Ginger
Ginger is one of the five most important major spices of India. It is believed that ginger is native of southern Asia. According to available historical records, ginger was certainly known to Europeans and highly esteemed by the ancient Greeks and Romans who obtained this spice from the Arabian traders. It was introduced into Germany and France in the ninth century and to England in the tenth century. Since the ginger rhizome can be easily transported in a living state for a considerable distance, the plant has been introduced in many tropical and sub tropical countries. The important ginger producing countries are India, Jamaica, Sierra Leone, Nigeria, Southern China, Nepal, Pakistan, Japan, Taiwan, Australia, Mauritius, Malaysia and Indonesia. Of these Jamaica and Sierra Leone produce superior quality ginger followed by Nigeria. India and China are the two major suppliers of ginger in the world market. The major buyers of Indian ginger are the middle east countries, USA and West European countries. However from 1987-88 onwards the export has decreased mainly due to the fact that the production of the exportable variety of ginger in Kerala has shown a deep decline and consequently the domestic price has increased. There has been stiff competition from China as Well.
Kerala contributing one third of ginger production is the leading state in area and production of ginger in India. Meghalaya is the second leading state followed by Orissa, West Bengal. Andhra Pradesh, Karnataka, Sikkim, Mizoram, Madhya Pradesh, etc. In other like Bihar, Gujarat Haryana, Himachal Pradesh and some North Eastern States, it is also grown on a limited scale.
Composition
The dried rhizome of ginger is used as a spice hence the nutritive value of rhizome is given per 100 g.
| Moisture |
6.9 g |
| Protein |
8.6 g |
| Fat |
6.4 g |
| Fibre |
5.9 g |
| Phosphorus |
0.15 g |
| Iron |
0.001 g |
| Food energy |
380 calories |
| Sodium |
0.03 g |
| Potassium |
0.4 g |
| Vitamin A |
175 IU |
| Vitamin B1 |
0.85 mg |
| Vitamin B2 |
0.13 mg |
| Niacin |
1.9 mg |
| Vitamin C |
12.0 mg |
It is evaluated 30 ginger varieties for qualitative attributes and concluded that crude fibre content varied from 3.5 per cent in var. Tura to 6 per cent in var. Jorhat. Their findings showed that varieties having high dry ginger recovery had low fibre content and vice-versa. Oleoresin content varied widely among the types ranging from 3.0 per cent in var. Poona to 10.8 per cent in Rio-de-Janeiro. Oil content of recently release varieties viz: Suprabha, Suruchi and Surabhi varies from 1.9 to 2.1 per cent.
Uses
In food Preparations: The aroma of ginger is pleasant and spicy and its flavour penetrating, slightly biting due to antiseptic or pungent compounds present in it, which make it indispensable in the manufacture of a number of food products like ginger bread, confectionery, ginger ale, curry powders, certain soft drinks like cordials, ginger cocktail, carbonated drinks, bitters, etc. Ginger is also used for the manufacture of ginger oil, oleoresin in, essences, tinctures, etc.
Ginger Candy/Preserve: Ginger preserve and ginger candy prepared from green or fresh ginger are quite a favourite of many and find great demand.
Recovery of Starch and Soft Drinks from Spent Ginger: The author developed a number of useful products from spent or exhausted ginger (after the recovery of volatile oil) such as vitaminised effervescent ginger powder, vitaminised ginger powder, plain effervescent ginger powder. Likewise, the author suggested the recovery of starch from ginger residue left after the recovery of oleoresin. The integrated process for recovery of oleoresin, protein and starch recommended by the author is worth commercial exploitation.
Alcoholic Beverages: A number of alcoholic beverages are prepared from ginger in foreign countries, such as ginger brandly, ginger wine ginger beer and ginger ales, etc.
In Medicine: According to the Ayurvedic medical system, ginger is considered to be carminative, stimulant and given in dyspepsia and flatulent colic. It is also prescribed as an adjunct to many tonic and stimulating remedies. It also has aphrodisiac values, besides its use in tinctures and as a flavourant.
Botany
It is herbaceous perennial with underground tuberous aromatic stems (rhizomes) which are used both as spice and medicine. The ariel leafy sheets are about 50 cm and the leaf blades are long and narrow. The inflorescence is normally borne on a separate stem arising directly from the rhizome. The flowers are bisexual. The flowering started in October and continued till early December, the peak period being November. The flowers start opening at about 3 PM and anthesis occur simultaneously. It takes about 20-25 days from bud initiation to full bloom and 23-28 days to complete flowering. The fruit, which is very rarely produced, is in the form of a thin walled capsule containing a number of small, black angular seeds. Ginger (Gingiber officinale) belings to zingiberacea family.
Much work has yet to be done for evolving cultivars possessing high yield, low fibre content, high oleoresin content and resistance to soft rot disease. Research studies on genetic variability and heritability indicate that straight selection are beneficial to improve the characters of the ginger plant.
Climate and Soil
Ginger grows well in tropical and subtropical climates. It requires warm and humid climate for commercial production. It is grown successfully at sea level in the South to an altitude to 1000 m in the North-eastern region of India with an annual rainfall of 1500-3000 mm. It is suggested that ginger planting starts in early April at an altitude of 1600 m and 2 weeks later for 300 m reduction in altitude. The temperature requirements varies from 20 to 30°C for normal growth and production. It can resist a high temperature of 35°C. Beyond this level it start of scorching. In the high rainfall tract of Kerala and the North Eastern Hill region it is successfully grown as a rainfed crop while in other states few irrigations are given for commercial production during October-November. It thrives well under partial shade, hence it can be grown as an intercrop as well as a main crop in open conditions.
Ginger grows on a wide variety of soil. Stiff clays or course sands are not suitable for its cultivation. The soil of the virgin forest is rich enough for the growth of ginger for several years. The ideal soil for ginger is good garden soil, rich in humus, light and well worked, friable and family dry. Wet swampy ground does not suit it at all and soil apt to be water logged should be avoided.
The rhizome growth is better onslightly acidic soil rather than on nutral soil. The ginger is not tolerant to low pH. In another experiment, it was reported that no direct pH effects on ginger growth were evident over the pH range of 5.5 to 8.5 and was found to have a very low external Ca requirement.
Varieties
There are several cultivated types of ginger available in the country which are generally named after the localities viz: Malabar ginger, Cochin ginger, Assamese ginger, Himachal ginger etc. In varietal evaluation, different varieties from different places are evaluated on the basis of yield and quality components like dry ginger recovery, volatile oil and fibre contents in the rhizome etc. at different of India. The important recommended varieties which are grown in defferent parts of the country are given below :
Nadia: It is high yielding variety from Bengal and can be grown throughout ginger areas in India. Green ginger production is of about 49 tones per hectare, However, dry ginger recovery is about 22.40 per cent with crude fibre (8.13%).
Thingpui: It is a germplasm of Mizoram, extensively grown in the North Eastern Hill region of India and it has been introduced in other ginger growing areas also.
Thinglai: This is also germplasm of Mizoram, and its cultivation mainly confined into North Eastern Region of India.
Maran: It is a popular variety of Assam and is found to be least affected by Phytium aphanidermatum. The percentage of dry ginger (22.10) with crude fibre percentage is about 10.04.
Wynad Manentoddy: This is a popular variety of Kerala and is also known as Calicut ginger. It contains about 4.32 crude fibre with 17.81 per cent recovery of dry ginger.
Rio-de-Janerio: This is an exotic variety but well adapted to different ginger growing areas of India. It has about 5.19 per cent crude fibre with 16.25 per cent dry ginger recovery.
China: It is also an exotic high yielding variety and well adaptable in India conditions with 3.4% crude fibre and 15 per cent dry ginger.
The other cultivated varieties are Mysore, Eranad Manjeri, Vengara, Jorhat (Assam), Burdwan, Narasapatnam, Poona, Himachal, Siddipet, Australia, Kuruppampady, Valludvanod etc., which are localized in cultivation. Several other selections are being released from different research stations such as Suprabha, Surchi and Surabhi Salient features of these varieties are given below.
Suprabha: It is clonal selection from Kunduli Loal (PGS-35). Profuse tillering; plumpy fingers with oval tips; bright grey skin; fibre (4.4%); oil (1.9%). Oloresin (8.9%) both green and dry ginger; excellent for hill region; duration - 229 day and yield 3.40 t/ha.
Surabhi : this is clonal selection from X-ray Mutant of local cultivar (V1K1-3). High yielding (4.00t/ha); fiber (4%); oil (2.1%) fingers cylindrical; rhizomes dark glazy skin; profuse tillering and durations - 225 days.
The exotic varieties like Jamaica, Bangkok and China are less fibre content and good for vegetable ginger. Varieties Ernad Chernad, China, whereas varieties Sleevalocal, Narsapattam, Ernad Chernad and Himachal are rich in volatile oil content.
Planting Requirements
The mode of preparing the soil depends upon the condition of soil and climate. In the plains land is ploughed several times flowed by borrowings and planking to a fine tilth. It is then leveled and water channeled is made in order to irrigate the ground. In low land areas, where water is likely to stagnate, drains should be made to remove excess of water during the rainly seasons. In hilly areas, small beds are prepared in raised conditions and more hoeing or digging of soil should not be undertaken as it enhances soil erosion on steep slopes.
Ginger is universally propagated from the cutting of the rhizome i.e. known as bits. Bits are separated from the mother rhizome with a length of 3-5 cm, weighing 20-30 g and having at least one sound bud. Show Studies the effect of rhizome size 5 cm (20.1 g) 7 cm (30.2 g) and 9 cm (40.3 g) and the yield rose with rhizome size from 26.1 to 41.6 t/ha in pale yellow cultivar and from 26.7 to 32.6 t/ha in the red cultivar. Yield of fresh ginger (cv. Nadia) increased with planting piece weight (5-35 g) from 4178 to 26, 125 kg/ha. However, quality characters of ginger like oleoresin and oil percentage were not influenced significantly. The planting materials should be separated from the mother rhizome to allow it to wither and kept under moist condition to facilitate early and better germination. The percentage of germination and yield decreased when the number of days during storage was more than 21 days. The rhizomes detached from sprouted mother rhizomes gave yields of green ginger of 1.16 per cent plant. Large scale multiplication through culture has also been achieved in ginger.
Spacing trials were conduced in various ginger growing areas and is was conduced that a closer spacing of 20 and 35 cm between rows and 15 to 20 cm within rows are optimum. A seed rate (bits of rhizome) of about 15-20 q/ha is considered to be optimum for planting. Planting in the North Eastern region of India takes place during March-April. However, in other parts of the country planting takes place during June-July depending on the monsoon. In North India sowing of ginger is done with the onset of monsoon. Earlier planting by about the first week of April is found to increase the yield in rainfed crops. In small plots, bits are placed at prescribed distances at a depth of 4-5 cm and covered. On large scale plantations it is sown in furrows made by country ploughs at depth of 5-7 cm. Then the bits are covered with soil and leveled. In the hills of the north eastern region ginger is usually cultivated in raised beds or in the Jhum field. Traditionally the field is brought under fire as an integral part of jhumming, which helps in reducing the weed growth, soft rot disease and increases the availability of certain plant nutrients, particularly potassium.
Manuring
Ginger requires reasonable amounts of the manure and fertilizers. The yield rose 2995.73 kg/ha (control) to 8597.22 kg/ha on plots receiving 50 kg N. It declined to 4019 kg/ha on plots which received high N rate 120 (kg/ha). Nitrogen and potassium at rate of 90 kg/ha each in Orissa condition. The yield of ginger shoots and rhizomes at early and late harvests increased with the total amount of nitrogen applied upto the highest studied (336 kg/ha as (NH4)2 NO3). The (NH4)2NO3, urea and (NH4)2SO4 are equally effective as fertilizers but in terms of cost effectiveness the rating is urea ] (NH4)2NO3 ] (NH4)2SO4.
In addition to basal dressing of organic manure or farm yard manure 75 kg of N, 50 kg of P2O5, 50 kg, of k2O/ha should be applied. The whole of p2O5 and half of K2O are applied at the time of planting. Nitrogenous fertilizers are applied as a top dressing in two equal spilt doses, the first dose two months after planting in combination with the remaining quantity of K2O and the second dose a month later. In Maharashtra and some other parts caster or other cakes are top dressed in 2-3 spilt doses at a rate of 30-40 q/ha. In forest virgin soil, the growth is usually good without fertilizer application in the first year. Farm yard manure or compost when added at the rate of 10 tonnes/ha fulfils the manurial need of ginger.
Mulching
Mulching is not common in the hills, where ample moisture is available almost for two third of the growing season. In the plains mulching is an essential part of the ginger cultivation as it has a significant impact on yield by suppressing weed growth and preventing soil and moisture loss.
In a trial with the ginger cv. Maram, the plants were mulched with (a) banana leaves (b) grass or (c) soil. The best results with regard to yield, suppression of weeds and preventation of soil erosion were obtained with rhizome yield in a, b, c, and the controls were 31080, 23758, 17750 and 17960 kg/ha respectively. The mulching with dried leaves or straw showed remarkable suppression of early weed growth and increase in crop emergence, growth and yield. The yield without mulch was reduced by 42.8 per cent. Pre emergence application of 2, 4-D at 1 kg/ha or satrazine at 1 kg/ha was as effective as 4 hand weeding. 2-4D or satrazine with mulching gave the highest yield and net return. Nowadays mulching with green leaves is recommended in ginger at the rate of 15-20 tonnes per hectare. This will ensure better sprouting through maintenance of a more favourable regime and also helps in adding sufficient organic manure through its decomposition. It can be mulched twice in the growing season : first immediately after planting and the next about 45-50 days of planting. Green gram, cluster bean, glyricidia, sesbania etc. can be successfully used for mulching purpose.
In ginger growing areas weeding is done to avoid nurtrient loss by weeds. Earthing is given with two objectives to avoid the exposure of developing rhizome in heavy rainfall areas especially on hill slopes and to support the plants. Earthing alone with mulching reduces the weed growth and is also helpful for proper nourishment of a growing plant.
Irrigation
Ginger is generally grown as a rainfed crop in coastal belts as well as in hills. However, in low rainfall areas crops are wastered immediately after sowing if there is no rainfall for better germination. In the dry season from October to January, the ginger beds require irrigation at interval of 15-20 days for proper growth of plants and rhizomes, otherwise their growth stops and the aerial portion starts drying early. Light irrigation is done 5-6 days before harvesting for easy harvesting and to avoid breakage of rhizome.
Intercropping and Crop Rotation
Ginger may be grown alone or mixed with shade giving plants like banana, pigeon pea, caster and cluster bean. In jhum cultivation it is grown as a mixed crop with paddy and maize on hill slopes of the North Eastern region. Ginger intercropping with perennial crops such as citrus, coconuts, black-pepper and coffee can make the use of marginal land economic. At higher altitudes in Himachal Pradesh, tomato and chilli are grown as intercrops with ginger.
Crop rotation is essential for balancing the nutrient status of soil since ginger is an exhausting crop and also to avoid soft rot disease in ginger. In irrigated lands, ginger is rotated with planting turmeric, onion, garlic, chillies, other vegetables, maize and groundnut. Under rainfed condition, it may be grown once in 3-4 yearn in rotation with tapioca, sweet potato, yam, chilli and paddy.
Harvesting
Ginger can be harvested between 7-9 months after planting depending on the variety, agro climatic conditions and mode of use and local demand. The rhizome have maximum starch and lowest fibre content when harvest in the 7th or 8th month. The optimum time of lifting for early harvest to be at 24-26 weeks. Later harvest resulted in marked increase in fibre content. The yield of green ginger/plants is highest at 7 months, the oleoresin and volatile oil content were also highest. However, dry ginger recovery, is highest at 8 months. The maximum fresh and dry weight were obtained in cultivars Nadia and Maran, although essential oils and oleoresin content decreased with increasing maturity. The cultivars : Maran, Ernad Chernad, Karakkal and Nadia are recommended for dry ginger production.
The commercial harvest start from November onwards. The leaves at this time turn yellow and the pseudostem begins to dry. In irrigated crops 5-6 days before harvesting a light irrigation can be given to facilitate harvesting and also to avoid rhizome breakage during digging. Rhizomes are generally lifted with hand forks or tools.
Yield
The yield of ginger depends upon varieties agro climatic conditions, care and management of crop. The Nadia give highest yield of green ginger (4933.5 kg/ha) and dry ginger (1021 kg/ha). The yield of dry ginger is highest from Wynad region as compared to that of volatile oil from Kalimpong and oleoresin from the Nilgirs 220 q/ha in Thingpui and 229.5 q/ha in PGS-35 variety under Orissa condition. The highest yield with varieties Rio-de-Janerio and China (239 g/plant) in a varietal trial with twenty eight varieties. The recovery of dry ginger varies from 20-22 per cent.
Curing
Ginger is usually prepared for the market, as dried or cured ginger, preserved or green ginger. In India and the West Indies, the spice is prepared as dry ginger while in China it is prepared as preserved ginger.
Dried Ginger : After removing the dirt and roots from fresh harvested rhizome, it is soaked in hot water to facilitate the removal of the skin. The skin is scrapped off with pieces of sharpened bamboo. The scrapped produce is washed and dried in the sun for 3-4 days and hand rubbed to remove all the remaining bits of skin. Soaking the peeled rhizomes in a 2 per cent solution of lime water for 6 hours before drying gives the dry ginger a good appearance. During drying the rhizome looses nearly 70 per cent in weight. Ginger dried for the market contains 7 to 12 per cent moisture. It can be dried artificially by a heating evaporator but the rhizomes loose much of their aroma and become darker in colour with a burnt flavour. The sun drying is still the commercial way of drying. Sundrying also bleaches the produce. The essential oil which gives ginger its aromatic character is present in the epidermal cells and excessive or careless scrapping will result in damaging these cells leading to the loss of essential oils. Therefore, peeling should be done with great care and skill.
Grading
Grading of ginger is done on the basis of the size of dry ginger, dry matter and fibre content. The first grade is the very bold and round bits of dry ginger, with the maximum dry matter content and low fibre content. The second grade includes bits of bold, round to oblong, and is smaller than the first grade. The third and the fourth grades are smaller bits with a small amount of dry matter and high fibre content.
Storage
Seed ginger has to be stored for about 3 to 4 months from the time of harvesting to planting. Keeping the seed rhizomes in pits is found to be the best method of storage. For seed purposes well developed healthy rhizomes are selected at the time of harvesting and stored in pits under the shade or in cool place. The pits should be dug 1 meter deep and a layer of sand or saw dust is put at the bottom of the pit before storage. The pit is covered with a wooden plank leaving some space between the seeds and planks and is plastered with mud. A small hole is made in the plank through which a hollow bamboo is inserted to provide aeration for the rhizomes. Prestorage treatment with 0.025 per cent solution of ceresin wet or agroll added with quinolphos or methyle parthion for 30 minutes as prophylatic measure is recommended against soft-rot.
Ginger rhizomes harvested after 8-12 months were stored at 10-150C and 45-55 percent R.H. or 25-300 and 75 percent R.H. for 4 to 8 weeks. Oil and oleoresin yield increased with storage. The refrigerated storage upto 4 weeks did not affect quality but storage at room temperature had adverse effects.
Diseases and Pests
Ginger suffers from various diseases pests viz, rhizome-rot, bacterical wilt, leaf spot and pest viz, shoot borer, rhizome scale, leaf skipper and some storage pests also.
Rhizome Rot or Soft Rot: The disease is known to occur in almost all the ginger growing areas in India. It is caused by Pythium species. The affected plant tips turn yellow and the yellowing gradually spreads down the leaf, which ultimately wilt and dyes. In sever cases the basal portion of the plant becomes watery and soft tend the rhizome which is discoloured gradually decomposes, forming a watery mass enclosed by the touch rind. Such plants can be easily pulled out from the rhizome.
The incidence of Pythium zingubeum is reduced by pre treating the seeds with echelomezol (citridiazole) and by methyl bromide soil treatment. The spread of disease can be prevented with a soil drench of enchlomezol around the source of primary infection.
Bacterial Wilt: It is caused by Pseudomonas solanacearum. The wilt was first reported in Australia during 1965 and in India during. 1978 in the Wynad district of Kerala. The first noticeable symptom is downward curling of leaves due to loss of turgidity and within 3-4 days the leaves dry up. The affected rhizomes start rotting due to attack of saprophytic soil micro organisms. The rotted rhizomes amit foul smell and the affected plants die within two to three weeks.
However, preventive measures can avoid or minimize the disease incidence. Planting of disease free and healty rhizomes in clean land is essential. Soaking the seeds in (0.6%) mercury solution for 90 minutes is reported to minimize the disease incidence. Clean sanitation, long crop rotation and removal of infected plants should be strictly followed. Ojha etal obtained complete control of this disease caused by Pseudomonas solanacearum by rhizome treatment with enisan 6 + plantomycin for 30 minutes followed by 3 sprayings; the first after 30 days of planting and thereafter at 15 day intervals.
Leaf Spot (Phyllosticta Zingiberi): This is a fungal disease which appears on leaves in the from of minute colourless specks on the leaf lamina which soon grow into oval to elongated, irregular conspicuous spots with whitish centers and brown coloured margins with extended yellowish halos. These spots may cause extensive discolouration and drying of leaves. The disease resulted in heavy reduction in rhizome yield due to the destruction of chlorphyll and tissues. It can be controlled by one or two sprays of Bordeaux mixture 5:5:50. It can also be controlled by carbendazine and dithane M-45 and their persistency in the plant was 25 days and 15 days respectively.
Cercoseptoria zingiberis causing leaf spot of ginger is reported from Assam. Laptosphaeria gingiberi has also been reported to cause leaf spot and blight in Meghalaya. This disorder is also caused by Kuskia oryzae. Five fungicide treatments were compared. The yield in treatment benomyl (1g/L), mancozeb (2g/L) and ipodione at 2 ml/L were 34 and 35 per cent higher respectively than the control yield. Twelve treatments were given for each treatment, at 3 week intervals from 2 months after planting to one month before harvest. Leaf spot infection had no effect on nutrient uptake by the plants.
Shoot Borer (Dichorocis punctiferatis): It is a serious pest of ginger. The moth lays eggs on the growing bud, petiole or leaf. The colour of eggs is initially creamy white soon turns to pink. The young caterpillars bore through the central shoot of the plant and feed on the growing buds base resulting in withered and dried shoots referred to as 'dead heart' Later the caterpillar's advanced to rhizomes also.
Rhizome Scale (Aspidiella harlii): It congregates near the bud or growing tissues and sucks sap, debilitating, killing and finally drying up to rhizomes. Quinophos 0.1 per cent dip given to seed rhizomes for 5 minutes before planting could effectively control scale.
Leaf Skipper (Uadaspes folus): It is an olive green caterpillar with a disrict blach head which folds the leaves. The caterpillar feeds on the edge of the leaves and when one portion is completed, it moves on by making further folds and in the end the leaf is left with the rib only.
Storage Pests: The coffee bean weevil (Araecerus fascicutatus), drug store beetle (Stegabium peniceum), cigarette beetle (Lasioderma serricorne) and storage moths (Pyralis maniholatis) cause moths attack both fresh and dry ginger while the other two deteriorate dry ginger. The bean weevil attacks stored green buds and dries it. On dry material it multiplies rapidly and makes it a powder mass. The storage moths are of rare occurrence and live under the excreta covered webs and feed hiding inside. Drug store beetle and cigarette beetle occur in dry ginger. Fumigation with aluminium phosphide tablets at the rate of 3 to 4 tablets per tonne in an airtight store for 2-3 days is effective control.
Nematode (Meloidagyne incognita): Aldicarb at 2.0 kg a.i/ha followed by carbofuran at 2.0 kg a.i./ha effectively controlled M.incognita in ginger and improved plant growth in pot experiment. Soil amendment with poultry manure of sawdust plus urea are also found beneficial.
Description and Distribution
Ginger of commerce or 'Adrak' is the dried underground stem or rhizome of the Zingiberous herbaceous plant, Z. officinale, which constitutes one of the five most important major spices of India, standing third of fourth, competing with chillies, depending upon fluctuations in world market prices and world demand and supply position. During the past three years, 8,000-13,000 mt of dried ginger of different grades, worth Rs. 5-20 crores annually were exported to fifty countries. In fact, India still enjoys the unique position of being the largest producer and exporter of ginger in the world. India's production alone constitutes about 50% of the total world production of ginger. Besides, Indian ginger or Cochin ginger is also considered one of the best in the world.
Ginger, like cinnamon, clove and pepper, is one of the most important and oldest spices. It consists of the prepared and sundried rhizomes known in trade as 'hands' or 'races' which are either with the outer brownish cortical layers intact ('coated' or 'unscraped'), or with outer peel or coating partially or completely removed (i.e., 'uncoated' or 'scraped' or 'decorticated' ginger.) To improve their appearance, some grades or ginger are bleached by various means, e.g. by liming, etc.
According to available historical records, ginger was certainly known to and highly esteemed by the ancient Greeks and Romans who obtained this spice from Arabian traders via the Red Sea. It was introduced into Germany and France in the 9th century and to England in the 10th century. Since the ginger rhizome can be easily transported in a living state for considerable distances, the plant has been introduced to many tropical and sub-tropical countries. It is now cultivated in several parts of the world, the most important producing regions being India, Jamaica, Sierra Leone and Nigeria (West Africa), Southern China, Japan, Taiwan and Australia. Of these, Jamaica and India produce the best quality ginger, followed by the West African variety. Chinese ginger is usually not exported as a dried spice but preserved in sugar syrup or converted into 'ginger candy'. It has low pungency and aroma and hence it cannot be used for distillation or extraction purposes. Japanese ginger possesses a certain pungency, but lacks the characteristic ginger aroma. Ginger produced in other countries (Malaysia, Indonesia etc.) is not of much commercial importance yet.
In India, about 70% of the total ginger production is confined to Kerala state alone which also produces best quality ginger.
The major bottlenecks in boosting up further exports of ginger are (i) its higher fibre content than that of its main competitor, Jamaican Ginger, in world markets, and (ii) its higher cost of production. Both these problems can be overcome by developing higher yielding, disease-resistant, exotic varieties of lower fibre content but richer in volatile oil and oleoresin content. Nearly 26 varieties of ginger are under study at gricultural Research Station, Ambalavayal in Kerala, and elsewhere.
Ginger requires a warm and humid climate. It is cultivated from almost sea level to an altitude of 1500 m, either under heavy rainfall conditions of 150-300 cm or under irrigation. The crop can thrive well in sandy or clayey loam or lateritic loam soils.
Volatile Oil
On steam distillation, dried, cracked and comminuted ginger yields 1.0 to 3.0% (av. 2.0%) of pale yellow, viscid oil. The oil possesses thearomatic odour but not the pungent flavour ('bite') of the spice of course, the odour of the oil is quite lasting.
The physico-chemical characteristics of the oil vary depending upon the variety, age or period of storage and method of extraction, etc. They range as follows-Sp.gr. at 15°C:0.876-0.887; Opt. Rot.:-30° to -44°20', occasionally as low as - 23°58;. Ref. index at 20°C: 1,4876 to 1,4917; Acid no : 1.1-3.7; Sap. no : 0.9-11.2 (upto 20.6).
It is more economical and convenient to recover oil or oleoresin from dried ginger than from fresh ginger. However, fresh scrapings of ginger are quite rich in oil and should be immediately used for steam distillation, otherwise, 60-80% of the volatile oil is lost overnight, as experienced by the author in his detailed studies on the development of useful products from ginger, including volatile oil, oleoresin and edible products from the exhausted or 'spent' ginger.
Use of Ginger Oil
As Flavourant: Ginger oil is primarily used as a food flavourant in soft drinks like ginger ale, bitters, cordials and liquors, as a spice in bakery products, confectionery, pickles, sauces and preserves, etc.
Pharmaceutical Uses: The pharmaceutical use are carminative, rubefacient, stimulant, in alcoholic gastritis, dyspepsia, flatulent colic, etc. Veterinary used of ginger are as stimulant and carminative, in indigestion of horses, and cattle, in spasmodic colic of horses, and to prevent the griping by purgatives.
Use in Perfumery: The oil of ginger finds limited use in perfumery, where is imparts a unique individual note to compositions of the oriental type.
Asafoetida
Description and Distribution
Asafoetid or Asafoetida is the dried latex or oleogum oleoresin exuded from the living rhizome or rootstock or taproot of several species of Ferula, three of which grow in India, mainly in Kashmir. These are the perennial herbs belonging to the genus Ferula which are the sources of the oleogum resins used as condiment as well as in medicine. The spices are distributed from the Mediterranean retion to Cental Asia. The more important ferula oleogum resins imported into India, chiefly from Iran and Afghanistan, are (a) asafetida, (b) galbanum and (c) sumbal. Of these, asafoetida is the most important. A part of the imported resin is re-exported from India to various countries. The trade name asafetida is based on the scientific name of a related species, 'Ferula asafoetida'. Nearly a crore of rupees worth of asafoetida is bveing imported annually into India. The gross value of the sales, especially of the compounded asafoetida, mostly as consumed in South India, is probably many times more.
Surprisingly enough very few of the consumers are aware of what substane it is, to what extent it is pure an whether it could be produced in India to the extent of our becoming at least self-sufficient.
Extraction of Asafoetida
The Ferula plants from which the asafoetida of commerce is extracted, have massive taproots or carrot-shaped roots, 12.5 to 15 cm in diameter at the crown when they are 4-5 years old. In March-April, Just before the plants flower, the upper part of the living rhizome/root is laid bare and the stem cut off close to the crown. The exposed surface is covered by a dome-shaped structure made of twigs and earth. A milky juice exudes from the cut surface. After some days, the exudates is scraped off and a fresh slice of the root cut when more latex exues; sometimes the resin is removed along with the slice. The collection of the resin and the slicing of the root are repeated until exudation ceases (about 3 months after the first cut). The resin is sometimes collected from successive incisions made at the junction of the stem of rhizome and the taproots. With three incisions, some plants have been reported to yield about 1 kg or more of gum-resin.
Asafoetida is acrid and bitter in taste and emits a strong, disagreeable, pungent, allianceous odour due to the presence of sulphur compounds therein. Hence its common name abroad, 'Devils dung'.
Types/Varieties of Asafoetida
Asafoetida of commerce is available in three forms, viz. 'tears', 'mass' and 'paste'. The tears, constituting the purest form of the resin, are rounded or flattened, 5-30 mm in diameter and grayish or dull yellow in colour. The two types are recognized according to whether the tears retain the original pale colour for years or gradually become dark or reddish-brown. Mass asafoetida is the common commercial form. It consists of tears agglutinated into a more or less uniform mass usually mixed with fragments of root, earth, etc. The paste form also contains extraneous matter.
There are several varieties of asafoetida which come under different classification and are priced accordingly. There are tow major varieties of asafoetida, namely 'Hing' and 'Hingra'. Hingra is said to be inferior to hing which is richer in odour and is the most fancied. Hing is further classified as 'Irani Hing' and 'Pathani Hing', according to their country of origin, the former being from iran, and the latter from Afghanistan. Amon them, again there are several varieties. Of these 'Hadda' is the most priced and the strongest. The two varieties of Irani asafoetida are 'sweet' and 'bitter' asafoetida. Sweet asafoetida is obtained from the horizontal cutting of the stem. Its colour is brown, transparent. Bitter asafoetida is obtained from the cutting of the plant root. No pieces of wood exist. It is similar to amber-coloured separated grains or a dough or white and red colour.
The two broadly recognized classes of asafoetida sold in the market with which most of the consumers may be familiar, are the white or pale variety and the dark or black variety. The former is water soluble and the latter is oil soluble. The question often asked is: What is the real difference between these two varieties? If one gets to know the chemical composition of asafoetida there is not much difference. After all, asafoetida is an oleogum-resin; where the gum portion preponderates, as in High, it is water soluble, and where the resin portion preponderates, as in Hingra, it is oil soluble. Thus, depending upon the extent to which one component or the other preponderates, a sample of asafoetida is water-soluble or oil-soluble. The components to which asafoetida owes its characteristic odour, reside in the oil portion and are believed to be due to two classes of compounds. One of them is ferulic ester and the other-the more important one-is a volatile oil consisting of different sulphur compounds, some of which are similar to those found in garlic and onion. Briefly, Hingra is the exudates of Ferula foetida Regal (Syn F. scorodosma), while hing is the exudates of F. asafoetida (Syn: F. alliancea Biss). Irani Hing samples mostly contain woody residue but Pathani ones are comparatively free from wood. Speciement with a wet surface and agglutinated appearance occur in Pathani, but none in Irani. Hingra is heterogenous in colour, and consistency, etc.
Composition
| Asafoetida contain- |
|
| Resin |
40-64% |
| Gum about |
25% |
| Volatile Oil |
10-17% |
| Ash |
1.5-10% |
The resin portion consists chiefly of asaresinotennol, free or combined with ferulic acid. Umbelliferone seems to be present in the combined state.
According to the latest amendment of Food Adulteration Act, 1954, amended up to date, the definition for Hing or Hingra and Bandhani Hing is as under.
Asafoetida (Hing or Hingra) means the oleogum resin obtained from the rhizome and roots of ferula alliances, Ferula rubricaulis and other spices of Ferula. It should not contain any colophony resin, galbonum resin, ammoniaccum resin or any other foreign resin.
Bandhani Hing or compounded asafoetida is composed of one or more varieties of asafoetida (Iran or Pathani Hing or both) and gum arabic, edible starches or edible cereal flour. It should not contain colophony resin, galbonum resin, ammoniaccum resin or any other foreign resin, coal-tar dyes, and mineral pigment.
Oil of Asafoetida
The oil of asafoetida is obtained by steam distillation of the gum-resin. Yield varies from 3 to 20%. The physico-chemical properties of the Bombay asafoetida are as follows-Sp.gr. at 20°C, 0.906-0.973; (a) Opt. rot. at 20°C, 9° 0' 9.18; Ref. ind. at 20°C, 1.493-1.518; and sulphur content, 15.3-29.0%. The chief constituent of the oil is secondary butylpropenyl disulphide, pinene, another terpene, and an unidentifides, a trisulphide, pinene, another terpene, and an unidentified compound. The disagreeable odour of the oil is reported to be due mainly to the disulphide (C11H20S2). The oil has not attained any commercial importance. The flavouring and pharmaceutical industries employ chiefly alcoholic tinctures of the gum-resin.
Adulteration
Commercial asafoetida is grossly adulterated with gum Arabic, other gum-resins, rosin gypsum, red clay, calk, barley, or wheat flour, slices of potatoes, etc. different grades of asafoetida (Hingra, Hadda Hing, Hira Hing) varying in price are sold in the bazaar.
Uses
As Flavourant: Asafoetida is extensively used in India for flavouring curries, sauces and pickles in conjunction with onion and garlic. In Iran (Persia), the natives rub asafoetida on warmed plates prior to placing meat on them. Besides, the large cabbage like tops of the plants are relished raw by the natives.
In Medicine: Medicinally, it stimulates the intestinal and respiratory tracts and the nervous system. It is useful in asthma, for intestinal flatulence. It is also administered in hysterical and epileptic affections and in cholera. Asafoetida is often employed in veterinary medicine. It is a very useful remedy for relieving spasms and in indigestion and clic. It is applied externally on the stomach to stimulate the intestines.
In the Ayurvedic system of medicine, the well-known recipe called Hingashtaka contains asafoetida as one of the important ingredients.
However, the important question still remains as to whether such a reputation which asafoetida enjoys as a medicine is scientifically well-founded. If so, the precise mode of its action is yet to be understood clearly. Likewise, there is also need for rigorous implementation of purity standards as well as the development of rapid and reliable analytical methods for the detection of adulteration. According to the Prevention of Food Adulteration Act (PFA), asafoetida (Hing or hingra) shall not contain any colophony resin, galbonum resin, ammoniacum resin or any other resin, but it is generally felt that these standards do not fully reflect the true quality of asafoetida.
Vanilla
Bot. Name : Vanilla Fragrans (Salisbury) Ames.
Description and Distribution
Vanilla is a tropical orchid cultivated for its delicate pleasant flavour, usually added to sweet dishes, etc.
The vanilla pods or sticks of commerce are the cured fruits or beans of the climbing orchid V.fragrans or V.planifolia. It is a native of the Atlantic coast from Maxico to Brazil. Vanilla cultivation spread to other countries after the discovery of America. The important vanilla producing countries are: Madagascar, Mexico, Tahiti, Comoros, Reunion, Indonesia, etc. The world production of cured vanilla is abut 1,630 mt and the exports from theaboce countries figure around 1,500 mt valued at US $ 16 million. Now, the Malagasy Republic alone grows about 80% of the world crop of vanilla beans.
Though vanilla was introduced in India as early as in 1835, to much headway has been made so far in extending the area under this crop, despite the universal popularity of its use in numerous sweet dishes like puddings, chocolate, confectionery cakes, beverages and ice-creams etc. within the country. Vanilla worth Rs. 1.2 to 4 lakhs is being imported into India annually, in addition to the import of huge quantities of synthetic vanillin and vanilla essence as follows:
| Vanilla & Vanilla products |
Quantity (kg) |
Value (Rs. Lakhs) |
| Vanilla |
1,200 |
1.20 |
| Vanillin |
24,616 |
11.25 |
| Ethyl Vanillin |
6,904 |
5.11 |
| Iso-Eugenol (used partly for the Manufacrure of Vanillin) |
5,018 |
3.25 |
This is in addition to the synthetic vanillin being produced in the country itself. It is a matter of serious concern that valuable foreign exchange worth about Rs. 21 lakhs is being drained from the country. Concerted efforts should be made to extend the area under this valuable crop unsuitable localities by training the prospective farmers in various aspects of vanilla farming, such as hand pollination versus. Hormone spray, curing and processing of vanilla beans their packaging and storage based on the useful researches being conducted at the Central Horticultural Research Station, Ambalavayal and elsewhere. India has ideal agro-climatic conditions for the cultivation of vanilla, but at present, it is grown in only about 20 hectares (Anon. 1993 a) in Wyanad (Kerala) and the Nilgiris (Tamil Nadu). Thus, there is ample scope for extending the area, notably in Kerala, and at least in home-gardens, especially in arecanut and coconut gardens where irrigation facilities are available. The major bottleneck of hand pollination may be overcome through hormone sprays.
Vanilla is generally propagated by cutting of 90-100 cm length for better and faster growth and early flowering. Tissue culture plants of vanilla can also be used for planting instead of using cuttings.
The ISO (International Organization for Standardization) have included the following two species of vanilla in the list of spices in addition to V. fragrans mentioned above.
- Vanilla Pompona Schneider
- Vanilla tahitensis Moore.
Harvesting and Curing
Different methods of curing vanilla after harvest are being followed in different countries. Of the various processes tried at Ambalavayal Farm, curing vanilla by the Medican Process has been found to be the best under Wyanad conditions, both for the attractive appearance and high aroma or vanillin content (2.3-29%). During curing (fermentation) process, vanilla pods get the flavour as result of naturally induced enzymatic action of b-glucosidase on the precursor glucovanillin with the formation of vanillin and sugar. Vanillin aroma is the dominant flavour characteristic of vanilla.
Climatic conditions, timing of the harvest and the extent of sweating of the pods during curing, are some of the important facrors that determine the vanillin content and quality of the pods. About ½ kg of cured beans can be obtained from 3.5 to 4 kg of green vanilla beans.
Quality Attributes of Vanilla
The most import quality attributed of cured vanilla beans for grading purposes are : length of beans, aroma, colour, flexibility luster, and freedom from blemishes, mildew and insect infestation. The best quality pods are 17-25 cm long, highly aromatic, free from mildew, blemishes and insect infestation, dark brown in colour, fleshy, supple and some what oily in appearance. It may be cautioned here that the quality of vanilla beans should not be judged only by their vanillin content. The well cured beans thus graded and packed in air-tight tin containers can keep well for a long time.
Composition
The proximate composition of whole vanilla beans is as under:-
| Moisture: |
25.85-30.93% |
| Protein: |
2.56-4.87% |
| Fatty Oil: |
4.68-6.74% |
| Volatile Oil: |
0.0 to 0.4% |
| Nitrogen free extract: |
30.35-32.90% |
| Carbohydrates: |
7.1-9.1% |
| Fibre: |
15.27-19.6% |
| Ash |
4.5-4.7% |
| Calcium: |
19.7% |
| Potassium: |
16.2% |
| Sodium: |
6.7% |
| Phosphorus: |
9.5% |
| Iron: |
0.35% |
| Nanillin: |
1.48-2.90% |
| Rasins: |
1.5-2.6% |
Adulteration/Substitution
Vanilla beans contain methyl vanillin but ethyl vanillin is synthetic and more aromatic than methyl vanillin. The choice between methyl and ethyl vanillin depends of the preparation and the end use. Ethavan and Vanaldol are the trade names of ethyl vanillin.
Synthetic vanillin can be used in the place of true vanilla for cheap flavouring such as vanillin solution and vanillin sugar. Caoumarin, a compound with a vanilla-like flavour can be used as a cheap substitute vanilla. However, since it has recently proved to be toxic, its use for flavouring foods shold be banned.
The appearance and odour of the spent (solvent treated) vanilla beans is reported to be improved by treating them with benzoic acid. In the event of suspicion, a simple test can be conduced by heating the crystals over a flame which will emit irritating odour due to the presence of benzoic acid.
Vanilla Extract/Essences
Vanilla extracts are in great demand in America as are cured vanilla beans in European countries. The vanilla flavour can be extracted with alcohol. The colour of the extract depends on the strength of the alcohol, used, duration of extraction and the presence of glycerin. Dark coloured extract is obtained from dry beans and the presence of glycerin deepens the colour of the extract. Vanilla extract is stored in stainless steel or, aluminium or glass containers. Ageing for 25-30 days improves the aroma, due to formation of esters from acids in the presence of 42-45% alcohol. Wooden containers should be avoided completely as they adversely affect its flavour because of the alcoholic extractions from the wood itself.
However, it may be added that the cost of natural vanilla extract is about 20 times that of the synthetic vanilla flavouring of course, these imitation flavour are inferior to the natural ones.
Vanilla Sugar
The vanilla extract is mixed with sugar and made into a powder called 'powdered vanilla' or vanilla sugar.
Uses
As Food Flavourant & in Perfumery
Vanilla, today, constitutes the world's most popular flavouring for numerous sweetened foods. 'Vanilla Sugar' is used in the manufacture of chocolates. Vanilla flavouring is used in countless commercial food products, in liquor, in cheap brandy and in whisky. In the USA, most of the vanilla flavour is marketed in the form of pure vanilla extracts, widely used as flvouring par excellence for ice-creams, soft drinks, chocolate, confectionery, candy, tobacco, baked foods, puddings, cakes, cookies, liquors and as a fragrantly tenacious ingredient of perfumery.
In Medicine: The medicinal used of vanilla have gradually reduced. It is no longer regarded as a drug. However, it is still the most lovable flavourant.
Vanillin: Thill recently, the bulk of the vanillin produced was used as a flavouring agent in different foods. The remaining quantity was used in deodorants, perfumes, odour fixatives, and as a masking agent in pharmaceutical and vitamin preparations.
After 1970, the greater use for the technical grade vanillin (98% pure, less desirable for food flavouring) is as a chemical intermediate in the production (synthesis) of a number of pharmaceutical products. Foaming in lubricating oils can be prevented by the use of vanillin. Vanillin can be used as a brightener in zinc planting baths. It can also be used as an aid for the oxidation of linseed oil and as soluilising agent for the riboflavin (vitamin B2) as vanillin is an antioxidant.
