Availability of reliable published information: Fair.

Description and Dyestuff Uses

The madders are perennial, climbing herbs with a wide geographic distribution and the roots of certain species have been exploited as the source of a red dyestuff for textiles since ancient times. Amongst the Asian species, Indian madder (R. cordifolia L.) has a long history but European madder (R. tinctoria L.) was the most important for commercial production and this was introduced to India as a superior dyestuff source.

The major pigments obtained from European madder are the anthraquinones alizarin and purpurin, but isolation requires the prior hydrolysis of the glucoside precursor in the roots. Indian madder mainly yields purpurin.

Alizarin gives an intense red colour on conversion to an insoluble lake by the addition of alum and alkali. Depending on the mordant used, the colour shade can be modified through red, pink, orange, lilac and brown. The importance of madder as a red dyestuff for textiles, especially with cotton and linen, expanded upon the adoption of the "Turkey red" process in which calcium is incorporated in the pigment complex. However, alizarin was amongst the first dyes to be synthesised in the second half of the nineteenth century and the natural material was rapidly displaced from the market.
 
 

World Demand and Supply Trends

Small-scale production of European madder is still carried out in Kashmir in India and, possibly, elsewhere. In India, the natural dyestuff is employed for craft dyeing and there is a very minor demand for craft dyeing and artists' paints in Western Europe and North America.

No significant resurgence in usage is foreseen since synthetic alizarin in most applications is superior and cheaper than madder.
 
 

Cultivation and Processing

R. tinctorium is adaptable to temperate and sub-tropical climates and prefers moist, limey soils. Propagation is usually by means of buds or sets from the rootstock at about 1,400 kg/ha. Alternatively, it may be grown from seed, using about 60 kg/ha.

Husbandry involves weeding and providing support for the climbing aerial parts. Harvesting of the roots is undertaken at an age of two or three years and this is normally done around the flowering period when the pigment content reaches a maximum.

After harvesting the roots are washed and dried. The pigment glucoside content ranges from 2 to 3.5% in the dried roots. Soaking the roots in water promotes release of the dye by hydrolytic fermentation.
 
 

Other Uses

Rubia species play a role in traditional medicine in Asia and may be used as a cattle fodder. In the latter application, however, the pigmented species can cause discolouration of the animal's milk.
 

SELECTED BIBLIOGRAPHY


ANON. (1993). Natural dyes debuted. Chemical Marketing Reporter, 244(19), 9.

CHADHA, Y.R. (editor). (1972). The Wealth of India. Raw Materials. Vol. 9. New Delhi, India: Council of Scientific and Industrial Research.

LEMMENS, R.H.M.J. and WULIJARNI - SOETJIPTO, N. (1991). Plant Resources of South-East Asia. Wageningen, Holland: Pudoc/Prosea.

MCLAREN, K. (1983). The Colour Science of Dyes and Pigments. Bristol, UK: Adam Hilger Ltd.

ROBERTSON, S. (1973). Dyes from Plants. New York: Van Nostrand Rheinhold Co.

SASTRI, B.N., editor (1950). The Wealth of India. Raw Materials. Vol. 2, pp. 84-88. New Delhi, India: Council of Scientific and Industrial Research.

SUZUKI, H. and MATSUMOTO, T. (1988). Anthraquinone production by plant cell culture, pp. 237-250. In: Medicinal and Aromatic Plants, edited by Y.P.S. Baja. Berlin: Springer Verlag.

TEWARI, D.N. (1994). Tropical Forest Produce. Dehra Dun, India: Int. Book Distributors.

MARIGOLD (TAGETES)

Summary of Basic Information


Usage:  (a) Major - yellow colourant additive to poultry feed;
(b) minor - colourant for human foodstuffs.
Common names for products: (a) "Marigold meal" and "Aztec marigold" for the dried, powdered flowers; and
(b) "marigold extract" for the solvent extract of the flowers.
Raw material source: Flowers of an annual herb.
Botanical source: Tagetes erecta L. (family: Compositae).
Common name for botanical source: "Aztec marigold" in the Americas; "khaki bush" in Africa.
Distribution: Indigenous to Mexico, Central America and the Western Andes of South America. Widely introduced elsewhere in the world.
Form traded internationally:
  1. )The dried flowers (marigold meal),
  2. )organic solvent extracts, usually suspended in vegetable oils.
World production and trade: Unquantified; perhaps equivalent to 6,000 tonnes of meal.
Major exporters: Mexico and Peru.
Major importers: Mexico, Western Europe (especially Spain) and North America.
Availability of reliable published information: Moderate to fair.

Description and Colourant Uses

The common term "marigold" embraces a diversity of plants with golden flowers, including the Tagetes species of the Americas. The latter have been widely introduced throughout the world, some purely for decorative purposes and others for industrial use. For example, T. glandulifera Schrank and T. minuta L. are cultivated in southern Africa and India ? in addition to South America ? for the production of "Tagetes oil", an essential oil employed by the international perfumery industry; world demand for this oil is about 10 tonnes annually.

Another species, T. erecta L. or "Aztec marigold" provides an important yellow colourant from its flowers. This is produced on a significant scale only in the Americas. The principal pigment in the flowers is the xanthophyll, lutein, which is present in the form of esters of palmitic and myristic acids.
 
 








The principal use of Aztec marigold is as an additive, either in the form of the dried flower meal or as a solvent extract, to poultry feed in order to enhance the yellow colour of the flesh and the yolks of eggs.

There is a minor usage of the extract as a food colourant in Western Europe in products where a yellow colour is required, together with stability to heat, oxidation and SO2. Typical applications include: salad dressings, ice cream, dairy products and other foodstuffs with a high fat content, soft drinks, bakery products, jams and confectionery. The pigment is usually supplied as a liquid extract on an edible vegetable oil carrier at a concentration of 5 to 12% lutein and recommended dosage levels range from 0.05 to 0.8% (weight for weight) according to the application. Dispersed, powdered forms of the extract are also available. Although naturally derived lutein is embraced within the E161 classification in the European Community, marigold extract has not been assigned an "E number" and is traded as a "vegetable extract". It competes with lutein extracted from alfalfa grass.

Marigold extract is not currently approved for use as an additive to human foods in the USA.
 

World Demand and Supply Trends


Marigold meal is produced principally in Mexico, Peru, Ecuador, Argentina and Venezuela. More recently, smaller-scale producers include South Africa and Zambia. Apart from Peru, statistics on production and international trade in the meal and its extract are scanty and unreliable. However, total trade is probably equivalent to many thousand tonnes of meal annually. Peruvian exports alone were up to 3,000 tonnes of meal a year in the mid- to late 1980s.

There is a large trade within Latin America itself where marigold is widely employed in poultry feed. Mexico imports substantial quantities in order to supplement its domestic production and the needs of its extraction industry.

Other principal importers are North America and Western Europe, both in the form of meal and extract. The usage in the USA and in the major European importing countries, Spain and Portugal, lies in poultry feed. Elsewhere in Europe, the preference is for white chicken meat and yellow colour enhancement of egg yolks is most frequently achieved by incorporation of permitted synthetic dyestuffs in the feed.

The principal producer of the extract is Mexico with smaller-scale processing in Peru and some of the major import markets. South Africa and Zambia plan to produce the extract for the export market in the near future.

Usage of marigold extract as a colourant for human foodstuffs in Western Europe is presently very small. Total consumption by this sector of lutein pigments from all sources (marigold and alfalfa) has been recently estimated as less than 1 tonne a year. Any growth of food usage in developed countries will depend on trends in legislation and, specifically, a requirement for costly toxicological testing before being approved as a natural colour. Also, marigold's quality/price competitiveness with other natural lutein sources will be a significant factor in future usage.
 

Cultivation and Processing

Cultivation

T. erecta is an annual herb which prefers a warm, low humidity climate and grows well up to 500 m in the tropical Andes. Propagation is by means of seed and plant spacings are typically 20 cm x 90 cm.

Flowering commences 90 to 100 days from field establishment and harvesting of fully developed flowers is carried out regularly throughout the season.

Harvested flowers are sun- or shade-dried, depending upon facilities available and are then reduced to a powder prior to packaging for sale. Yields of meal in Peru have been reported as 1,000-1,200 kg/ha.

Extraction

Hexane is the most commonly used solvent for extraction. Prior to sale, the concentrate of the extract is either mixed with an edible vegetable oil or, when destined for poultry feed, it may be mixed with soya or corn meal. Anti-oxidants may be added to these products; the choice being dependent upon the end-use and permitted list in the end-market.
 

SELECTED BIBLIOGRAPHY


EL-BOUSHY, A.R. and RATERINK, R. (1992). Egg yolk pigmentation. World Review Animal Production, 27(1), 49-62.

DAMRON, B.L. et al. (1990). Marigold extracts and maize gluten meal as broiler pigment sources in maize and wheat-based diets. Animal Feed Sci. Technol., 31(1/2), 79-89.

FLETCHER, D.L. and HALLORAN, H.R. (1981). An evaluation of commercially available marigold concentrate and paprika oleoresin on egg yolk pigmentation. Poultry Sci., 60(8), 1846-1853.

GAU, W. et al. (1983). Mass spectrometric identification of xanthophyll fatty acid esters from marigold flowers (Tagetes erecta) obtained by high performance liquid chromatography and Craig countercurrent distribution. J. Chromatography, 262, 277-284.

GREGORY, G.K. et al. (1986). Quantitative analysis of lutein esters in marigold flowers (Tagetes erecta) by high performance liquid chromatography. J. Food Sci., 51(4), 1093-1094.

HENRY, B.S. (1992). In: Natural Food Colourants, edited by G.A.F. Hendry and J.D. Houghton. Glasgow: Blackie.

HOPPE, P.P. (1988). Pigmenting efficiency of marigold products examined in poultry. Feedstuffs, 60(18), 24-30 and 54-56.

LIVINGSTON, A.L. (1986). Rapid analysis of xanthophyll and carotene in dried plant materials. J. Assoc. Official Anal. Chemists, 69(6), 1017-1019.

MARMION, D.M. (1984). Handbook of US Colourants for Foods, Drugs and Cosmetics. New York: John Wiley and Sons.

PHILIP, T. and BERRY, J.W. (1976). A process for the purification of lutein-fatty acid esters from marigold petals. J. Food Sci., 41, 163-164.

TYCZKOWSKI, J.K. and HAMILTON, P.B. (1991). Preparation of purified lutein and its diesters from extracts of marigold (Tagetes erecta). Poultry Sci., 70(3), 651-654.
 

PAPRIKA

Summary of Basic Information


Usage:
  1. As a spice;
  2. as an orange-red food colourant.
Common names of products: (a) Sweet paprika; the powdered dry spices; (b) paprika oleoresin; the concentrated, solvent extract of the colour and flavour.
Raw material source: The fruits of an annual herbaceous plant.
Botanical source: Specific varieties of Capsicum annuum L. which have large, fleshy, intensely red coloured fruit and possess no pungency.
Common name for botanical source: Paprika; sweet red pepper.
Distribution: Widely cultivated throughout the world.
World production:
  1. Paprika - 45,000 tonnes (estimate)
  2. paprika oleoresin - 1,000 tonnes (estimate).
World trade:
  1. Paprika - 30,000 tonnes (estimate)
  2. paprika oleoresin - 700 tonnes (estimate).
Major exporters: Spain, Hungary and Morocco.
Major importers: Western Europe, North America, Eastern Europe and Japan.
Availability of reliable published information: Good.

Description and Food Colourant Uses


Paprika is obtained from the fruits of selectively bred varieties of "sweet peppers", Capsicum annuum L. The fruits are large, fleshy with an intense red colour and are devoid of, or contain very little of, the pungent ("hot") capsaicinoid compounds which characterise most other species and varieties of Capsicum. In commerce, paprika is always a dried, ground product but a small international trade between growers and grinders does exist in dried, unmilled fruit pods. Products termed "hot paprika" are marketed but these are strictly variants of the UK's "chili powder" and the "red pepper" of the USA in which a high colouring power is combined with a mild pungency.

While being a source of red-orange colouring in culinary applications, sweet paprika also possesses a distinctive, much appreciated aroma and flavour and it is classified as a spice. Paprika plays an important role in the cuisine of Spain and Hungary (e.g., Hungarian goulash); the two European countries where production of the variety developed on a major scale following the introduction of Capsicum species from the Americas in the sixteenth century.
 
 








The pigments present in paprika are a mixture of carotenoids, in which capsanthin and capsorubin dominate. These are oil-soluble, stable to heat and pH variation but deteriorate in light.

Extraction of paprika with organic solvents provides paprika oleoresin which is a concentrated form of the pigments and the flavour. The oleoresin is employed as an alternative to the spice in the industrial preparation of sausages, meats, soups and pickles and in other savoury products, such as snack foods and breadcrumbs. The presence of the flavour in most commercial oleoresins restricts the scope of application as a food colour in a number of other products, e.g., confectionery and desserts. The colour imparted by the oleoresin ranges from red to orange, depending upon the concentration used. Commercial oleoresins are available in strengths ranging from 40,000 to 100,000 ASTA (American Spice Trade Association) colour units; the strongest type has a pigment content of approximately 10%. The oleoresins are oil-soluble and normally are sold as solutions in edible vegetable oil. Water-miscible forms of the oleoresin are also available and these incorporate polysorbates or are emulsions with gum arabic.

Paprika extract/oleoresin is listed by the European Community as a natural colour which is permitted for use in foods and it has been assigned the number E160(c). In the USA, paprika oleoresin is also included in the Food and Drug Administration's list of approved natural colours for incorporation in foods and beverages.

World Demand and Supply Trends

Paprika is a spice with very specific geographical markets, namely Eastern and Western Europe, the Mediterranean, North America, Argentina and Chile. Elsewhere in the world, demand is for the pungent or "hot" types of capsicums (i.e., chillies).

Accurate assessment of the world production and trade in both paprika and its oleoresin is plagued by problems of the classification systems employed in official statistics. In the case of the spice, paprika, it is usually combined in export and import statistics together with pungent capsicums (chillies), frequently with allspice/pimento, and occasionally with pepper. Paprika oleoresin is similarly combined with other spice oleoresins in published trade statistics for many countries. It is only in the USA import data that paprika and its oleoresin are distinctly identified.

The size of the international trade in paprika in the late 1970s was estimated as somewhat in excess of 30,000 tonnes per annuum with Spain and Hungary as the major exporters and Bulgaria, Yugoslavia and Morocco as significant secondary sources. Western Europe was the largest market, accounting for around 50% of world imports. At that time, USA imports were of the order of 4,000-5,000 tonnes annually which was much less than its domestic production of paprika. Additionally, world paprika oleoresin production was estimated as between 400-500 tonnes annually, of which the bulk was manufactured within the major paprika growing countries (Spain, USA and Hungary). Total world production of paprika in the late 1970s, therefore, was probably around 40,000 tonnes per annum.

In the subsequent period, there has been a global growth in the consumption of both paprika and its oleoresin, together with an increase in the number of suppliers. Western Europe remains the largest import market with a demand for paprika approaching 20,000 tonnes annually in the early 1990s. Notably also, Spain has commenced to import significant volumes of paprika from diverse sources to supplement its domestic production and to maintain its dominant role in the global trade. Imports of paprika by the USA in the same period were around 4,000 tonnes annually with Spain and Morocco as its major suppliers. Total paprika consumption in the USA now appears greater than that of Western Europe on summing imports and domestic production. Other significant scale markets for paprika include Japan and a number of Eastern European and North African countries.

The USA is a major producer of paprika oleoresin but also has imported 300-400 tonnes annually in the first half of the 1990s, sourcing mainly from Spain and Morocco. Western European consumption of paprika oleoresin is difficult to quantify but is very substantial. The best possible educated guess at global demand for paprika oleoresin in the mid-1990s is 1,000 tonnes or more annually.

The past decade has seen the development of production of paprika and its oleoresin outside the "traditional" areas of Europe, the USA and North Africa. New suppliers to the market include Mexico, Chile, Argentina, Peru, Ethiopia, South Africa, Zimbabwe, Zambia, Malawi, Israel and India.

Production of paprika in Southern Africa averaged 20,000 tonnes annually over 1992-1994 and the installed processing capacity in the region in 1995 was around 250 tonnes of oleoresin per annum.

While the market has expanded and there have been some recent production problems in Spain and Hungary, it is possible that the future will see a period of increasing competition between producers and perhaps a significant change in the relative importance of individual sources.

Paprika prices displayed a growth trend during the 1970s. Spanish material on the New York market moved from US$ 0.8/kg to US$ 1.8/kg (cif) and stabilised at the latter price for a couple of years. The more recent period has seen rather greater price swings with average annual New York prices (cif) for imported paprika declining from US$ 2.0/kg to US$ 1.45/kg over the three years 1992-1994. The average annual unit value (US$/kg) of imported paprika oleoresin on the New York market over 1992-1994 fluctuated from 41.5 to 36.1 and then up to 47.4. For both paprika and its oleoresin, there is a significant differential in price according to its quality as judged primarily on its colouring power and tone.
 

Cultivation and Processing

Climate and Soils

Traditionally, paprika is a summer, annual crop of continental temperate and sub-tropical, and Mediterranean climates. However, some varieties may be grown in tropical climates.

Temperatures of 15-24?C are preferred, together with limey, well-drained, loam soils. It is usually a rainfed crop in areas with 60 to 1,250 mm of rainfall per year.

Propagation, Husbandry and Harvesting

Plants are raised from selected seed and care must be taken in the choice of the appropriate cultivar, both for end-product quality and field performance. Most European cultivars do not translate well to tropical conditions. Additionally, seed propagation nurseries in the tropics must be sited well away from any cultivation of pungent chillies since Capsicum species readily cross-pollinate. If this occurs, the new generation paprika strain would deteriorate in quality by acquiring pungency and losing colour power.

Field spacing is commonly 0.5 m x 1 m and weeding is an important activity in the early phase of husbandry. The interval between sowing and the first fruit setting is usually three months and harvesting can span 3 months.

Fruits are picked individually when they reach maturity, i.e., fully coloured and either still succulent or just beginning to wither. They are then dried either in the sun or by artificial methods. For sun-drying, the fresh fruits are usually cut open prior to spreading on a clean surface or to hanging in string bags. Achievement of the dry state (10-12% moisture content) can take between 8 to 15 days in the sun. Artificial drying is performed at 60-65?C on sectioned or diced fruits.

Yields of dried pods range from 2.5 tonnes/ha under rainfed conditions to 6 tonnes/ha or more with irrigation and careful management.

Exporters of unprocessed paprika first separate the seed, calices and peduncles from the dried pods. The pods are then compressed and bagged for shipment in containers.
 

Production of Paprika Powder

Only the pericarps and seeds are used to produce the paprika of commerce; placental tissue, calices and peduncles are discarded. The pericarp and seed are separated and each are washed since this assists removal of any pungent capsaicin which has migrated from the placental tissue.

Colour of the end-product is influenced by the content of seed mixed with the pericarp prior to grinding. "Select", bright red qualities of paprika contain no more than 10% seed while "ordinary" qualities contain up to 30% seed and possess a brick-red colour.

The paprika is sold by grade quality, as judged visually and objectively on the American Spice Trade Association (ASTA) colour scale. Shipment is in cardboard drums, lined with a polythene bag.
 

Oleoresin Processing

Extraction of paprika is undertaken with conventional spice oleoresin equipment, either on a batchwise or a continuous process, and employing an organic solvent (normally hexane). Extracts are concentrated and yields range considerably from about 5 to 12%, depending on the raw material quality and the solvent used.

Extracts are blended prior to sale to provide a standardized colouring power on the ASTA American Spice and Trade Association) scale.

A unique process is employed in Ethiopia as a matter of expediency since the raw material feedstock is not sweet paprika but an indigenous, highly pigmented but pungent capsicum. The extract is subjected to countercurrent treatment between apolar and polar solvents and the pigments separate into the former while the capsaicinoids are taken up by the latter.
 

SELECTED BIBLIOGRAPHY

Production and Markets

ASTA (1995). The ASTA Report: Spice Consumption '93 - Imports, US Production, Current Trends. Englewood Cliffs, N.J., USA: The American Spice Trade Association.ont>

ITC (1982). Spices - A Survey of World Markets. (2 volumes). Geneva, Switzerland: International Trade Centre.

ITC (1986). Essential Oils and Oleoresins: A Study of Selected Producers and Major Markets. Geneva, Switzerland: International Trade Centre.

ITC (1992). Imports of spices into selected markets, 1987-1991, pp. 275-376. In: Report of Third Meeting of the International Spice Group, Kingston, Jamaica, 18-23 November 1991. Geneva, Switzerland: International Trade Centre.

SMITH, A. (1982). Selected Markets for Chillies and Paprika. Tropical Products Institute Report no. G155; available from the Natural Resources Institute, Chatham Maritime, UK.

USDA (1995). US Spice Trade, pp. 38-82. In: Tropical Products: World Markets and Trade. Washington DC: United States Department of Agriculture Foreign Agricultural Service Circular Series FTROP 1-95, April 1995.

Cultivation, Processing, Quality Control and Food Applications

ASTA (1987). Clean Spices: A Handbook for Members. Englewood Cliffs, N.J., USA: American Spice Trade Association.

ASTA (1992). ASTA Cleanliness Specifications for Unprocessed Spices, Seeds and Herbs. Englewood Cliffs, N.J., USA: American Spice Trade Association.

GOVINDRARAJAN, V.S. (1986). Capsicum - production, technology, chemistry and quality. CRC Critical Reviews in Food Sci. Nutrition, 23(3), 207-288.

HENDRY, G.A.F. and HOUGHTON, J.D. (1992). Natural Food Colourants. Glasgow, UK: Blackie.

MARMION, D.M. (1984). Handbook of US Colourants for Foods, Drugs and Cosmetics. New York: John Wiley and Sons.

MINGUEZ-MOSQUERA, M.I. and HORNERO-MENDEZ, D. (1993). Separation and quantification of the carotenoid pigments in red peppers, paprika and oleoresin by reversed phase HPLC. J. Agric. Food Chem., 41(10), 1616-1620.

PURSEGLOVE, J.W. et al. (1981). Spices, Vol. 1. Harlow, UK: Longman Group Tropical Agriculture Series.

ROSENGARTEN, F. (1969). The Book of Spices. Wynewood, Penn., USA: Livingstone Press.

SOMAS, A. (1984). The Paprika. Budapest, Hungary: Akademini Kiado.

TAINTER, D.R. and GRENIS, A.T. (1993). Spices and Seasonings: A Food Technology Handbook. New York: VCH Publishers Inc.
 

SAFFLOWER

Summary of Basic Information


Usage:
  1. Formerly as a red dyestuff for textiles; and
  2. currently as a minor colourant by the food industry.
Common name for product: Safflower; dyer's saffron.
Raw material source: The florets of a cultivated, annual herb. 
Botanical source: Carthamus tinctorius L. (family: Asteraceae).
Common names for botanical source: Safflower; bastard saffron; false saffron; dyer's saffron; distaff thistle; dyer's thistle.
Distribution: Widespread through tropics and sub-tropics.
Form traded internationally: Dried florets.
World production and trade: Small, unquantified.
Major exporters: India, Pakistan and China.
Major importers: West European countries.
Availability of reliable published information: Limited on the dyestuff/colourant; good on the seed and its oil.

Description and Dyestuff/Colourant Uses

Safflower (Carthamus tinctorius L.) is an annual herb which is well adapted to semi-arid conditions in the tropics and sub-tropics. It is a thistle-like plant with a deep taproot, growing up to 120 cm high, with a branched stem and a flower head at the end of each branch.

The florets contain three major pigments, all of which are present as chalcone glucosides: the water-insoluble scarlet-red carthamin and the water-soluble "safflor yellow" A and B. The latter pigments are deliberately removed by water washing in the traditional primary processing of the florets in order to provide the desired, red raw material for dyeing/colourant usage.

Safflower was formerly employed, as its synonym "dyer's saffron" implies, as an inexpensive substitute for saffron in textile dyeing. The term "red tape" originates from the use of safflower to impart a pink-red colour to the tape employed to bind legal documents. The colour tone can be varied according to the mordant used through pink, red, rose, crimson to scarlet.

Today, dyestuff usage of safflower is limited to traditional applications in countries such as India. It is offered as a food colourant in some developed countries under the description of a "natural vegetable extract". Toxicological clearance has not yet been secured in the European Community for assignment of an "E number" as an approved natural colourant; nor is it listed under the US Food and Drug Administration's permitted list of natural colours for foods and beverages.

The major purpose of cultivating safflower globally is for the production of its seed and further processing to its edible fatty oil. The latter is a highly regarded, polyunsaturated type and receives a premium on the world market.
 
 

World Demand and Supply Trends

Safflower is widely grown through the tropics and sub-tropics as an oilseed crop and production of seed is estimated to range between 0.8 and 1.0 million tonnes annually. The major oilseed producers in descending order of importance are Mexico, India and the USA. International exports of safflower seed oil are dominated by the USA and Australia. Literature on this subject abounds.

By comparison with the oilseed product, cultivation for the florets as a dyestuff/colourant raw material today is a very minor activity which is poorly documented. India is probably the main source but its export statistics reveal annual shipments of no more than 15 tonnes between 1988-93.

As with a number of other natural colourants, interest in safflower has been expressed by some sectors of the food industries in developed countries in recent years. However, the extent of future usage will depend on the ultimate, legislative requirements for safety clearance of new food additives, especially as a food colour where high dosage may be necessary to achieve the desired colour. The perceived comparative advantage of safflower over competing materials in specific applications will be a factor also. Any growth in demand probably could be readily served by existing producers in Asia.
 
 

Cultivation and Processing

Cultivation Requirements

Safflower can be grown in a wide range of ecological conditions between 30-45? north and 15-35° north. However, it is generally regarded as a semi-arid region crop and is often grown in rotation with wheat or cotton in the winter-spring period. Growth performance is best on neutral to alkaline soils which are well-drained and fertile. Rainfed culture is common but irrigation provides the highest yields.

Propagation is by means of seeds. In rainfed arid environments, seeding rates are 8-10 kg/ha while 15-20 kg/ha may be used under irrigated conditions. Weeding is important to ensure high yields.

There are many varieties of safflower and in India a distinction is made between those with spinous leaves and the comparatively spineless. The latter type are considered superior for dyestuff/colourant production.

The first florets are removed immediately after their appearance in order to encourage branching and the formation of additional florets. Harvesting of the florets must be carried out regularly, usually every second or third day, in order to obtain fully opened flowers but before withering and seed formation occurs. Drying is undertaken in the shade to prevent light degradation of the pigments. Dried floret yields in India have been reported as 50 to 75 kg/ha.

Processing of the Dyestuff

The traditional Indian method of processing the dried florets commences with removal of the water-soluble yellow pigments. This involves repeated washing in acidulated water over several days. The water-washed florets are dried, often being compressed into a cake prior to sale. For dyeing or colourant use, this material is treated with aqueous sodium carbonate and the extract is acidified to yield a precipitate which is sold as a paste. The content of carthamin in Indian safflower florets has been reported to range from 0.3 to 0.6%.

Improved methods for extraction of carthamin from safflower and of alternative production by tissue culture have been reported in recent years, mainly by Japanese researchers.

SELECTED BIBLIOGRAPHY

On the Dyestuff/Colourant


DEAN, F.M. (1963). Naturally Occurring Oxygen Ring Compounds. London: Butterworths.

FRANCIS, F.J. (1992). Pp. 258-260. In: Natural Food Colourants, edited by G.A.F. Hendry and J.D. Houghton. Glasgow: Blackie.

HANAGATA, N. et al. (1994). Effect of medium in first stage culturing on red pigment formation in suspension culture of Carthamus tinctorius. J. Biotechnol., 34(2), 213-216.

OBARA, H. and ONDERA, J. (1979). Structure of carthamin. The red colouring matter of the flowers of safflower. Chem. Lett. (Chem. Soc. Japan), Feb.(2), 201-204.

ROBERTSON, S. (1973). Dyes from Plants. New York: Van Nostrand Reinhold Co.

SAITO, K. and FUKUSHIMA, A. (1989). Apparent expression of flower colours and internal variation of enzyme activities in some typical phenotypes of dyer's saffron cultivars. Acta Soc. Botanicorum Poloniae, 58(4), 593-603.

SAITO, K. (1991). A new method for reddening dyer's saffron (Carthamus tinctorius) florets: evaluation of carthamin productivity. Zeitschrift Lebensmittel Untersuchung Forschung, 192(4), 343-347.

SAITO, K. and KAWASAKI, H. (1992). Comparative studies on the distribution of quinoidal chalcone pigments in extracts from insect wastes and intact tissues of dyer's saffron florets. Zeitschrift Lebensmittel Untersuchung Forschung, 194(2), 131-133.

SAITO, K. (1993). A new enzymatic method for extraction of precarthamin from dyer's saffron (Carthamus tinctorius) florets. Zeitschrift Lebensmittel Untersuchung Forschung, 197(1), 34-36.

SAITO, K. and MIYAKAWA, K. (1994). A new procedure for the production of carthamin dye from dyer's saffron flowers Lebensm. Wiss. Technol, 27(4), 384-385.

SATSTRI, B.N., editor. (1950). The Wealth of India. Raw Materials. Vol. 2, pp. 84-88. New Delhi, India: Council for Scientific and Industrial Research.

TAKAHASHI, Y. et al. (1982). Constitution of two colouring matters in the flower petals of Carthamus tinctorius L. Tetrahedron Letters, 23(49), 5163-5166.

TAKAHASI, Y. et al. (1984). Chemical constitution of safflor yellow B from the flower petals of Carthamus tinctorius L. Tetrahedron Letters, 25(23), 2471-2474.

TEWARI, D. N. (1994). Tropical Forest Produce. Dehra Dun, India: Int. Book Distributors.

WAKAYAMA, S. (1988). Production of pigments of Carthamus tinctorius by tissue culture. Nyu Fudo Indasutori, 30(4), 7-9. (In Japanese).

Safflower Seed and Oil

JOHNSON, A. and MARTER, A. (1993). Safflower Products: Utilisation and Markets. Chatham, UK: Natural Resources Institute Marketing Series No 6.

ROBBELEN, G. et al. (1989). Oil Crops of the World: Their Breeding and Utilization. New York: McGraw Hill.

SALUNKE, D.K. et al. (1992). World Oilseeds: Chemistry, Technology and Utilization. New York: Van Nostrand Rheinhold.
 

TURMERIC

Summary of Basic Information


Usage:
  1. As a spice;
  2. as a yellow colourant for foodstuffs.
Common names for the products:
  1. Turmeric or curcuma for the spice;
  2. turmeric oleoresin for the concentrated extract;
  3. "pure curcumin" for the refined oleoresin, free of volatile oil.
Raw material source: The rhizomes, particularly the "finger" side-growths of a perennial herbaceous herb.
Botanical source: Curcuma domestica Val. (syn. C. longa Koenig non L.; family: Zingiberaceae).
Common names for botanical source: Turmeric; curcuma.
Distribution: Widespread throughout the tropics.
Product forms traded internationally: Whole and powdered spice; the oleoresin and "pure curcumin".
World production: Not quantified for the spice but possibly tenfold or greater than international trade.
International trade:
  1. 15,000-20,000 tonnes per annum for the spice
  2. 100-150 tonnes for the oleoresin
Exporters: India (dominant), China and numerous smaller suppliers in Asia, Latin America and some in Africa.
Major importers: Iran, North America, Western Europe and Japan.

Description and Colourant Uses

Turmeric is a small perennial herbaceous plant with a tuber, bearing many rhizomes or "fingers" which are aromatic and pigmented yellow orange-red. The plant originates from the Indian sub-continent and possibly neighbouring areas of Southeast Asia but it is now widely grown throughout the tropics as an annual. The usage today is as a spice and a food colourant but it was formerly employed also as a yellow dyestuff for textiles.

The turmeric of commerce consists of the dried finger rhizomes and these vary in size from 2.5 to 7.5 cm in length and possess a diameter of approximately 1 cm. Breaking the dried fingers reveals a pigmented interior which can range in colour from yellow to reddish-orange, depending upon the pigment content (2 to 7% in commercial material). The rhizomes contain also a volatile oil with a characteristic aroma and flavour which varies in abundance according to the cultivar. Good commercial turmeric has a 1:1 ratio of oil to pigment (weight for weight).

Three principal pigments are present in the rhizomes: curcumin, desmethoxycurcumin and bis-desmethoxycurcumin; these are collectively known as curcuminoids. They are found also in other Curcuma species.

As a spice, turmeric is valued for the combination of flavour and yellow colouring power. It is an essential ingredient of many curry recipes and it is in this application that usage is greatest on a global basis. Colouring of rice, usually as an inexpensive alternative to saffron is another widespread use.

In Western Europe and North America, turmeric is employed for a range of food colouring purposes, notably in mustard. Today, food manufacturers employ the oleoresin of turmeric, the concentrate of the solvent extract, to a greater extent than the powdered spice. The volatile oil content can be reduced in the processing of the oleoresin and this reduces the aroma impact in applications where the primary objective is colouring. "Pure curcumin" (95% curcuminoid content) is also available but this is less frequently used. Applications of the oleoresin and curcumin range from sugar confectionery, ice cream, dry mixes for puddings and drinks and pickles. Colours range from lemon in acidic media to orange in alkalis.

The oleoresin is oil-soluble, while pure curcumin is less oil-soluble and both are insoluble in water. Incorporation of a food grade solvent and emulsifier, usually polysorbate, in the oleoresin provides a water-soluble product.

Turmeric, its oleoresin and curcumin are universally permitted as food additives. In the European Community, curcumin from turmeric is included in the natural colour list as E100 while turmeric and its oleoresin are on the US Food and Drug Administration's approved natural colour list for foods and beverages.

World Demand and Supply Trends

Turmeric is grown widely throughout the tropics and it is not possible to accurately quantify world production since the bulk is consumed domestically rather than entering international trade. In the case of the world's largest grower, India, annual production fluctuates widely but has averaged 390,000 tonnes in the recent period, of which no more than 5% is exported (between 8,000 and 20,000 tonnes from year to year) and this represents the surplus over domestic demand.

The scale of annual world trade for the turmeric spice is estimated as between 15,000-20,000 tonnes while the demand for turmeric oleoresin and pure curcumin is perhaps 150 tonnes. India is the dominant exporter of both the spice and of the oleoresin, supplying 60% or more of the two markets in most years. In the case of the oleoresin, India has effectively captured the market in Western Europe from former domestic processors of the imported spice and only the USA still manufactures a substantial proportion of its oleoresin requirement. Nevertheless, the USA is India's major market for the oleoresin and takes about 90 tonnes annually.

China is second in the world league as a supplier of the spice while in the third rank there are a number of other countries in the Indian sub-continent, Southeast Asia, the Caribbean and Latin America. None of these are of significance as oleoresin suppliers.

The major world markets for the spice are Iran, Western Europe (especially the UK and Germany), North America and Japan. Numerous other countries are smaller-scale importers.

All of the major markets are characterised by distinct preferences for quality characteristics of the spice. Most prefer the "Madras" type which is yellow coloured and moderately pigmented, containing up to 3.5% of curcuminoid pigments. The best quality of Madras is exported by India, where the name originated, although the Chinese equivalent has gained a high regard in recent years. A second type, known as "Alleppey" turmeric after the port of export of this material in India, is highly pigmented, containing between 4.5 and 6.5% curcuminoid pigments. This is the type of choice for oleoresin extraction and has always been preferred in the USA, where it accounts for 90% of the average annual spice import of 2,000 tonnes. India again is the dominant supplier of the Alleppey type of turmeric, both in terms of volume and the highest quality. Thailand supplies a fair quality Alleppey type material, while highly pigmented but poor colour-tone material is exported by several countries in the Caribbean and South America, notably Jamaica, Haiti and Peru. Japan now imports principally a special Indian quality known as "Rajpuri".

International market prices for turmeric are set by the size of India's crop and the volume available for export. Indian Alleppey turmeric commands a premium over the Indian Madras type in most years and the differential is often a factor of two. On the major market for Alleppey turmeric, i.e., the USA, price differentials are paid also according to the curcumin content over its range from 4.5 to 6.0%. Between 1985 and 1994, New York annual average spot market prices for Indian Alleppey turmeric with a 5.5-6.0% curcumin content fluctuated between US$ 1.2-2.5/kg. In the same period, Thai turmeric of comparable curcumin content was usually discounted by 15% and the discount on Peruvian material was on average 30%. For Madras type turmeric, China has in most years priced well below India in order to increase its market share.

Future market trends are expected to differ according to their geographical location. Demand for turmeric in developed countries is likely to grow only modestly. By contrast, a continual increase in consumption is expected in Asia along with population growth. This could lead to shortages, particularly of high quality material, owing to the present high dependence upon India. While many countries have the potential to expand production to meet any emergent supply gap, the present quality of their products is very mediocre and this is primarily the consequence of intrinsic deficiencies in their planting stock. Success on the market will be dependent first on the introduction of superior cultivars, either Madras or Alleppey types; the former presents the greater market opportunity in terms of scale of demand.

The prospects for new producers of turmeric oleoresins are not great in the medium term in view of the existing competitiveness of the market and the established, dominant position of India. Profitability could be ensured only by operating the equipment at close to maximum capacity by production of a range of spice oleoresins, using high quality raw materials.
 

Photo N.1: Turmeric (curcuma domestica) cultivation, Solomon Islands. (Photo: NRI)

Photo N.2: Turmeric "fingers". (Photo: NRI)
 

Cultivation and Processing

Climate and Soil Requirements

Turmeric thrives in a hot, moist tropical climate with rainfall of 1,000-2,000 mm. It prefers a rich well-drained loam soil. Cultivation is possible from sea level up to about 1,500 m.

Cultivation

Propagation is by means of pieces of the lateral rhizomes which are detached from a plant at harvest time. They are stored under leaves or soil for two to three months until the commencement of the planting season.

Planting is often made on ridges to aid subsequent harvesting and spacing is usually 20?40 cm.

Harvesting is undertaken when the leaves wither and this varies from 9-12 months of age, depending on the cultivar and the site.

The rhizomes are lifted, detached from the stems and then washed. The secondary lateral shoots' "fingers" are then separated from the bulbous material; the latter is either rejected or used to prepare low grade spice for the local market.

Primary Processing

This involves boiling the fingers in water, followed by drying in the sun. The boiling step is advantageous in uniformly dispersing the pigment and, also, gelatinising the starch, which facilitates rapid drying and provides a protection against insect attack during storage. Boiling is carried out for 1 to 4 hours and sun-drying may take up to fifteen days.

Moderately pigmented cultivars ? the Madras type ? by tradition have the outer fibrous skin removed prior to sale. This "polishing" operation can be accomplished by abrasion in a simple rotating drum. The highly pigmented, "Alleppey" types are not normally polished.

Dried spice yields vary according to cultivar and site from about 0.4 to 1.7 tonnes/ha.

Oleoresin and Curcumin Production

The oleoresin may be prepared by the standard procedure for spices of sequential extraction of the ground material in an organic solvent, followed by solvent stripping. Yields of 8 to 12% have been reported.

"Pure curcumin" is obtained by crystallization from the oleoresin, followed by sequential recrystallization to remove volatile oil and other plant extractives.

Other Uses

Turmeric has played a traditional role as a crude dyestuff and cosmetic in many societies but these applications are now minor. Usage in traditional medicine continues in Asia and interest has been expressed by some researchers in the potential within modern medicine. In particular, some attention has been given to the antimicrobial and antifungal activity of turmeric oil which is a by-product of oleoresin processing in India and has a very limited market demand at present. Prospects for commercial success in this area are probably slight.

Research and Development Needs

For the majority of countries which wish to develop production and exports of turmeric, the priority must be planting stock quality improvement. Selection must be made of cultivars with the appropriate curcumin content and colour tone for either the Madras or the Alleppey markets while avoiding an excessive volatile oil content; the latter is a common problem in many countries. Where insufficient variability is present in the indigenous resource, introductions of superior cultivars from elsewhere will be necessary.

A second area of recommended research for some countries is an appraisal of the potential of turmeric within agroforestry systems. The plant originated on the forest verge and has a degree of shade tolerance which lends it to incorporation in a mixed cropping system with shrubs and young trees.
 

SELECTED BIBLIOGRAPHY


ASTA (1995). The ASTA Report: Spice Consumption '93. Imports, US Production, Current Trends. Englewood Cliffs, N.J., USA: American Spice Trade Association.

ITC (1982). Spices - A Survey of the World Market. (2 volumes). Geneva, Switzerland: International Trade Centre.

ITC (1992). Imports of spices into selected markets, 1987-1991, pp. 276-376. In: Report of the Third Meeting of the International Spice Group, Kingston, Jamaica, November 1991. Geneva, Switzerland: International Trade Centre.

SMITH, A. (1982). Selected Markets for Turmeric, Coriander Seed, Fenugreek Seed and Curry Powder. Tropical Products Institute Report G165; available from Natural Resources Institute, Chatham Maritime, UK.

USDA (1995). US Spice Trade. In Tropical Products: World Markets and Trade. Washington DC: United States Department of Agriculture Foreign Agricultural Service Circular Series FTROP 1-95, April 1995.

Cultivation, Processing and Quality Control

ASTA (1987). Clean Spices: A Handbook for Members. Englewood Cliffs, N.J., USA: American Spice Trade Association.

ASTA (1992). ASTA Cleanliness Specifications for Unprocessed Spices, Seeds and Herbs. Englewood Cliffs, N.J., USA: American Spice Trade Association.

FRANCIS, F.J. (1992). Pp. 256-258. In: Natural Food Colourants, edited by G.A.F. Hendry and J.D. Houghton. Glasgow, UK: Blackie and Sons.

GEORGE, K.M. (1981). On the extraction of oleoresin from turmeric - comparative performance of ethanol, acetone and ethylene dichloride. Indian Spices, 18(2-4), 7-9.

HENRY, B.S. (1992). Pp. 68-73. In: Natural Food Colourants, edited by G.A.F. Hendry and J.D. Houghton. Glasgow, UK: Blackie and Sons.

MARMION, D.M. (1984). Handbook of US Colourants for Foods, Drugs and Cosmetics. New York: John Wiley and Sons.

NAIR, M.K. et al., editors (1982). Proceedings of the National Seminar on Ginger and Turmeric, Calicut, India, April 1980. Kasaragod, Kerala, India: Central Plantation Crops Research Institute.

PURSEGLOVE, J.W. et al. (1981). Spices. Vol. 2. Harlow, UK: Longman Group, Tropical Agriculture Series.

TAINTER, D.R. and GRENIS, A.T. (1993). Spices and Seasonings. A Food Technology Handbook. New York: VCH Publishers Inc.

TAYLOR, S.J. and MCDOWELL, I.J. (1992). Determination of the curcuminoid pigments in turmeric (Curcuma domestica Val.) by reversed-phase high performance liquid chromatography. Chromatographia, 34(1/2), 73-77.

 
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