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Argan

I. GENERAL

COMMON NAME

Argan

BOTANICAL NAME

Argania sideroxylon, Argania spinosa

FAMILY

Sapotaceae

OTHER NAMES

Arga, Argaria, Arganier, Arjardin, Iron wood, Moroccon iron-wood tree

CULTIVATION CONDITIONS

The tree grows wild in south western Morocco over an area of some 740 000 Ha. It is well suited to calcareous soils and semi desert conditions. Modern developments have destroyed much of the previously extensive forests, protection is urged. The region has an annual rainfall of 100-m.

MAJOR PRODUCING COUNTRIES

MOROCCO

YIELD AND DESCRIPTION

The tree begins to bear fruit when it is five years old and has a life span of 125-150 years. The olive sized fruit are round to oval and turn bright yellow when ripe. Each fruit bears one to three oval brown smooth seeds, about 2 cm long. The seeds contain up to 50% of a light brown oil (Farines). Inside each seed testa is a white, bitter oil rich kernel. Production is at its maximum when the tree is 60 years old. The average yield of fruit per tree is estimated to be 8 kg per annum. The Argan tree has the ability to retreat into a state of dormancy for a prolonged period in the advent of drought conditions and thus does not necessarily bear fruit every year (Mellado). The pulp of the fruit around the seed is reported to contain 20% sugars, 13% cellulose, 6% protein and 2% fat (Morton).

MAIN USES

In addition to its importance as a source of edible (cooking) oil the argan tree is also a major source of forage for sheep, goats and cattle. The timber is used as fuel. Protection areas have now been established to prevent this use of the tree. At a local level the wood is still used to make ploughs, wooden implements and utensils (Mellado).

II. AGRICULTURAL ASPECTS

CULTIVATION

The tree is not grown in plantations although its possible role in reforestation in Spain has been studied (Montoya). The seed" tend to germinate poorly without some assistance, those that survive having usually passed through the digestion tracts of grazing animals, particularly goats. Strict conservation measures have been implemented to prevent the threat of extinction caused by clearance, its poor germination quality and the fact that the timber is an excellent fuel (Mellado).

HARVESTING PERIOD

Harvesting takes place during September.

HARVESTING METHODS

Three main methods are used to harvest argan fruit, two of which involve the use of animals. Grazing goats sometimes eat the fallen fruits, spitting out the seeds which are then gathered up by hand. Camels are also fed the fruits, the seeds are indigestible and pass through the animal to be excreted. These seeds are then gathered from the dung. An alternative harvesting method is simply to shake the tree causing the fruits to fall to the ground for manual collection.

III. POST HARVEST TREATMENT. PRESERVATION AND STORAGE

PRE-TREATMENT

The fruits are sun dried until they reach approximately 50% of their original weight. The fruit is hit with a stone and the outer dry pulp separates cleanly from the inner nut.

IV. PROCESSING

PROCESSING METHOD

The nuts are cracked by hand using a stone hammer and anvil and the kernels removed.

OIL EXTRACTION

Traditional methods of processing involve the seed being roasted and then ground manually to a paste. Tepid water is added to the mixture and the oil which floats to the surface decanted off. More modern methods of oil extraction use small oil presses, typically olive presses. The first pressing produces edible oil, the second cooking oil. (Mellado).

MAJOR FATTY ACIDS OF OIL

(Source: Mellado and Morton)

LOCAL PRODUCTS

The oil is mixed with almonds and honey to make an almond butter known locally as "amalou". Mixed with wheat germ and honey it makes a breakfast gruel locally called "sematar" (Mellado).

EQUIPMENT

Roasting pans, grinding mills, pestles and mortars and small expellers. There is a lack of identifiable information about the following areas: GENERAL, production; AGRICULTURAL ASPECTS, major pests and diseases; POST HARVEST, preservation, storage and equipment; PROCESSING, processing methods, by products, nomenclature of products; OIL EXTRACTION, By products.

BIBLIOGRAPHY

FARINES, M. SOULIER, J. CHARROUF, SOULIER, R. "Study of the Seed Oil from Argania spinosa (L.) Sapotaceae. I. The glyceride fraction." Revue Francaise des Corps Gras. 1984, 31 : 7/8, 283-286.

FELLAT ZARROUK K, SMOUGHHEN. S, MAURIN. R, "A Study of the Pulp of the Fruit of the Argan tree ( Argania spinosa ) of Morocco. Fats and Latex'., Actes de l'Institut Agronomique et Veterinaire, II, 1987, 7:3-4, 17-22.

MELLADO. J, 'Argan Forest Destruction in Morocco'., Oryx. 1989,23: 2, 87-93.

MONTOYA OLIVER, J. H. "Potential Silvopastoral y de repoblacion en Espana"., Anales del Instituto de Investigaciones Agrarias, Forestal, Spain, 1984. No.8, 141-152

MORTON, J. F. VOSS, G.L. "The Argan Tree (Argania sideroxylon, Sapotaceae) A Desert Source of Edible Oil", Economic Botany, Vol 41, 2, pp.221-233, 1987.

Avocado

I. GENERAL

COMMON NAME

Avocado

BOTANICAL NAME

Persea americana

FAMILY

Laureacea

OTHER NAMES

Palta

HABITAT

Temperate to Tropical

MAJOR PRODUCING COUNTRIES

Native to Central and S. America. Now widely distributed in tropical and subtropical countries worldwide.

Mexico, USA, Brazil, Dominican Republic, Israel

YIELD AND DESCRIPTION

While only one species is usually recognized there are 3 ecological races; Mexican, Guatemalan and West Indian. The Mexican, the most hardy, has the highest pulp oil content, up to 30% but is of little economic importance except for its hybrids. The Guatemalan, which is less resistant to cold, has a medium oil content of 8-10% while the tropical West Indian has only 3-10% oil in the pulp. Inter-racial hybrids are grown commercially (Purseglove).

The avocado tree grows to a height of 20m and bears the well known fruit which can weigh up to 1.5kg. The single seeded fruit 7-20cm long has a leathery skin which ranges from yellow-green to purple in colour. The edible mesocarp or pulp is yellow to yellow-green in colour and has a buttery consistency.

The tree starts to bear fruit when 3-6 years old and has a productive life of 25-35 years.

The pulp contains 65-80% moisture, 1-4% protein and 3-30% oil. The kernels contain little oil, about 1%. It has been shown that oil content increases dramatically in the last months of ripening (Human). In S. Africa fruit is picked for fresh consumption when the oil content is about 8% but at this stage of ripeness it is not suitable for oil extraction. Oil is generally extracted from culled fruit that are left to fully ripen after harvesting (Human).

In 1981 world production of avocado oil was 300 000 T.

MAIN USES

Avocado fruit is mainly for fresh consumption. It is also sold frozen with lemon juice and spices (Guacamole), as a cheese-like fermented food and as pulp for use in ice cream (Hilditch). (Jacobsberg).

Avocado oil is being strongly promoted for cosmetics and, after refining as a high price food oil. It has also been shown to be a most effective sun screen oil. In 1976 the US. FDA register recorded 240 cosmetic products containing avocado oil at levels of 0.1- 50% (Swisher).

II AGRICULTURAL ASPECTS

CULTIVATION

Avocado trees can be grown from seed but are better propagated vegetatively. The plants are transferred to orchards at 6-9 months. The normal planting distance is 20-40 ft. Maturity can be tested by oil content (Purseglove).

Yields are variable between 100-500 fruits per tree. Good orchards in California give 3-6 tons of fruit/ acre/annum (Purseglove).

HARVESTING PERIOD

As required

DISEASES AND PESTS

The most serious disease is root rot caused by Phytophthora cinnamomi. Other serious diseases are Cercospora spot, Anthracnose, and Scab. Scale insects, mealy-bugs and mites may cause damage. The sugar cane root weevil causes damage in Puerto Rico.

HARVESTING METHODS

Hand picking is most common.

III POST HARVEST PRE-TREATMENT. PROCESSING, STORAGE

PRE-TREATMENT

After harvesting the fruit should be allowed to ripen fully to give maximum oil yield. Depending on the method to be used for oil extraction the fruit may then be opened and, after removing the seed, sun dried.

IV PROCESING

OIL EXTRACTION

A number of methods have been proposed including mashing the pulp and after boiling skimming off the oil, high pressure pressing of dried slices, solvent extraction, expellers, presses and centrifugal extraction.

Another proposed method involves rendering; heating the pulp in avocado oil and evaporating off the moisture. The remaining slurry of oil and plant material is then pressed. Small scale trials showed that 57% of the oil could be decanted off after rendering and after subsequent pressing oil recoveries of 94% were achieved (Human). The addition of chalk, which precipitates the fruit pectins, has been found to improve oil release from the cells (Hilditch).

The crude oil is dark green/brown in colour, red under reflected light due to its high chlorophyll content and may be refined by alkali refining, bleaching, deodorizing and winterising. If very old rotten fruit is used as a raw material the oil may need alkali refining to remove FFA (Human).

Avocado oil has one major disadvantage in so far as it develops a bitter taste if heated. It is considered that treatment to overcome this defect would be very difficult (Human).

MAJOR FATTY ACID COMPOSITION OF OIL

The oil composition varies greatly,

(Source: Hilditch)

EQUIPMENT

Presses, expellers, centrifuges, solvent extraction plants, refining and filtering equipment.

NOMENCLATURE OF PRODUCTS

There is a lack of identifiable information on details of oil extraction methods and refining methods in use.

BIBLIOGRAPHY

APARTO,A.R, "Prototype of a pilot scale model of an avocado oil extraction unit", NSDB Tech. J., 1981, Vol 6, (3), p 7-12

GALEB SALOMAN,E.A; DRAETTA,I.dos S.; IADEROZA,M.; FERREIRA,V.L.P.; SOLER,M.P. "Industrial processing of avocados for production of edible products". Boletin do Instituto de Tecnologia de Alimentos, Brazil. Vol 17, No 2, pp 147-180, 1980.

HILDITCH.T.P., Chemical Contribution of natural fats. P147

HUMAN,T.P.", Oil as a byproduct of the avocado", S.Afr., Avocado Growers 'Assoc.Yrb. Vol 10, 1987, pp 159-162.

JACOBSBERG.B., "Avocado Oil: A Literature Survey", Belgian Journal of Food Chemistry and Biotechnology., Vol. 43, No 4, 1988, pp 115-124,

PURSEGLOVE pp 193-8

SOUTHWELL, K.H, HARRIS,R.V, SWETMAN,A.A, "Extraction and refining of oil obtained from dried avocado fruit using a small expeller", Tropical Science, 1990, Vol 30, (2), p. 121131

SWISHER, H.E, "Avocado oil, from food use to skin care", J. American Oil Chemists Soc., 1988, Vol 65 ,(11), p 1704-1706.

WERMAN, M.J, NEEMAN,I, "Avocado oil production and chemical charcteristics", J. American Oil Chemists Soc., 1988, Vol.64, (2), p. 229-232

Babassu palm

I. GENERAL

COMMON NAME

Babassu Palm

BOTANICAL NAME

Orbignya martiana

Orbignya oleifera

FAMILY

Palmaceae

OTHER NAMES

Babacu, Coco de macaco, Aguassu

CULTIVATION CONDITIONS

The crop requires a tropical climate, high temperature, plenty of sunshine, fertile soil and an adequate water supply. Q. martiana is best suited to a humid climate and is found in rainforest regions whilst Q. oleifera is found in drier, semi deciduous forests (Godin). Q. oleifera thrives under conditions sub-optimal for the cultivation of coconut (Godin), and appears to be restricted to the Sao Francisco River Basin in Minas Gerais, Brazil (Anderson).

MAJOR PRODUCING COUNTRIES

Babassu is widespread in Brazil, Mexico and Guyana. In Brazil alone it occupies an estimated area of 2-00 000 km which is concentrated in the states of Maranhao, Piaui and Gojas (May).

It is estimated that there are between 5 and 25 billion trees in Brazil (Ecky).

In 1980 Brazil harvested 254 000 tonnes of wild Babassu nuts (Bucher).

YIELD AND DESCRIPTION

The Babassu palm produces fruit in large bunches containing, on average, 200 individual fruits. However, bunches with up to 600 fruits do occur. The individual bunch weights range from 40-90 kg and the tree produces 1-4 bunches each year. Production starts at around 8 yrs old. (Anon). The individual fruits are 8-15 cm long and 5-9 cm broad and weigh 150200 g. Each contains 3-8 kernels with an oil content of 60-70% (1). The dry fruit is made up of 11-14% outer shell, 14-25% mesocarp, 50-67% woody inner shell and 610% kernels. (Peace). The outer fibrous portion of the fruit contains only about 1% oil (Ecky). Palms growing wild produce only 20 kg/ha compared to 1500 kg/ha in plantations. This is largely due to the greater tree density.

MAIN USES

In addition to its importance for the extraction of edible oil the Babassu palm can be used to make many products during its lifecycle. The leaves are used for thatch, basket work, construction and fodder, the trunks for bridges and building and the fruit for animal feed and charcoal (May). The palm is of considerable economic importance in rural Brazil and it is estimated that some 450 000 families collect and process Babassu.

II. AGRICULTURAL ASPECTS

CULTIVATION

Naturally growing forests are important ecologically as they possess a unique method of nutrient recycling which supports other forms of agriculture. While most palms grow in this way some plantations have been established in Brazil (Anderson).

The two species Q. martiana and Q. oleifera are often classed as different varieties.

HARVESTING PERIOD

In Brazil mature fruits begin to fall from their bunches between August and November and continue to drop until the rainy season begins in January and February.

When the tree is in flower all the year round it does not usually bear fruit.

Fruits lying on the ground at harvest are attacked by bruchid beetles (Pachymerus nucleanum) which enter the fruity and eat the kernels. After a period of three months some 70% of the fruits on the ground will have at least one kernel destroyed by the larvae. The larvae are known locally as "gongo" and are used for fish bait or fried for consumption (May).

HARVESTING METHODS

Harvesting occurs naturally, as the seeds ripen and mature they fall to the ground. They are then gathered by hand.

III. POST HARVEST TREATMENT, PRESERVATION AND STORAGE

PRE-TREATMENT

The nut is dried in the sun to facilitate the removal of the shell from the kernel. If protected from rain etc., babassu fruits can be stored without undergoing any signs of deterioration for some considerable time.

IV. PROCESSING

PROCESSING METHODS

The fruits have a hard thick shell (averaging 5cm in diameter) which is difficult to crack by machine. It is estimated that a pressure of approxi mately 1 tonne is needed to crack the shells open. While mechanical crackers have been developed their weight and power requirements have in general made them inappropriate for use in Babassu growing areas. As 1 tonne of nuts only yields 120 kg of kernels transportation of whole nuts to crackers has also proved impractical. In most areas the kernels are extracted locally by hand. The National Academy of Sciences estimates that this hand cracking accounts for 57% of the total processing cost. (Anon) It is important that the seeds are dried before decortication. If they have a high moisture content damage, occurring during the process, can initiate enzy matic activity and cause rancidity in the oil.

Decorticating is usually carried out at home although some women do remove the kernels in the forest. The fruit is placed on a hatchet blade or an axe and is hit with a wooden club until it splits. The broken pieces are in turn hit against the blade to dislodge the kernels. Most people can extract 3-5 kg kernels per day and a good worker can sometimes extract up to 10 kg.

A small proportion of the kernels extracted (0.7 kg per household during peak harvest period) is used domestically. The rest are sold immediately after cracking.

LOCAL PRODUCTS

The fruit's mesocarp can be ground into a meal for animal feed or human consumption.

The shells are suitable for fuel or can be made into charcoal. Husks are sometimes burnt in fields to protect crops against insect" or in some areas used to smoke rubber.

Local households produce charcoal on a weekly or biweekly basis. The husks are dried and then pushed gradually into a pit about 1m diameter and 1m deep.

They are burnt for one hour after which time water is sprinkled on them. After being left overnight they are collected and stored in baskets. An average household uses 25 kg charcoal per week for cooking May).

Babassu charcoal is also being increas ingly sold to national and foreign buyers for fuel use in industry.

OIL EXTRACTION

Oil is removed by hot water floatation or mechanical expression.

Hot Water: Kernels are lightly roasted and then mashed in a mortar. Water is added and the mixture boiled. The oil released rises to the surface and is skimmed off (May).

Expression: After grinding, oil can be extracted from the kernels in simple presses. On a larger scale conventional screw oil expellers are used .

The kernel yields 60-70% of an oil which is somewhat similar to coconut oil. It is colourless and does not readily become rancid. Refined oil can be used for margarine production and general food purposes. The crude oil is suitable for soap production and detergents. It is also used for burning in lamps.

MAJOR FATTY ACID CONPOSITION

(Source: Echy)

At tropical ambient temperatures the oil is completely liquid but in temperate climates it solidifies, having a consistency similar to petroleum jelly and becoming white in colour (Peace).

LOCAL PRODUCTS

Dried residues of the kernels are used in coastal areas by fisherman to make a fish bait (May).

The cake remaining after oil extraction is somewhat similar to coconut oil cake, and is used in cattle feed. However, the irregular supply of this material has meant that it only occasionally used in formulations at levels of 5-10. (Lennerts).

EQUIPMENT

Nut Crackers, stones, axes, clubs. Mortars and Mills. Cooking pots and ladles for floatation extraction, Presses and expellers. There is a lack of identifiable information for the following areas: AGRICULTURAL ASPECTS, planting period and major diseases; POST HARVEST, pretreatment; OIL EXTRACTION, nomenclature of products.

BIBLIOGRAPHY

ANON "Under Exploited Tropical Plants With Promising Economic Value", pp.89-93, National Academy of Sciences, 3rd Print, 1977.

ANDERSON, A.B. BALICK, M.J. "Taxonomy of the Babassu Complex (Orbignya spp. Palmae)", Systematic Botany, 13, I, 1988.

ANDERSON, A.B. "Management of Native Palm Forests: a Comparison of Case Studies in Indonesia and Brazil", From Agroforestry: Relatives, Possibilities and Potentials, Edited by Gholz, E. L. pp.155-167, Dordrecht Netherlands, 1987.

BERNARDINI E. "Oilseeds Oils and Fat", Volume II, Oil and Fat Processing", 2nd Edition, Interstampa, Rome, 1985.

BUCHER, H. "Useful Plants of Neotropical Origin and their Wild Relatives", pp.140-141, Springer-Verlag, 1989.

ECKY, E.W. "Palms and Other Monocotyledons", pp.358-361, "Vegetable Fats and Oils", Reinhold Publishing Corp, 1954.

GODIN, N.J. SPENSLEY, P.C. "Oils and Oilseeds", pp. 1-3, Crop and Product Digests No. 1, Tropical Products Institute, 1971.

GONICKE, F.V. REIMANN, M. "Fuel Instead of Food. How a Wrong Policy Alternative for Energy Increases Hunger", Reinbeck bei Hamburg, Germany, 1982.

LENNERTS, L. "Oilcakes and Oilmeals as Raw Materials for the Production of Mixed Feeds, 3, Babassu Cake and Babassu Oilmeal", Muhle and Mischfuttertechnik, 1988.

MAY, P.H. "A Modern Tragedy of the Non-Commons: Agro Industrial Change and Equity in Brazil's Babassu Palm Zone", Dissertation Series, Latin American Studies Program, Cornell University, 91, 1986.

MAY, P.H. ANDERSON, A.B. BALICK M.J. FRAZAO, J.M.F. Subsistence Benefit from the Babassu Palm (Orbignya martiana)", Economic Botany, 1985, 39, 2, 113-129.

PESCE, C. "Oil Palms and Other Oilseeds of the Amazon", pp.75-88, Reference Publications Incorporated, 1985.

PURSEGLOVE, J.W. "Tropical Crops: Monocotyledons", Longman, 1985.

VAUGHAN, J.G. "The Structure and Utilisation of Oil Seeds", Chapman and Hall, 1976.

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