Below: The cashew nut or kernel forms within an outer shell at the end
of a fruit known around the world as the cashew “apple”.


Intermediate Development Group (ITDG), who developed a special oven to dry the cashews

Cashew News

Earth Report Index - Earth Report archives  - Hard nut to crack

Embrapa released a new, early dwarf cashew clone, named END 157, the result of exacting breeding techniques. This clone considerably increases cashew grove productivity and is recommended for irrigated commercial plantations. A major advantage is its suitability for being consumed raw. Secretariat for International Cooperation, Phone: + 55 (61) 448-4338, Email: sci@embrapa.br

http://www.youtube.com/watch?v=45Mxdan4M3o
 

DRYLAND TECHNIQUES AND WATER RESOURCES
We found out that each and every cashew nut is the seed from a cashew fruit. Each seed must be opened, the poison oil burned off, and the individual nut processed. No wonder cashews are so expensive!

Below: Peter Shearer
The cashew grows into quite a large tree even on poor soils with
low rainfall, but requires irrigation and fertiliser to maximise yields.


Cashews Australia
Some of the cashews growing wild around North Queensland are the legacies of fortune-seeking Malays who brought the trees to Australia during the Palmer River goldrush. “It's not surprising that the cashews have survived in the area for almost a century. The cashew tree does not require a great deal of maintenance and,” according to Cashews Australia’s Peter Shearer, “there are pockets of land around northern Australia that are ideally suited to cashews as a large-scale, horticultural crop

Getting Started
The reliable growth and early production of the cashew in North Queensland initially drew Peter to the potential of crop. In 1988, he was looking for opportunities to diversify his macadamia plantation. He secured planting material from the Queensland Department of Primary Industries ’ Kamarunga Research Station near Cairns, and planted his first cashews in 1989 on his macadamia plantation near Mareeba. These trees bore their first fruit within a year of being planted. This early production, coupled with the production of cashew fruit and nuts earlier in the year than macadamias, impressed Peter of the potential of cashews as a viable alternative crop, allowing a more rounded usage of his farm equipment. The Cadju - Tanzania Cashew
Below: Cashews Australia’s on-farm primary processing facilities at Dimbulah, North Queensland. - National Research Centre for Cashew - TechnoServe/Ghana

AUSTRALIAN NUT FARMER PROMISES RICH HARVEST
April 28, 1999 Australian Associated Press

CAIRNS, -- Australia's biggest nut farmer, former menswear manufacturer Peter Shearer, is, according to this story, cultivating a new hybrid cashew in north Queensland which gives a four-fold production increase.

The story notes that the huge world demand for cashews has boosted wholesale prices from $8.30 to $12.20 a kilo in six months, motivating the Mareeba farmer to invest $2 million in the world's first automated processing plant for his company, Cashew Australia. The story also notes that seven million dollars invested over 10 years in research by state and federal governments had produced 3800 new cashew varieties, with 12 of the superior varieties going into new developments.
The cashew apple is harvested as a fresh fruit and for juice in its native Brazil.

North Queensland's hot, humid weather provides perfect growing conditions for the company's 35,000 trees currently being harvested. In July the company plans to plant 158,000 new hybrid trees which, aided by a revolutionary green ant pest eradication program, will be grown organically for health food shops in Europe and the USA.

The hybrid trees produce jumbo-sized nuts which are attracting a 25 per cent world premium.

African Cashewnut

Earthship Biotecture Buildings

The GDFC had plans to replace the old and senile trees with high yielding Vengurla 4 seedlings, investing Rs 26 crore. Planting 200 trees per hectare (hectare = 2.471 acres or 80 trees per acre.), the estimated yield was 1200 kgs (545 Pounds)
(kgs = Kilograms or 2.2 pounds) per hectare, increasing its production from the present 1.5 kgs per tree to six kgs per tree, with annual income of Rs 30 crore.
80 trees per acre results in 545 pounds of cashews (6.81 pounds per tree).

Folklore, medicinal and non-food uses.
The fruit bark juice and the nut oil are both said to be folk remedies for calluses, corns, and warts, cancerous ulcers, and even elephantiasis. Anacardol and anacardic acid have shown some activity against Walker carcinosarcoma 256. Decoction of the astringent bark given for severe diarrhea and thrush. Old leaves are applied to skin afflictions and burns (tannin applied to burns is liepatocarcinogenic). Oily substance from pericarp used for cracks on the feet. Cuna Indians used the bark in herb teas for asthma, colds,and congestion. The seed oil is believed to be alexeritic and amebicidal; used to treat gingivitis, malaria, and syphilitic ulcers. Ayurvedic medicin recommends the fruit for anthelmintic, aphrodisiac, ascites, dysentery, fever, inappetence, leucoderma, piles, tumors, and obstinate ulcers. In the Gold Coast, the bark and leaves are used for sore gums and toothache. Juice of the fruit is used for hemoptysis. Sap discutient, fungicidal, repellent. Leaf decoction gargled for sore throat. Cubans use the resin for cold treatments. The plant exhibits hypoglycemic acitivity. In Malaya, the bark decoction is used for diarrhea. In Indonesia, older leaves are poulticed onto burns and skin diseases. Juice from the apple is used to treat quinsy in Indonesia, dysentery in the Philippines.
* Gum from fruit stems is used as a varnish for books and woodwork - protects from insects and ants.
* Extracts show hypoglycemic activity experimentally.
* Anacardic acid - in oil from fruit, has antibiotic activity against gram+ bacteria. Also used against leprosy and ringworm.

Botanical description
Plant: Bushy, low-branched tree to 12 m in height and width; lower limbs often bend to touch the ground. Propagation by seed, grafting, layering, cuttings; Fruit production in 4-5 yr from seed, 2-3 yr from vegetative propagation.

Flowers: are tiny, pinkish, borne terminally on panicles. Flowers can be male, female, or perfect on the same inflorescence.

Fruit: is a 1 inch nut, shaped like a small boxing glove, hanging below a fleshy, swollen peduncle (receptacle) called the "cashew apple". Fruit borne singly or in small clusters. Fruit matures in 60-90 days. Apple is 2-4.5 inches in length, pear-shaped, yellow or red skin covering the fibrous, juicy, astringent yellow pulp.

Nut shell contains toxic oil which must be roasted to detoxify; can cause dermatitis. Sometimes, the apple is utilized and nut thrown away (!). In commercial plantations, apple and nut are allowed to drop together, and nut is twisted off, leaving the apple on ground for grazing livestock. Nuts can be roasted in fire like marshmallows, where they catch flame and burn-off oils.

General Culture
Soil pH should be acid 4.5-6.5.
Tolerant of poor soils and seasonally dry conditions.
Contribution to diet, food uses

Nuts rich in protein and oil; the apple is extremely high in vitamin C (>500% of RDA!) and other minerals. Apple may be consumed fresh or partially dried and candied, as in the Dominican Republic and India.

Dietary value, per 100 gram edible portion:
--------------------------------------------------------------------------------
Water (%) ............................................ 3.6
Calories ............................................ 578
Protein (%) ......................................... 18.5
Fat (%) ............................................... 48.2
Carbohydrates (%) ............................... 27
Crude Fiber (%) .................................... 1.3
% of US RDA*

Vitamin A ............................................ ---
Thiamin, B1 ....................................... 45
Riboflavin, B2 ..................................... 12
Niacin ............................................... 12
Vitamic C .......................................... ---
Calcium .............................................. 0.2
Phosphorus ........................................ 5.8
Iron .................................................. 50
Sodium ............................................. ---
Potassium ........................................ 12 --------------------------------------------------------------------------------
* Percent of recommended daily allowance set by FDA, assuming a 154 lb male adult, 2700 calories per day
Minerals
Cashew kernel is a rich source for minerals like calcium, phosphorus and iron. Those minerals in their organical form protect our physical health and nervous system.

Carbohydrates
Cashew kernel has a very low content of carbohydrates, as little as 1% of soluble sugar. Such a quantity is sufficient to give a pleasant taste without creating excess energy. Cashew is , therefore, non-fattening and can be safely consumed by those suffering from obesity and diabetes.  Cashew is rich in vitamins of B group, especially thiamine which is useful for stimulation of appetite and nervous system. It may be used as a food medicine for loss of hunger, general depression, nervous weakness and scurvy. It is also a rich source of riboflavin which keeps the body active, gay and energetic. Cashew is useful in anaemia, being rich in iron. Its regular use is beneficial in the treatment of gas trouble, cough and urinary and liver disorders.

Elimane Dramé Pioneers Local Cashew Processing
Mr. Dramé is already thinking about the future of the business and how to increase his capacity by re-investing his profits to acquire more processing equipment, and a more sophisticated packaging machine so that he can better market his products. When he saturates his local market, EnterpriseWorks has more commercial contacts for him both within Senegal and internationally, and he is developing contacts of his own via the internet with traders in Taiwan, Morocco, and Tunisia. His long-term goal is the export market.

Uses

Many parts of the cashew plant are used. The cashew "apple," the enlarged fully ripe, fruit may be eaten raw, or preserved as jam or sweetmeat. Alcohol production is another use of the apple. It is used to flavor Madeira wine and various other liquors. The juice is made into a beverage (Brazil cajuado) or fermented into a wine. Ian Wallace, writing to ECHO from Guinea-Bissau, says, "Cashew has greatly aggravated another social problem—drunkenness. The squeezed fruit juice ferments quickly, without the need for people to do anything, making a strong alcoholic drink in days. The cashew wine is available in far greater quantities than palm wine. Cashew season sees a marked increase in drunkenness." In Mozambique there was a time when cashew cultivation was actually prohibited because of the drinking problems it caused (Morton, 1972).

Fruits or seeds of the cashew are consumed whole, roasted, shelled and salted, in Madeira wine, or mixed in chocolates. Shelling the roasted fruits yields the cashew nut of commerce. Seeds yield about 45% of a pale yellow, bland, edible oil, resembling almond oil. From the shells or hulls is extracted a black, acrid, powerful vesicant oil, used as a preservative and water-proofing agent in insulating varnishes, in manufacture of typewriter rolls, in oil- and acid-proof cements and tiles, in brake-linings (The cashew nut shell liquid (CNSL) is used in brake linings of cars because it absorbs heat efficiently. CNSL is also used in preserving and waterproofing, and in paints, enamels and lacquers. The CNSL also has been used to treat scurvy, warts, ringworm, and even for tattooing.), and is an excellent lubricant in magneto armatures in airplanes, and for termite proofing timbers. Timber is used in furniture making, boat building, packing cases and in the production of charcoal. Bark used in tanning. Stems exude a clear gum, Cashawa gum, used in pharmaceuticals and as substitute for gum arabic. Juice turns black on exposure to air and provides an indelible ink. Along the coast of Orissa, shelter belts and wind breaks, planted to stabilize sand dunes and protect the adjacent fertile agricultural land from drifting sand, have yielded economic cashew crops 5 years after planting (Patro and Behera, 1979).

Other parts of the tree are used medicinally to cure sore throats, chronic dysentery and diarrhea. The bark is chewed for sore gums and toothache. Leaves can be crushed for a poultice for skin ailments. Cashew brandy is used as a liniment for rheumatism and neuralgia.

Cultivation

Cashew germinates slowly and poorly; several nuts are usually planted to the hole and thinned later. Propagation is generally by seeds, but may be vegetative from grafting, air-layering or inarching. Planting should be done in situ (in its proper position.) as cashew seedlings do not transplant easily. Recommended spacing is 10 x 10 m, thinned to 20 x 20 m after about 10 years, with maximum planting of 250 trees/ha. Once established, field needs little care. Intercropping may be done the first few years, with cotton, peanut, or yams. Fruits are produced after three years, during which lower branches and suckers are removed. Full production is attained by 10th year and continues to bear until about 30 years old. In dry areas, like Tanzania, flowering occurs in dry season, and fruits mature in 2–3 months. Flowers and fruits in various degrees of development are often present in same panicle.

Harvesting

From flowering stage to ripe fruit requires about 3 months. Mature fruit falls to the ground where the 'apple' dries away. In wet weather, they are gathered each day and dried for 1–3 days. Mechanical means for shelling have been unsuccessful, so hand labor is required. Cashews are usually roasted in the shell (to make it brittle and oil less blistering), cracked, and nuts removed and vacuum packed. In India part of nuts are harvested from wild trees by people who augment their meager income from other crops grown on poor land. Kernels extracted by people skilled in breaking open the shells with wooden hammers without breaking the kernels. Nuts are separated from the fleshy pedicel and receptacle, seed coat removed by hand, and nuts dried. Fresh green nuts from Africa and the islands off southern India are shipped to precessing plants in Western India. Cashew tree has few serious diseases or pests. Flowers are visited by flies,  bees (original Palmolive dishwashing liquid will disable bees), ants and other insects, which may serve as pollinators. Artificial pollination is practiced in some areas. Four insects are considered major pests: the white fly, a caterpillar, a red beetle, and a thripe.

Energy

A perennial species, the cashew has already, in the past, yielded alcohol from the "apple," oil from the nut, and charcoal from the wood. The "apples" (ca 30–35 kg per tree per annum) yield each 20–25 cc juice, which, rich in sugar, was once fermented in India for alcohol production.

The old way of processing cashew nuts involves a tedious seven-step process. The nuts are sun-dried for a day or two on the drying pavement - involving a lot of prayer for good weather. Then the nuts' shells are split, the kernels are extracted and empty shells and rotten nuts are discarded. The kernels are then oven-dried to make them crunchier and more palatable, then cooled in jute sacks. The cooled kernels have a loose covering of skin that is peeled away to reveal the smooth texture of the final product.
While cashew nuts can be processed with very simple tools, the nut output using the old method does not meet global standards. The nuts processed the old way are often split and sometimes pungent in taste, making them unattractive and unpalatable to potential buyers, flavor and quality also fluctuated.

The DOST Region X office, through TAPI, approved a soft loan of P275,000 for the LWSHA to acquire new technology to process cashew nuts. The equipment included a steam roaster, a boiler, a heat exchanger, aluminum trays, whole nutcrackers and a sorting table. For the first time, the women were able to produce processed cashew kernels that are intact, with a taste comparable to imported cashews sold in cans and foil packs. The DOST Region X office again assisted LWSHA later by fabricating for them a cashew nut dryer, making the women less dependent of the fickleness of the weather.

Packing of cashew kernels in an atmosphere of carbon dioxide
This process in which the air in the container is removed and replaced with carbon dioxide prevented the development of infestation and made it possible for cashew kernels to be stored without fear of deterioration in quality for long periods and enabled large scale shipments to be made to various foreign countries.

Processing
ROASTING :-

The roasting of Raw Cashewnut is done by steam roasting process. A specially designed steam boiler is employed for this purpose. The raw cashewnuts are fed into this boiler and kept under atmosphere of steam for 30 minutes. The Steam Roasted nuts are then spread in to the floor for cooling. The main purpose of roasting is to avoid breakage of kernels during the cutting process.

CUTTING PROCESS :-

The roasted cashewnuts are fed into the hand operated cutting machines to separate kernels from the shells. The cutting machines are operated by small blades and springs. The entire process is manual and is usually handled by ladies. Each women can work around 80 kgs. of Raw Cashewnuts per day.

HOT CHAMBER :-

Cashew Kernels from cutting process are kept in the Hot Chamber for around 8 to 10 hours. The Cashew Kernels usually contains 8 to 10% moisture which requires to be dried for removal of testa.

 The hot air is made to pass through the Hallow walls of the bricks. The kernels which are spread in the sizers will be dried in around 8 to 10 hours. Usually the temperature of the Chamber is kept at 80 to 90 degree centigrade.

PEELING :-

The outer red testa, which is attached to the Kernels will be peeled off with a small knife. Major portion of workers will have to be employed in this section. The entire process is manual.

GRADING :-

The peeled cashew kernels are graded according to its size, colour and its maturity. There are around 22 grades of cashew kernels and a specification of each grade is laid down by the Cashew Export Promotion Council.

Best fuels
It is one of the best fuels. It is mainly used by cashew industries, tile manufacturing units and others. It is possible to use the cashew shell oil cake as conventional boiler fuel. The oil cake is also suitable feedstock for generating producer gas both for boiler and IC engines.

The effect of nitrogen on cashew  in north Queensland 1995-99

1.5. PACKAGING

Packaging is done in Cartons and Corvac (vacuum aluminized bag with capacity for 50 lbs of cashew nuts). The 50 lbs aluminum bags goes inside the cartons and there are 700 cartons in a 20 feet container which is equivalent to 35,000 lbs of cashew nuts.

In the back of the packing room, there is an aluminized bag sealing machine. Its purpose is automatically air-tight seal, inject carbon dioxide (CO2) and, finally, seal the bag containing the cashews with a fusion process. The machine on the left-hand side of the photo is an analogical scale with an adjusted capacity for 25 lbs, that is, half a carton (box) of cashews.

The equipment is called the "Pneumatic Separator". Its main purpose is to remove small cashews fragments and skin, according to an adjustment of intensity and air volume that performs this separation by density. The machine is also known as "Ventiladora" ("Fan") in common language.

In the foreground, we can see a group of silos that store the cashew nuts "in natura", already cooked in their own juice, that is, CNSL (LCC). The silos serve as cooling containers, given that they have air intakes in their bottoms for this purpose. In the background, the photo shows metal boxes containing high-rotation disks. This machine is known as the Decorticador", and its purpose is to break the nut peel, already cooled in the previous silos, and remove the cashews. Centrifugal force impacts the nut, which then opens, releasing the cashew itself.

This is a view of a battery of aligned silos, used at the beginning of the process with the only purpose of humidifying the cashew nuts "in natura".

The cashew nut manufacturing process stage is also called "Nut Treatment". Here, the previously washed nut is placed in a machine that can be seen in the background, on the right-hand side of the photo. The water jets and whirls of this machine, considered very important in this process, remove all impurities.

The time that the nut rests in these huge silos represents a variable with direct influence on the quality and yield of the treated nut.

Here we can see manual selection mats. The complete cashew nut classification and selection process goes through a stage of high level of handicraft, performed by female workers on these mats. The cashews are transported on PVC (a type of canvas/fiber) conveyor belts with an approximate speed of 6 meters/minute. Lighting is provided by fluorescent lamps. daylight. On the sides of the mats, female workers remove the reject, allowing the passage of only the very best production.

Insect Pollination Of Cultivated Crop Plants

The cashew 'apple' is a bell-shaped pseudocarp which holds the "nut" below it. The "apple" (or fruit) is often used for juice, preserves, candy, and jam in Asia. The first step in drying the fruit is to boil the apples in salty water for 15 minutes to remove the bitter taste that is unpleasant to some. Then the apples are perforated and compressed in specially cured wooden devices. The compressed apples are then boiled in sugar for two hours. Some 350 kg of sugar are used with every 1,000 apples with enough water to cover the apples. The sugar is re-used twice.

The boiled apples are then dried in a solar drier. The apples are put in 1.2m x 0.6 m wire trays to a depth of 2.5 cm, inside a 1.5 m x 1.2 m wooden cabinet which is covered with plastic film. Underneath the wire trays there is a black collector plate. The cabinet is inclined at 80 °, set toward the east in the morning and moved during the day. The apples are dried in one day and have a shelf-life of 6-8 months.

This has been extremely successful. By 1985, over 5,000 kg of cashew produce had been marketed and orders for 1987 were more than 35,000 kg. This provides employment for 2,000 families at £5.00 (rather than £1.50) a day.

 
Cashew Nut Butter Cookies