In this article we will discuss about:- 1. Origin of Areca Nut 2. Modern Day Consumption of Areca Nut 3. Cultivation 4. Effects of Areca Nut on Health 5. Curing 6. Components 7. Uses.
Origin of Areca Nut:
The areca nut is not a true nut but rather a drupe. It is commercially available in dried, cured and fresh forms. While fresh, the husk is green and the nut inside is so soft that it can easily be cut with an average knife. In the ripe fruit the husk becomes yellow or orange and, as it dries, the fruit inside hardens to a wood-like consistency. At that stage the areca nut can only be sliced using a special scissor-like cutter.
Usually a few slices of the nut are wrapped in a Betel leaf along with lime and may include clove, cardamom, catechu (kattha), etc. for extra flavouring. Betel leaf has a fresh, peppery taste, but it can be bitter depending on the variety. This is called tamboolam in Sanskrit.
Areca nuts are chewed with betel leaf for their effects as a mild stimulant, causing a mild hot sensation in the body and slightly heightened alertness, although the effects vary from person to person. The effect of chewing betel nut is relatively mild and could be compared to drinking a cup of coffee.
The areca nut contains tannin, Gallic acid, a fixed oil gum, a little terpineol, lignin, various saline substances and three main alkaloids – Arecoline, Arecain and Guracine which have vasoconstriction properties. The betel leaf chewed along with it contains eugenol, also a vasoconstrictor. Many chewers also add small pieces of tobacco leaf to the mixture, thereby adding the effect of the nicotine, which causes greater addiction than the drugs contained in the nut and the betel.
In China, East and North-East India areca nuts are not only chewed along with betel leaf but are also used in the preparation of Ayurvedic and Traditional Chinese medicines. Powdered areca nut is used as a constituent in some tooth powders. Other medicinal uses include the removal of tapeworms and other intestinal parasites by swallowing a few teaspoons of powdered areca nut, drunk as a decoction, or by taking tablets containing the extracted alkaloids.
The Term “Betel Nut” and the Colonial Legacy:
In English, the areca nut is also widely known as Betel nut (or “Betel-nut”), because it is mostly chewed along with Betel, the leaf of a vine belonging to the Piperaceae family. The term “Betel nut” is technically incorrect, for the betel vine produces no nuts, and this inaccurate term creates quite a bit of confusion regarding the discernment between the nut and the leaf. Generally, “paan” is used to refer to the betel leaf. However, the common use of the word “paan” refers mostly to the chewing mixture, including areca nut, wrapped in the leaves.
The muddling between the areca nut and the betel leaf, by calling the nut “betel nut”, is restricted to the languages of the colonizing powers, like English, French, Dutch, Portuguese and German. This lack of accuracy is likely a legacy of the colonial era in which chewing the mixture was restricted to “the natives”.
In the languages of the places where the Areca nut is traditionally chewed there is a clear and separate term for the areca nut and another for the betel leaf. This clear distinction is important in societies where both the areca nut and the betel leaf have a ceremonial and even sacred value. Furthermore, there is commonly a specific verb for the activity of chewing both of them together.
There was a certain amount of prejudice among the European colonial powers against the tradition of chewing of Areca nut and betel. Unlike the quick adoption of tobacco by Europeans in the American colonies, chewing areca nut and betel was an addictive habit not adopted by the colonizers of South and Southeast Asia. Officers freshly posted in the East India or Indochina colonies, whether British, French or Dutch, regarded the red-stained mouths of pan-chewers with dread, as something too foreign and weird for them.
This abhorrence is not only evident in the writings of authors of the Victorian era, but in more recent writers like George Orwell, Somerset Maugham and V.S. Naipaul. Often this spirit expresses itself in mockery and ridicule, like in the Broadway musical tune “Bloody Mary” (from Rodgers and Hammerstein’s South Pacific) with the line “Bloody Mary’s chewing betel nuts… and she don’t use Pepsodent.”
Chewing the mixture of areca nut and betel leaf is a tradition, custom or ritual which dates back thousands of years from South Asia to the Pacific. It constitutes an important and popular cultural activity in many Asian and Oceanic countries, including Taiwan, Myanmar, Cambodia, the Solomon Islands, Thailand, Laos, and Vietnam.
It is not known how and when the areca nut and the betel leaf were combined together into one psychoactive drug. Archaeological evidence from Thailand, Indonesia and the Philippines suggests that they have been used in tandem for four thousand years or more.
In Vietnam the areca nut and the betel leaf are such important symbols of love and marriage that in Vietnamese the phrase “matters of betel and areca” is synonymous with marriage. Areca nut chewing starts the talk between the groom’s parents and the bride’s parents about the young couple’s marriage.
Therefore the leaves and juices are used ceremonially in Vietnamese weddings. The folk tale explaining the origin of this Vietnamese tradition is a good illustration of the fact that the combination of areca nut and the betel leaf is ideal to the point that they are practically inseparable, like an idealized married couple.
Malay culture and tradition hold betel nut and leaves in high esteem. Traditionally, a guest who visits a malay house are given a tray of betel nuts and betel leaves, the same way as one offering drinks to a guests now. There’s even a malay proverb about the betel nut, “bagaikan pinang dibelah dua”, loosely translated, like a betel nut divided in half. It usually refers to newlyweds, who are compatible to each other, just like a betel nut when divided in half. The Proverb is closely analogous to the contemporary “two peas in a pod”.
In the Indian Subcontinent the chewing of betel and areca nut dates back to the pre-Vedic period Harappan Empire. Formerly in India and Sri Lanka it was a custom of the royalty to chew Areca nut and betel leaf. Kings had special attendants carrying a box with the ingredients for a good chewing session. There was also a custom to chew Areca nut and betel leaf among lovers because of its breath-freshening and relaxant properties.
Hence there was a sexual symbolism attached to the chewing of the nut and the leaf. The areca nut represented the male and the betel leaf the female principle. Considered an auspicious ingredient in Hinduism, the Areca nut is still used along with betel leaf in religious ceremonies and also while honoring individuals in most of Southern Asia.
In Assam it is a tradition to offer Pan-tamul (Betel leaves and raw areca nut) to guests after tea or meals in a brass plate with stands called a Bota. Among the Assamese the areca nut also has a variety of uses during religious and marriage ceremonies, where it has the role of a fertility symbol.
A tradition from Upper Assam is to invite guests to wedding receptions by offering a few areca nuts with betel leaves. During Bihu, the husori players are offered areca nuts and betel leaves by each household while their blessings are solicited.
Spanish mariner Alvaro de Mendana reported how the Solomon Islanders were chewing the gut and the leaf with caustic lime that stained their mouths red. He noticed that friendly and genial chief Malope in Santa Isabel Island was offering him the stuff as a token of friendship every time they met. The adding of tobacco leaf to the chewing mixture is a relatively recent introduction, for tobacco was introduced from the American continent in colonial times.
Modern Day Consumption of Areca Nut:
In India (the largest consumer of areca nut) and Pakistan the Id in ready-to-chew pouches called “Pan Masala” or supari, as a mixture of many flavors whose primary base is areca nut crushed into small pieces. Pan Masala with a small quantity of tobacco is called gutka. The easily-discarded small plastic supari or gutka pouches are an ubiquitous pollutant of the South Asian environment. Some of the liquid in the mouth is usually disposed of by spitting, producing bright red spots.
The Shimoga District in Karnataka is presently the largest producer of betel nut in India. In the Maldives areca nut chewing is very popular, but spitting is frowned upon and regarded as an unrefined, gross way of chewing. Usually people prefer to chew thin slices of the dry nut, which is sometimes roasted.
“Kili”, a mixture of areca nut, betel, cloves, cardamom and sugar is sold in small home-made paper pouches. Old people who have lost their teeth keep “chewing” by pounding the mixture of areca nut and betel with a small mortar and pestle.
In Papua New Guinea and the Solomon Islands, fresh areca nut, betel leaf or ‘fruit leaf’ (“daka” in PNG) and lime are sold on street corners. In these countries, dried or flavoured areca nut is not popular. Areca nut chewing has recently been introduced into Vanuatu where it is growing in popularity, especially in the northern islands of the country. In Guam, betel and areca nut chewing is a social pastime as a means to extend friendship, and can be found in many, if not most, large gatherings as part of the food display.
“Betel nut beauty” on the road between Taipei and Hsinchu:
In Taiwan, bags of 20 to 40 areca nuts are purchased fresh daily by a large number of consumers. To meet the steady year-round demand, there exist two kinds of betel-nut shops, each of which sells cigarettes and drinks including beer in addition to their primary purpose of supplying betel and nuts. On one hand, there are small mom and pop shops that are often poorly maintained and often do not stand out from other stores nearby.
On the other hand, the second provides a sight unique to Taiwan. Such a shop often consists of nothing more than a single free-standing room, or booth, elevated one meter above the street that measures less than 3 meters by 2 meters. Large picture windows comprise two or more of the walls, allowing those who pass by a complete view of the interior. The interior is often painted brightly.
Within such a shop, a sexily dressed young woman can be seen preparing betel and areca nuts. Shops are often identified by multicolored (commonly green) fluorescent tubes or neon lights that frame the windows or that are arranged radially above a store. Customers stop on the side of the road and wait for the girls to bring their betel and areca nut to their vehicles.
In Thailand the consumption of areca nut has declined gradually in the last decades. The younger generation rarely chews the substance, especially in the cities. Most of the present-day consumption is confined to older generations that is mostly people above fifty. Even So, small trays of betel leaves and sliced tender areca nut are sold in markets and used as offerings in Buddhist shrines.
In the Philippines, chewing the areca nut and betel leaf was a very important tradition in the past. Nowadays this tradition is almost dead among the urban people in the cities and big towns who consider that it is against the general trend of being westernized. Except in some small towns, chewing betel has largely been replaced by chewing gum and cigarettes.
In the United States, areca nut is not a controlled or specially taxed substance and may be found in some Asian grocery stores. However, importation of areca nut in a form other than whole or carved kernels of nuts can be stopped at the discretion of US Customs officers on the grounds of food, agricultural, or medicinal drug violations.
Such actions by Customs are very rare. In the United Kingdom areca nut is readily available in Asian grocery stores and even in shredded forms from the World Food aisles of larger Tesco supermarkets.
Cultivation of Arecanut:
Arecanut palm (Areca catechu L.) is cultivated for its kernel, which is chewed in its tender, ripe or processed form. The north-eastern region of India is a major producer of arecanut in India, producing 21% of the total national production. Most of the production is exported to outside the region.
The major processing clusters are in northeast India with large (5-7 tonnes of processed arecanut produced weekly) and medium sized (2-3 tonne of processed arecanut produced weekly) units located in Rupahi and Howly, in the state of Assam. Apart from these clusters, thousands of cottage-level processing units are also found in Cachar, Karimganj, Darrang, Dhubri and Kokrajhar districts of Assam.
There are two varieties of processed arecanut processed in the state of Assam and other states in India-Boiled, dried nuts (red in colour, called chikni) and non-boiled, sun dried nuts (called supari). Tender green arecanut are dehusked, boiled and dried to obtain the chikni. Boiling is done in batches in flat, open, iron pans (4-5 feet diameter) where chopped nut pieces are mixed with colour and boiled at 70- 80°C, to cook and absorb the colour.
The first batch of boiling in a day takes 50 minutes and subsequent batches take 30 minutes. Though the nuts should be boiled for 20 minutes to get restrict the boiling time to save the scarce fuel wood. The drying (slow heating) is done in brick-cement/brick-mud frame sheds (7 feet height and 7.5 feet width) with vertical partitions.
Thick bamboo mats are used to spread the chopped nuts out for drying and wood is fired in each partition on the ground, well below the bamboo mats. In the large and medium sized units, fire curing is initially done for 12 hours at a temperature of 70-75°C and then the dried product is further sun dried for 2-3 days to remove any residual moisture.
On average 100 to 150 kg fuel wood arecanut, of which 60% is used for boiling and the rest for drying. The average wood-burning rate for boiling is 115 kg per hour, with SFC (specific fuel consumption) of 0.70 kg wood per kg boiled nut. Detailed water boiling tests carried out on the vessel-bhatti combination currently used, revealed that the useful power requirement is 30-35 kWth. TERI has successfully developed an integrated gasifier-based system for boiling, as well as drying, and has successfully demonstrated the application in the Rupahi cluster.
The gasifier with a wood consumption rate of about 20 kg/hr capacity, was used for boiling arecanut in the existing boiling pan and also utilized the hot flue gases for drying. The gasifier could also be operated successfully using waste arecanut husk (a byproduct during de-husking operation) that makes the gasifier option even more attractive Area under areca nut and production of arecanut in the country have increased considerably in 11 years till 2004-05, according to a database on arecanut and spices published by the Directorate of Arecanut and Spices Development, Kozhikode, under the Union Ministry of Agriculture, in 2007.
In response, sources in Mangalore Agriculturists’ Sahakari Sangha (MASS) and Central Arecanut and Cocoa Marketing and Processing Cooperative Limited (CAMPCO) told The Hindu that this is not a healthy trend in the interest of arecanut growers, especially in traditional areas, as it will affect the market.
As per the database, imports of arecanut had also gone up in the last five years from 14,788 tonnes in 2001-02 to 53,275 tonnes in 2005-06. This meant that crises in the domestic market would also increase, they said.
The database said that the statistics from 1994-95 to 2004-05 were sourced from the Directorate of Economics and Statistics, Delhi. Area under arecanut went up from 2.43 lakh hectares in 1994-95 to 3.74 lakh hectares in 2004-05. Production went up from 2.89 lakh tonnes to 4.56 lakh tonnes, respectively, it said.
Effects of Areca Nut on Health:
The International Agency for Research on Cancer (IARC) regards the chewing of betel and areca nut to be a known human carcinogen Certain studies have sought to prove that regular chewers of betel leaf and areca nut have a higher risk of damaging their gums and acquiring cancer of the mouth, pharynx, oesophagus and stomach. Studies have found tobacco and caustic lime increase the risk of cancer from betel nut preparations.
Studies exist of the use of a “pure” paan preparation- areca nut, betel leaf, and lime. A single recent study claimed that unprocessed areca nuts, at high doses, displayed a very weak carcinogenicity. In contrast, since 1971 many studies have found betel nut extracts to cause cancer in rodents.
In 2003 the International Agency for Research on Cancer (IARC) reached the conclusion that there is sufficient evidence that the habit of chewing betel quid with or without tobacco is carcinogenic to humans Support is provided by a recent study which found that paan without tobacco is a risk factor for oral cancer. They found paan with and without tobacco increased oral cancer risk by 9.9 and 8.4 times respectively. The paan and extract studies suggest betel nut alone is extremely carcinogenic.
Chewing Betel Nut alone has been Linked to Oral Submucous Fibrosis:
According to Medline Plus, Long-term use has been associated with oral submucous fibrosis (OSF), pre-cancerous oral lesions and squamous cell carcinoma. Acute effects of betel chewing include asthma exacerbation, hypertension, and tachycardia.
There may be a higher risk of cancers of the liver, mouth, esophagus, stomach, prostate, cervix, and lung with regular betel use. Other effects can include a possible effect on blood sugar levels, possibly increasing the risk of type two diabetes.
Regular betel chewing causes the teeth and gums to be stained orange/red, a color that was formerly considered attractive in certain cultures. In Telugu poetry the slightly red-stained lips of a young woman chewing areca nut and betel are considered a mark of beauty.
It is believed that regular chewing reduces the incidence of cavities, and toothpastes were once produced containing betel extracts. However, the increase in mouth ulcers and gum deterioration caused by areca nut and betel chewing may outweigh any positive effects.
According to traditional Ayurvedic medicine chewing areca nut and betel leaf is a good remedy against bad breath (halitosis). Medline-Plus indicates “poor-quality research” showing a possible beneficial effect for sufferers of anaemia during pregnancy. However, it counsels against areca nut chewing due to a possible risk of spontaneous abortions.
It also indicates “poor-quality studies” showing a possible beneficial effect on schizophrenia and for stroke recovery. Some people claim that chewing Areca nuts with betel increases the capacity to work.
Sanskrit – Puga or Pugaphala, Bengali – Shupari, Hindi, Marathi – Supari
Areca Nut Curing:
Areca nut (Areca catechu) is popularly known in India as Supari and Shrivardhani. In Meghalaya it is named as Kwai. It thrives in the area owing to heavy rainfall and good drainage. The areca nut is a shade loving plant. The climatic conditions of Meghalaya suit the trees due to the high rainfall (3000 mm). Steep slopes allow continual drainage and clouds provide enough shade for the luxuriant growth of the plant.
There is around 6200 hectare area under nut cultivation, which yield around 4200 to 5900 tonnes of the produce every year in the state. Areca nut is considered to be a native of Malaya. This is extensively grown in North Eastern part as well as peninsular Indian region. The palm is tall and slender with a smooth whitish stem reaching a height of 12 to 18m. The stem surmounted by a crown of pinnate leaves. 1-2 m long among which the pinnate is confluent.
The fruit is ovoid which is approximately 2.25 cm across and 3.79-6.00 cm long. The fully ripe fruits look bright orange. The pericarp (60%) is hard and fibrous and the kernel (seed 40%) is called areca nut. The nut is about 2.25-3.25 cm in diameter, 2.00-3.00 cm long, varying in shape from conical to spherical and brown in colour with the white tints.
Method of Consumption and Curing in NE Region:
The fruit (nut) is consumed in different manners. The crudest way is to get the ripe fresh fruit, shell it with a knife and then cut it into four pieces. One such piece is consumed (chewed) with lime and betel leaf. Ripe fruits are generally harvested for a large scale sale.
The nut is also consumed after curing in water. The fresh fruits with husk (little less ripe) are cured in flowing water for some period. The process helps in loosening the husk. This way husk can come out from the nut by hand.
About 22% of husk still remains over which is removed with the help of knife. The nut is consumed along with lime and betel leaf and relished by the local Khasis. The curing is mainly for taste, improvement in colour and easy removal of husk. These practices are common in Meghalaya.
Assam and Tripura also grow areca nut extensively. In Tripura state the dry nut is consumed in small pieces with betel leaf and lime. No special type of curing is practiced in the state. Nuts are cured in Upper Assam by keeping the fruits in the pits. A circular pit is dug in the open area around the houses. The size of the pits varies from 2 to 3 m in diameter and 3 to 4 m in depth as required.
The pit is plastered with leaves and cow-dung at the bottom and inside on the wall. The freshly harvested fruits are charged normally in April and early May for curing. The upper half- meter layer is again filled with leaves, cow-dung up to the ground level. Then the pits are opened in December to January for sale and consumption of the cured produce.
Another popular method of processing of nuts in Assam consists of boiling of the immature fruit for about 2 hours after the removal of husk and drying in the sun. The produce is known as Chikani. Such fruits are relished by local Assamese people.
The modern methods of nut-producing consists of reducing the nut into slices, wafers or grits, followed by drying, flavouring, scenting, colouring and softening. Such processed nut is chewed with betel leaf and eaten sometimes directly.
Curing of Areca Nut in Meghalaya:
People of Meghalaya are fond of taking fresh fruit instead of processed one. But fresh fruits are not available round the year as the harvesting periods in the areas are November to December and March to April.
Some of the produce is disposed off in the market, whereas slightly immature fruits are cured to improve their quality. The Khasi cure the areca nut in the flowing water. The technique might have been developed by the trial and error method. In olden day a tribal family used to store the areca nuts in earthen pots of water for maintaining their moisture and freshness.
Components of Areca Nut:
A typical curing of Areca nut consists of the following components:
i. Curing Pond:
A pond for the curing of Areca nut is constructed of stones and masonry. It is normally in the size of 15m length, 10m width and 2.5m depth. Such a pond can take 150 baskets of nuts. The size and shape of a pond may vary as per requirement and the land scape of the area; however the depth remains the same.
ii. Water Flowing Channel:
The perennial stream is the main requisite for the location of a pond. In the typical arrangement, water flow is diverted from the upstream of the nearby pond at one end and outlet is kept diagonally opposite of the inlet. The water level maintained 2.35 m from the bottom with the continuous flow.
iii. Holding Basket:
The holding baskets are locally (Nongpriang village) prepared of bamboo by matting of the size of 1 m diameter a top and 2.65 m height with the square bottom of 0.65m. The matting is done with 1 cm bamboo strips by keeping the 3 cm perforation. Each basket has a capacity to hold 1200 kg of areca nut which is equivalent to 12 gunny bags of areca nut.
iv. Raising Basket:
A small bamboo basket is used for raising the cured fruit from the pond. This basket is matted in the size of 36 cm diameter a top, 30 cm high with the square base of 16 cm.
The Method:
The pond is at first fragmented into the square of 90 cm x 90 cm each at the top with frames made of the strong bamboo. Thus the holding baskets of 1 m diameter when inserted into these squares could be reduced to that size. The bamboo frames hold the individual baskets and keep them vertical. These baskets are filled with the freshly harvested areca nut. Fruits normally float on the water.
The baskets are therefore covered with jute clothes and stone weights are kept over them in order to ensure the proper curing. Once the areca nuts are charged into the holding baskets, then they are not disturbed till the curing is completed.
No special care is required except the maintenance of the water level of the pond and water flow. The minimum water flow is assured (36 lit/min) to prevent the fruits from being spoiled. Excess water flow is considered good for keeping the fruit fresh.
The criteria for adequate curing are:
(i) Yellow colour turns prominently bright yellow; and
(ii) The husk gets freed from kernels.
The normal curing time is around 4 to 5 months. The fruits are then taken out from the pond. The fruits are sometimes cured for one and half months and disposed as and when demand for them arises. Once the fruits are raised from one holding basket then that basket should be completely raised out otherwise the rest of the fruits will be spoiled. The loss in curing is generally 15-30% of the total weight.
The loss can be minimized by keeping the same lot in one basket. The units of fresh fruits and nuts in one kg amount to 42 and 75 in number respectively. The dry nuts in one kg however amount to 135 in number. Curing improves colour, taste and freshness of the nut. Cured kernels are less astringent and are better to chew and taste.
Preservation of Fruits:
Fully ripe arecanuts after preserving are used throughout the year. These are quite very popular in Kerala and Assam. In Assam, fresh fruits are preserved in thick layers of mud. This product is known as Bura Tamul. In Kerala, fresh fruits are stored by steeping in water, resulting in discolouration of outer husk and foul smell due to bacterial attack but the inner core is well preserved. This product is known as Neettadakka.
Use of a solution containing sodium benzoate (0.1 %) and potassium meta-bisulphate (0.2%) acidified to a pH of 3.5-4.0 with hydrochloric acid for steeping ripe nuts after initial heat blanching is suggested to eliminate the foul smell and improve the quality of nuts.
Dried Ripe Nuts:
The most popular trade form of arecanut is dried whole nut known as Chali or Kottapak. Ripe nuts are dried in the sun for 35-40 days, dehusked and marketed as whole nuts. The optimum moisture content is around 12%. Inadequate drying results in fungal infection and in a poor quality product. Depending on size, different grades of decrease order are Moti, Srivardhan, Jamnagar and Jini.
The main producing states of Chali are Kerala, Karnataka, Assam and Maharashtra. To facilitate drying and dehusking, the fruits are cut longitudinally into 2 halves and sun-dried for 10 days. The kernels are scooped out and given a final drying. This product, known as Pareha, is popular in Kerala and Karnataka.
Mechanical driers are also used to make Chali. Drying takes 60-70 hours over a period of 7-8 days at 45° – 75° C. The dehusking can be done using a manually-operated arecanut dehusker developed by CPCRI, Kasaragod. About 40 kg chali can be made within a period of 8 hours.
Kalipak:
It is another important processed product of arecanut. Kerala and Karnataka are main producers of Kalipak. Tender nuts of 6-7 months are dehusked, cut into pieces, boiled with water or a diluted extract from previous boiling, coated with kali and dried.
Kali coating can be repeated 3-4 times to get a glossy appearance. Kali is the concentrated extract obtained after 3-4 batches of boiling. The kalipak is known by different names depending on number, shape and size of the cuts.
Api or unde (without any cuts), batlu (transverse cut into halves), choor (several longitudinal cuts), podi (both longitudinal and transverse cuts) and erazel (transverse thin slices), lylon is another variety made from green nuts which are cut transversely into 5-6 discs and without kali coating.
During preparation of kalipak, the tannin content is reduced substantially. A well-dried product with a dark brown colour, glossy appearance, crisp chewing feel, well-toned astringency and absence of over-mature nuts are rated superior.
Scented Supari:
It is made both from chali and kalipak. Chali supari is more popular. The dried nuts are broken into bits, blended with spices and flavour mixture and packed in butter paper. Instead of raw spices, essential oils are used for easy blending, with coconut gratings to avoid microbial growth. Saccharin is occasionally used for sweetening. Rose essence and menthol are commonly used for flavouring.
Uses of Areca-Nut Constituents and Byproducts:
i. Tannins:
Polyphenols or tannins from the major constituent of the nut. Tender nut contains tannins 30 – 37%, while ripe nuts have only 16-22%. The areca tannins obtained as byproduct from tender nut processing can be utilized for drying clothes, leather, rope, for making black writing ink along with ferrous sulphate, as an adhesive in plywood manufacture and even as food colour.
ii. Fat:
The nuts contain 8-12% fat, which is extractable with organic solvents like hexane or chloroform. The fat is rich in myristic acid and can be a good source of myristic acid and its derivatives. Refining of fat with alkali makes it edible. It can be mixed with cocoa fat for confectionery products and as an extender to cocoa butter for various products. It can be a substitute for vanaspati in preparations of sweets and biscuits.
iii. Alkaloids:
Arecanut has 1.5% of alkaloids such as arecoline, arecaidine guvacine, idoguvacine and guvacolidine. Of them, arecoline alone accounts for 0.24 %. They possess anthelmintic property and are effective against tapeworms and roundworms. It is also used as a CNS depressant drug. It has got anti-bacterial property and inhibits the growth of Escherichia coli, Staphylococcus typhi and Staphylococcus aureus.
iv. Areca Husk:
The husk of arecanut constitutes 60-80% of the total weight of fresh nut. Several processes have been developed for utilization of areca husk for making hard boards, plastic boards and brown wrapping paper. The husk fibre extracted by soaking in water for 3 weeks and beating with a mallet can be used for thick boards, fluffy cushions and non-woven fabrics. It can be a good source of furfural and xylose for industrial applications.
v. Areca Stem and Leaf Sheath:
Arecanut stem is a useful building material. Its timber can be used for making a variety of elegant utility articles like rulers, shelves and waste-paper baskets, due to its hardness. Hollow stem can be used as drainage and irrigation pipes.
A process has been developed at CPCRI, Kasaragod, for making ply boards from leaf sheath for tea chest, snit case and file board manufacture. The CFTRI, Mysore, has developed a machine for making cups and throw-away plates which can substitute the paper plates.