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By: Don Cobb
Published: 2001/07/20


Perennials that year after year incorporate atmospheric carbon dioxide into biomass, improve our environment, and give us useful food, feed and fuel are wonderful plants. Residents of West Africa have long recognized the African oil palm (Elaeis guineensis) as such a plant. There may be places where this is an underutilized resource, and other places where it could be grown but is not known.

Alvaro Ocampo Duran has suggested that the African oil palm is a strategic resource for integrated systems of tropical production, ranging from a small farmer with a completely integrated system to a large commercial production system. In the latter case, the integration of other crops and livestock could help curb pollution and enhance biodiversity. Our primary interest is in finding ways the African oil palm can be used by small farmers who have not previously grown it. Quality of life could be improved, whether a family has a few trees to supply themselves with a source of cooking oil or whether larger plantings are established and integrated with other crops and with animal production.

Nutritional Value of Crude Red Palm Oil

Crude red palm oil, locally extracted, can have a significant positive impact on the nutritional status of populations where it is produced. It is a good source of carotenoids that can be transformed into vitamin A, and byproducts from the pressing can be important ingredients in pig feed. Most of the commercial palm oil on the world market contains almost no carotenoids, as they are destroyed in processing. Malaysia, now recognizing the value of the carotenoids, has developed a special process to produce a deodorized and deacidified red palm oil which is also a good source of vitamin A. The carotenoids are also separated and sold in various forms as health promoters.

According to an article in a recent issue of SIGHT & LIFE (Newsletter 2/1999), red palm oil is the richest natural plant source of carotenoids (500-700 ppm). Of these, 56% are Beta-carotene—the carotenoid most easily converted to vitamin A. Thus as little as one teaspoon of red palm oil per day is sufficient to meet the vitamin A requirements of a child.

Various studies have shown that the carotenoids in red palmoil are bioavailable (i.e. they can be used by the body) and are comparable to synthetic vitamin A. This is significant because more and more scientific results point to a low bioavailablity of Beta-carotene from vegetables, especially when eaten raw, steamed or cooked with no fat (Newsletter 3/99). In addition to their ready conversion to vitamin A, the carotenoids are antioxidants. They help to minimize or prevent oxidation and thus reduce the incidence of diseases in which free radicals are implicated.

Various studies have shown that the carotenoids in red palm oil are bioavailable (i.e. they can be used by the body) and are comparable to synthetic vitamin A. This is significant because more and more scientific results point to a low bioavailablity of Beta-carotene from vegetables, especially when eaten raw, steamed or cooked with no fat (Newsletter 3/99). In addition to their ready conversion to vitamin A, the carotenoids are antioxidants. They help to minimize or prevent oxidation and thus reduce the incidence of diseases in which free radicals are implicated.

Studies conducted in the 1980’s helped us to understand that consumption of dark green leaves and yellow fruits could protect against the severe vitamin A deficiency that leads to blindness. However, the studies also showed that such consumption might not be capable of preventing a symptomless vitamin A deficiency in a substantial proportion of the children in developing countries. There is evidence that this symptomless vitamin A deficiency, when linked with poor general nutrition, can lead to a significant increase in the risk of illness and death in young children. (SIGHT & LIFE Manual on Vitamin A Deficiency Disorders, 2001).

Vitamin A is a fat-soluble vitamin that is stored in the liver. Therefore, the liver of animals is a concentrated source of vitamin A and should be eaten only infrequently by most people. If we consume too much it can be toxic. Yet multitudes of children suffer from vitamin A deficiency. Their diets do not contain enough vitamin A to supply their needs, let alone build up a surplus. One thing in their favor is that where the intake of vitamin A is low, the body seems to more efficiently use what it does take in. Hence small amounts of red palm oil (or fish liver, butter, whole milk, eggs & cheese, which also supply vitamin A) could keep many from suffering from night blindness (or total blindness) and the many other health complications suffered by those with an inadequate intake of Vitamin A. In many parts of the tropics where dairy products would be difficult to find, the oil palm can be grown.

Red palm oil is easily digested, absorbed and utilized. In areas where it is widely used it plays a useful role in meeting energy and essential fatty acid needs. It has been a safe and nutritious source of edible oil for healthy humans for thousands of years in West Africa where the plant is believed to have originated. It contains no cholesterol. Because it has a moderate level of saturated fatty acids, it does not need to be artificially hydrogenated (an industrial process that turns a liquid fat into a solid fat like margarine) for use as a fat component in foods. As a result it does not contain the exceptionally harmful trans-fatty acids that are created when oils are hydrogenated.

While too much oil or fat in the diet can be detrimental, too little can also lead to serious problems. Fat is required to help absorb not only vitamins but also protein and other nutrients. Poor nutrition is sometimes linked to a lack of fat in people’s diets.

Oil palm is the highest-yielding vegetable oil crop in the world. It produces several types of oil that can be used for cooking, margarine, soap and various industrial uses. At the village level, it has long been a source of energy and income in areas where the oil palm is indigenous.

If red palm oil could eliminate the problem of vitamin A deficiency (that can cause blindness and many other complications), and if the plant is one of the world’s most efficient oil producers, why isn’t it grown in more parts of the tropical world? There are actually quite good reasons, but some of the obstacles are being overcome.

Some Environmental Limitations and How They Are Overcome

Only limited areas meet the climatic requirements of oil palm. The best locations are found within 10 degrees of the Equator, although it is commercially grown up to 17 degrees from the Equator and is sometimes found even further north or south. It likes a rainfall in excess of 1500 mm (60 in) with a fairly even distribution throughout the year. While this is the ideal, it has performed well in some areas with a marked dry season and on a wide variety of soils.

The ideal temperature range for oil palm is between 22-32°C (72-90°F). New hybrids developed by FAO and a Costa Rican company have been successfully grown above 900 m in Ethiopia and these are being further tested in Malawi, Zambia and Cameroon, so there is reason to believe that its growing range can be expanded.

It can take up to two years for oil palm seeds to germinate. Oil palm plantations use special heating equipment and laboratory methods to get quick (3-4 months), even germination. For the person serious about getting started with oil palm we repeat the following information that we excerpted from Africa Link Newsletter No. 19 in EDN 68-6. Bob Mann, with the Methodist Relief & Development Fund, shared a compost pit method (used by PRTC Mfonta nursery) for achieving better germination.

A pit is first dug about one foot deep. The bottom is lined with male inflorescences from the oil palm. A layer of ripe oil palm fruits (taken from the inside layers of the fruit bunch) is put down. This is covered with a thin layer of grass, then a layer of soil, and finally with banana stems to prevent chickens from scratching the contents out. The ‘compost’ germination pit is watered lightly to keep it moist and to encourage the contents to heat up. In five to six months the pit contents are opened. By this point there should be the start of good germination. Seeds that have sprouted (with growing shoots up to 2.5 cm (1 in) in length) are planted in prepared polybags or pots that are 30 cm (12 in) in height and 18 cm (7 in) in diameter.

Shading should be provided for younger seedlings. As they grow they can be exposed to more direct sunlight. They usually remain in the nursery for about one year. They will benefit from six to eight weekly applications of a compound fertilizer (1:1:1 ratio) with added magnesium, placed no closer than 10 cm (4 in) from the plant. Phosphorus is worked into the soil before the plants are transplanted to the field. After planting, N and K are added at six monthly intervals around the plants. For the village ‘organic’ farmer these nutrients can be supplied in other forms–manure, compost or mulch and a good cover crop (Centrosema or Pueraria).

For general purposes three types of oil palm fruit are recognized. Wild or semi-wild groves in West Africa are ‘dura’ and have a thick shell. Oil yield is low and they take longer to begin to bear fruit. When the ‘dura’ is crossed with ‘pisifera’ (which has no shell) a hybrid is produced (‘tenera’) which has a shell of medium thickness. It is a good oil producer and begins to bear sooner. Dura, pisifera, and the cross known as tenera all belong to the Eleaeis guineensis species.

‘Tenera’ palms will probably begin to bear fruit three to four years after they have been planted in the field. The best yields come after an additional four to five years. The trees will bear fruit for 30 years or more, although it becomes difficult to harvest the fruit bunches when the trees become very tall.

We have noted the disadvantages of the dura oil palms: lower yields and a longer period of growth before coming into production. However, they may still have a place for the resource-poor farmer. Hybrid seed does not have to be purchased. Dura palms do not have to be fertilized as do the hybrids. Some say they yield more than tenera when tenera is not fertilized. Others say tenera will yield more even if it is not fertilized. It probably depends on the soil and the care.

Adequate pollination in areas devoid of natural pollinators can be achieved by applying collected pollen by hand or by introducing a weevil (Elaedobius kamerunicus) which is specific to oil palm. Because seed is available all year and is one of the easiest to ship it should not be so difficult to find the seed you would need to get started. ECHO does not have oil palm seed in its seedbank, but if you live and work in a part of the world where the oil palm grows, seed should be available. Paul Noren, a Covenant Agricultural Missionary from the Central African Republic/Democratic Republic of the Congo who recently spent some time at ECHO as “Missionary in Residence,” said that if seed or seedlings were obtained from a tenera plantation about 50% would be tenera, 25% dura, and 25% pisifera. Where hybrid seed cannot be obtained, this would give a reasonable option.

In southern Benin, where they have attempted to move toward hybrid production, there are still viable examples of the ‘palmeraie jardin’ (‘oil palm forest’) or ‘palmeraie naturelle’ (‘natural oil palm system’). Here the dura plantations cover about 40,000 hectares and have adapted to the dry conditions (1200 mm in a good year). Palm density is said to vary greatly. One will find palms of different ages inter-planted with annual food crops when a lower density is used. When there are no annual crops in the field, the land beneath the trees lies fallow. The palm trees protect the soil from erosion and improve the soil’s natural fertility with the help of superficial roots that retain nutrients. This system at best produces about half of what could be obtained from a tenera plantation, but it does so at no cost to the farming family except their labor.

Processing Palm Nuts

It begins with the separation of the fruit from the bunch (regime). Bunches are said to be ready when the first fruits drop from them. In many places the bunches are placed in small mounds, covered and allowed to ferment for a few days in order to facilitate the removal of the fruit from the regime. Studies in Nigeria (Indigenous Knowledge and Development Monitor, Vol. 8, Issue 1 March 2000) show that the best quality and highest quantity of crude red palm oil is obtained when the fruit ferments for no more than three days before further processing.

Figure 1: In the Democratic Republic of the Congo, metal barrels are adapted to simplify the extraction of crude red palm oil from pre-boiled, hot palm fruits. Metal arms from the central shaft release the oil from the fruit. Photo courtesy of Paul Noren.

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The next stage of processing, the hot part, involves boiling the fruits and pounding them to separate the flesh from the kernels. This also kills the enzymes that would turn some of the oil into “fatty acids.” After pounding, the oil is separated from the flesh in different ways; by hand pressing, by mixing with water and allowing oil to float to the surface, or by using a manual press to extract the oil. Village level processing separates about half of the oil from the fruits. Local processes vary in the percentage of oil obtained and in the quality of oil. If the fruits are allowed to ferment for too long or are handled roughly before boiling, the level of free fatty acids will be higher and the oil will be of a lower quality.

Red palm oil has a deep orange-red color, a strong aroma, and a highly viscous nature. From my perspective it is an easily acquired taste. Others might find it more difficult to add red palm oil to their diets. Due to its health promoting properties some nutritionists in India, not a traditional oil palm area, have been trying to find ways to incorporate red palm oil into their dietary traditions.

Additional Products and Uses

In addition to oil, the plant produces many other useful products. After the crude red oil is removed from the fleshy pulp the latter can be strained and boiled down to a thick sauce. This is used to produce many tasty West African dishes. Two by-products of oil production are the oil impregnated fiber recovered when the oil is filtered off and the ‘mud’ that remains after the oil has been clarified and centrifuged. In the factory this residue is often reprocessed to remove more of the oil. In village processing the oilimpregnated fiber and ‘mud’ remain together and have a higher content of oil. This oil-rich mix can be a complete replacement for cereal grain in the diet of the growingfinishing pig. All that is needed is 200 gm of a good protein supplement per day and a 20 kg pig can grow to 90 kg in 135 days (Thomas R. Preston and Enrique Murgueitio in Strategy for Sustainable Livestock Production in the Tropics)

. We should also note that raw palm oil can be used as an energy source for pigs and for ducks that have access to water for cleaning. Chickens can also use it, but look rather frightening after they have eaten the oil. Perhaps it could be mixed with a carrier feed to make it a bit less messy. Whole fresh fruit can also be the energy feed resource for growing finishing pigs. They will eat the fibrous material surrounding the kernel and then they will crack and extract the kernel from the nuts. Rice polishings, or some other available protein supplement, should be given at the rate of 200 grams per day during the growing and 250 grams during the finishing phase. To be able to take a weaner pig to market weight on fresh palm fruit and perhaps only one 60 kg bag of protein supplement, or even on rice polishings, is definitely an example of a good alternative system (Rena Perez, Feeding Pigs in the Tropics, FAO Animal Production Health Paper #132).

Conclusion

Oil palms need special growing conditions—but not so special as we once believed. It takes a long time to germinate the seeds—but it can be done with village technology. The trees will not produce for three to four years—but they will continue to produce for more than 30 years. Processing the oil is labor intensive—but there are many people who need jobs. It is a plant that is being used to make money for large scale investors in Malaysia, Indonesia and elsewhere. Perhaps the village level technology with oil palm developed in West Africa (and being further developed in Colombia) deserves to be spread to other parts of the world where the growing conditions for oil palm exist.

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Cite as:

Cobb, D. 2001. Red Palm Oil: More Than Just a Good Source of Vitamin A. ECHO Development Notes no. 72