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fractionation of palm oil

Palm oil

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Palm oil from Ghana with its natural dark color visible, 2 litres
Palm oil from Ghana with its natural dark color visible, 2 litres
Palm oil block showing the lighter color that results from boiling.
Palm oil block showing the lighter color that results from boiling.

Palm oil is a form of edible vegetable oil obtained from the fruit of the oil palm tree. Previously the second-most widely produced edible oil, after soybean oil, 28 million metric tons were produced worldwide in 2004[1]. It may have now surpassed soybean oil as the most widely produced vegetable oil in the world.[2]

The palm fruit is the source of both palm oil (extracted from palm fruit) and palm kernel oil (extracted from the fruit seeds). Palm oil itself is reddish because it contains a high amount of betacarotene. It is used as cooking oil, to make margarine and is a component of many processed foods. Boiling it for a few minutes destroys the carotenoids and the oil becomes white.

Palm oil is one of the few vegetable oils relatively high in saturated fats (such as coconut oil) and thus semi-solid at room temperature.

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[edit] History

Palm oil (from the African Oil Palm, Elaeis guineensis) was long recognized in West African countries, and among West African peoples it is in widespread use as a cooking oil. European merchants trading with West Africa occasionally purchased palm oil for use in Europe, but as the oil was bulky and cheap, and due to the much higher profits available from slave-trading, palm oil remained rare outside West Africa. During the early nineteenth century, the decline of the Atlantic slave trade and Europe's demand for legitimate commerce (trade in material goods rather than human lives) obliged African and European countries to seek new sources of trade revenue. In the Asante Confederacy, state-owned slaves built large plantations of oil palm trees, while in the neighbouring Kingdom of Dahomey, King Ghezo passed a law in 1856 forbidding his subjects from cutting down oil palms. Palm oil became a highly sought-after commodity by British traders, the oil being used as industrial lubricant for the machines of Britain's ongoing Industrial Revolution, as well as forming the basis for various brands of soap such as Palmolive. By c.1870, palm oil constituted the primary export of some West African countries such as Ghana and Nigeria. By the 1880s, cocoa had become more highly sought-after, leading to the decline of the palm oil industry and trade within these countries.

Palm oil was introduced in Malaysia (then Malaya) in 1917 when the first plantation was established. Then the oil palms plantation was mostly operated by English landowners. From the 1960's major oil palm plantation scheme was introduced by the government mainly to eradicate poverty. Each settlers are allocated 10 acres of land (about 4 hectares) planted either with oil palm or rubber, and they are given 20 years to pay off the land.

In 2004, Malaysia produces 14 million tons of palm oil from more than 38,000 square kilometres of land, making it the largest exporter of palm oil in the world.

[edit] Chemical composition

Palm oil and palm kernel oil are composed of fatty acids, esterified with glycerol just like any ordinary fat. Both are high in saturated fatty acids, about 50% and 80%, respectively. The oil palm gives its name to the 16 carbon saturated fatty acid palmitic acid found in palm oil; monounsaturated oleic acid is also a constituent of palm oil while palm kernel oil contains mainly lauric acid. Palm oil is the largest natural source of tocotrienol, part of the vitamin E family. Palm oil is also high in vitamin K and dietary magnesium.

Napalm derives its name from naphthenic acid, palmitic acid and pyrotechnics or simply from a recipe using naphtha and palm oil.

The approximate concentration of fatty acids (FAs) in palm oil is as follows:[3]

Fatty acid content of palm oil
Type of fatty acid

pct
Palmitic C16
 
 44.3%
Stearic C18
 
 4.6%
Myristic C14
 
 1.0%
Oleic C18
 
 38.7%
Linoleic C18
 
 10.5%
Other/Unknown
 
 0.9%
green: Saturated; blue: Mono unsaturated; orange: Poly unsaturated


Fatty acid content of palm kernel oil
Type of fatty acid

pct
Lauric C12
 
 48.2%
Myristic C14
 
 16.2%
Palmitic C16
 
 8.4%
Capric C10
 
 3.4%
Caprylic C8
 
 3.3%
Stearic C18
 
 2.5%
Oleic C18
 
 15.3%
Linoleic C18
 
 2.3%
Other/Unknown
 
 0.4%
green: Saturated; blue: Mono unsaturated; orange: Poly unsaturated


Fatty acids are saturated and unsaturated aliphatic carboxylic acids with carbon chain length in the range of C6 up to C24. An example of a fatty acid is palmitic acid

CH3 – (CH2)14 – COOH

Splitting oils and fats produces the fatty acids. Glycerin is produced as by-product. The split fatty acid is a mixture of fatty acids ranging from C6 to C18 depending on the type of Oil / Fat. The pure fatty acid is used as an important raw material in the manufacture of soaps, washing powder and other personal care products:[4] . It is important to purify the fatty acid to as high a product as possible.

[edit] Environmental and cultural impact

Palm oil nursery
Palm oil nursery

As of 2006, the cumulative land area of palm oil plantations is approximately 11 million hectares.[5] Demand for palm oil has been rising and is expected to climb further, particularly for use in biodiesel (see below). Rising demand may result in more tropical forest being cleared to establish new palm plantations. The is growing concern that this will be harmful to the environment in several ways:

  • Many places that are of interest for growing palm are biodiversity hotspots, increasing the impact of this development on the environment.[7] In addition to environmental impact, the logging and land-clearing by large timber companies that accompany the establishment of palm plantations threatens the livelihood of minority tribes such as the Penan and Iban in Sarawak, Borneo.[8]


A report released by Greenpeace on November 8, 2007, detailed the role played by growing demand for palm oil in Indonesian peat forest destruction and global warming. According to the report, many companies, including ADM, Unilever, Cargill, Proctor & Gamble, Dove soap, Nestle, Kraft and Burger King are driving the demand for palm oil used in food and cosmetics products such as Pringles, KitKat, Oreo cookies and Phildelphia cream cheese.

The Indonesian peatlands, unique tropical forests whose dense soil can be burned to produce energy, are being destroyed to make way for palm oil plantations. They are some of the world's great carbon sinks, and their destruction already accounts for four percent of annual global emissions.

The Greenpeace report, "Cooking the Climate," shows how companies are driving peatland destruction in the Indonesian province of Riau on the island of Sumatra, home to 25 percent of the country's palm oil plantations. There are plans to expand the area under concession by more than 11,000 square miles, which would deforest half of the province. This would have devastating consequences for Riau's peatlands, which have already been degraded by industrial development and store a massive 14.6 billion tons of carbon, roughly one year's greenhouse gas emissions.

Research conducted by Greenpeace through its Forest Defenders Camp in Riau documents how a major Indonesian palm oil producer is engaging in the large-scale, illegal destruction of peatland in flagrant violation of an Indonesian presidential order, as well as national forestry regulations. Palm oil from peatland is fed into the supply chain for global brands. Major multinational companies are all named in the report for turning a blind eye to peatland destruction for cheap vegetable oil.

The report also exposes the reality behind palm oil's use as a "biofuel." according to the report, replacing forests and peatlands with palm oil plantations relases more carbon dioxide than is saved by burning biofuels in place of diesel.

The full report can be found at: [Http://www.greenpeace.org/cookingtheclimate.]

[edit] Palm Oil as Biodiesel

Palm oil, like other vegetable oils, can be used to create biodiesel for internal combustion engines.

Biodiesel has been promoted as a form of biomass that can reduce net emissions of carbon dioxide into the atmosphere. Therefore, until recently it was viewed as a way to decrease the impact of the greenhouse effect and as a way of diversifying energy supplies to assist national energy security plans.

However, recent thinking has suggested that biofuels may not be a very effective counter to global warming[9]. The benefits to be gained from this type of biomass are partly negated when ancient forest is cleared to make room for oil palm[10][11]. Although palm oil has a comparatively high yield, the many problems linked to oil palm cultivation have encouraged research into alternative vegetable fuel oil sources with less potential for environmental damage, such as jatropha[12].

However, regardless of these new innovations, biodiesel production from palm oil is still in demand globally and will continue to increase. As such, new developments have been started in a number of countries around the world:

[edit] Malaysia

As a major producer of palm oil, the Malaysian government is also encouraging the production of biodiesel and the building of biodiesel plants that use palm oil. The plants will start operating from the middle of 2008 with a capacity of 100,000 tonnes of biodiesel annually. Strong demand for biodiesel from Europe, Colombia, India, South Korea and Turkey has fueled the industry's growth as more countries seek to augment their reliance on fossil fuels with 'greener' biofuel.

Malaysia has already begun preparations to change from diesel to bio-fuels by 2008, including drafting legislation that will make the switch mandatory. From 2007, all diesel sold in Malaysia must contain 5% palm oil. Being the world's largest producer of crude palm oil, Malaysia intends to take advantage of the rush to find cleaner fuels.

[edit] Indonesia

Growers in Indonesia are also increasing production of palm oil to meet the global demand spurred by biofuels, with the government looking for it to become the world's top producer of palm oil. However, fresh land clearances, especially in Borneo, are contentious for their environmental impact[13]. NGOs are now warning that, despite thousands of square kilometres of land standing unplanted in Indonesia, tropical hardwood forest are being cleared for palm oil plantations. Furthermore, as the remaining unprotected lowland forest dwindles, developers are looking to plant peat swamp land, using drainage that unlocks the carbon held in their trees and begins an oxidation process of the peat which can release 5,000 to 10,000 years worth of stored carbon. Drained peat is also at very high risk of forest fire, and there is a clear record of fire being used to clear vegetation for palm oil development in Indonesia.

[edit] Australia

On 23 Nov 2006 Australia's first palm oil based biodiesel plant was opened in Darwin. When fully operational in 2007 this plant should produce 140 million litres of biodiesel annually.[14]

[edit] Health

Palm oil, despite being the most used vegetable oil for cooking [15] (primarily because of its huge use in industrial food preparations), is one of the most unhealthy cooking oils available (after Coconut oil) [16][17][18]. Besides via the references, this information can also be derived from the table found at the cooking oil article, which gives the percentage of saturated, monounsaturated and polyunsaturated fatty acids.

Their heavy use nonetheless in the commercial food industry can thus only be explained by its comparatively low price, being one of the cheapest vegetable or cooking oils on the market [19]. Given the unhealthiness as a cooking oil, consumers are best to avoid it and use an alternative, more healthy, cooking oil as canola oil, soy oil, ... (see also: Cooking_oil). This should be done when they either prepare the food themselves or when they buy prepared foods. The latter however may not be simple as palm oil is described on food labels simply as "vegetable oil", instead of "palm oil". So it is advised that if the oil type is not specified, foods low (<5%>

Red palm oil, when compared to regular palm oil however, has been found to be more healthy. This is a result of several mitigating substances found in the red palm oil which slightly mitigate the burdon of its saturated fats; also found in the red palm oil. These compounds are:

[edit] Palm oil and the blood cholesterol controversy

For many years now, it has been established that the primary cholesterol-elevating fatty acids are the saturated fatty acids with 12 (lauric acid), 14 (myristic acid) and 16 (palmitic acid) carbon atoms with a concomitant increase in the risk of coronary heart disease. Monounsaturated fatty acids such as oleic acid is as effective in reducing serum total and low-density lipoprotein (LDL) cholesterol levels as polyunsaturated fatty acids such as alpha-linoleic acid.[24] The World Health Organization in its report[25] states there is convincing evidence that palmitic oil consumption contributes to an increased risk of developing cardiovascular diseases. Research in the US and Europe support the WHO report.

In a response to the report, the Malaysian Palm Oil Promotion Council cited a study in China comparing palm, soybean, peanut oils and lard (all of which contain saturated fat) showing that palm oil increased the levels of good cholesterol and reduced the levels of bad cholesterol in the blood (Dr. Koh Chu-Sing, Malaysian Palm Oil Promotion Council, citing Zhang, et al, 1995, 1997, 2006).[26]

An older study by Hornstra in 1990 also supported the claims of the Malaysian Palm Oil Promotion Council.[27]

A study by the Departments of Agricultural, Food and Nutritional Science and Medicine, University of Alberta showed palmitic acid to have no hypercholesterolaemic effect if intake of linoleic acid was greater than 4.5% of energy, but that if the diet contained trans fatty acids, LDL cholesterol increases and HDL cholesterol decreases. [28]

The studies supporting the Malaysian Palm Oil Promotion Council only addressed the issue of the effect of palm oil on blood cholesterol levels and not its total effect regarding cardiovascular diseases.

[edit] See also

[edit] References

  1. ^ United States Department of Agriculture, Agricultural Statistics 2004. Table 3-51.
  2. ^ Malaysian Oil Palm Statistics 2005. Malaysian Palm Oil Board.
  3. ^ Ang, Catharina Y. W., KeShun Liu, and Yao-Wen Huang, eds. (1999). Asian Foods
  4. ^ Faessler, Kolmetz, (2004). Advanced Fractionation for the Oleo Chemcial Industry Oil and Fat Conference
  5. ^ Palm oil plantations already estimated at occupying 11 million hectares. Panda.org. Retrieved on 2007-09-29.
  6. ^ Helen Buckland. The Oil for Ape Scandal: How Palm Oil is Threatening the Orang-utan. Friends of the Earth. Retrieved on 2007-09-29.
  7. ^ Palm oil threathening endangered species.
  8. ^ "Malaysia says activists trying to harm palm oil industry by highlighting orangutan woes", International Herald Tribune, April 16, 2007.
  9. ^ Greenpeace FAQ: Palm oil, forests and climate change
  10. ^ International Herald Tribune UN negative on biofuels
  11. ^ IPCC's Mitigation of Climate Change report negative on biofuels
  12. ^ The Times Jatropha as a less environmental-damaging replacement candidate for biofuel production
  13. ^ Palm oil warning for Indonesia
  14. ^ Australian Natural Fuel refiner's website
  15. ^ Palm oil being one of the most used cooking oils
  16. ^ [http://www.cspinet.org/palm/ Palm oil promoting heart disease
  17. ^ Solid, hydrogenated oils least healthy oils
  18. ^ Oils with high saturated content (palm, coconut oil) least healthy oils
  19. ^ Palm oil one of the cheapest vegetable oils on the market (NOTHING at this link supports this assertion - it's an assertion that burning palm oil causes global warming.)
  20. ^ [DOI:10.1002/ejlt.200600264]
  21. ^ (citation T15 in)Vitamin A and the Common Agenda for Micronutrients
  22. ^ db=PubMed&cmd=Retrieve&list_uids=12891825 'Red palm oil supplementation: a feasible diet-based approach to improve the vitamin A status of pregnant women and their infants.'
  23. ^ Radhika MS, Bhaskaram P, Balakrishna N, Ramalakshmi BA., Red palm oil supplementation: a feasible diet-based approach to improve the vitamin A status of pregnant women and their infants., [[{{{publisher}}}]], [[{{{date}}}]].
  24. ^ Vessby,B.1994. INFORM 5(2):182-185.
  25. ^ Diet, Nutrition and the Prevention of Chronic Diseases (WHO Technical Report Series 916. Geneva. 2003. pages 82, 88 &c)
  26. ^ Koh, C.S. 2006. Comments On Draft Document: Diet, Nutrition, and the Prevention of Chronic Diseases. http://www.who.int/dietphysicalactivity/media/en/gsfao_cmo_068.pdf
  27. ^ Hornstra, 1990 `Effects of dietary lipids on some aspects of the cardiovascular risk profile'. In G. Ziant [ed.], LIPIDS AND HEALTH.
  28. ^ Cholesterolaemic effect of palmitic acid in relation to other dietary fatty acids

[edit] Social and environmental palm oil links

[edit] Other palm oil links

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