Wednesday, January 26, 2011

Coconut oil | Fatty acid content of coconut oil | coconut oil Centrifuge Process

Coconut oil is extracted from the kernel or meat of matured coconut harvested from the coconut palm (Cocos nucifera). Throughout the tropical world it has provided the primary source of fat in the diets of millions of people for generations. It has various applications in food, medicine, and industry. Coconut oil is very heat stable so it makes an excellent cooking and frying oil. It has a smoke point of about 360 °F (180 °C). Because of its stability it is slow to oxidize and thus resistant to rancidity, lasting up to two years due to high saturated fat content.[1]

Fatty acid content of coconut oil
Type of fatty acid

pct
Lauric saturated C12
47.5%
Myristic saturated C14
18.1%
Palmitic saturated C16
8.8%
Caprylic saturated C8
7.8%
Capric saturated C10
6.7%
Stearic saturated C18
2.6%
Caproic saturated C6
0.5%
Oleic monounsaturated C18
6.2%
Linoleic polyunsaturated C18
1.6%
Coconut oil contains approximately 92.1% saturated fatty acids, 6.2% monounsaturated fatty acids, 1.6% polyunsaturated fatty acids. The above numbers are averages based on samples taken. Numbers can vary slightly depending on age of the coconut, growing conditions, and variety.

red: Saturated; orange: Monounsaturated; blue: Polyunsaturated

Contents

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[edit] Production

In the wet process, coconut milk is made first and then the oil is extracted from the milk. Coconut kernel is shredded and mixed with water. Then it is pressed and the oil is extracted. The resulting oil/water mixture is left to sit and it separates into two layers, watery on the bottom, creamy on top. The thicker cream is decanted off the top and the original method of separation involved heating or fermenting the milk to separate the oil.[2] This traditional method made a very unstable oil with a short shelf life meant for quick daily use. Due to its miscible nature coconut oil cannot be separated naturally from the cream. All high volume modern methods incorporate heating, fermentation, and or centrifugal force to separate the oil from the water. Some minor heating is generally done afterwards (often in a low temperature vacuum chamber) to drive off excess moisture and produce a more purified product and to extend shelf life. Proper harvesting of the coconut (the age of a coconut can be 2 to 20 months when picked; the time of harvesting makes a significant difference in the effiacy of the oil making process) and the use of a centrifuge process make the best final extracted product. Any coconut oil made from a non-copra style of extraction can be called virgin organic coconut oil but only the centrifuge process can make raw oil. When done properly it doesn't need to be heated or fermented to remove moisture.[3]

In the dry process the oil is extracted directly from the kernel. The coconut kernel is first shredded and dried in an oven to about 10 to 12% moisture. The dried, shredded coconut is then placed into a press and the virgin oil is expelled.[4]

The Asian and Pacific Coconut Community (APCC), whose 18 members produce about 85% of the coconut sold commercially,[5] has published its Standards for Virgin Coconut Oil.[6] The Philippines has established a Department of Science and Technology (DOST) governmental standard.[7]

The USDA has published historical production figures for coconut oil for years beginning October 1 and ending September 30:[8]

Year 2005–06 2006–07 2007–08 2008–09
Production, Million Tonne 3.46 3.22 3.53 3.33

[edit] Centrifuge Process 1

Once the coconut milk has been harvested and fermented, [9] the fermented coconut milk is centrifuged to separate the oil from the water and solids. The end result is an oil that is ~.10-.15% moisture.

[edit] Centrifuge Process 2

The Cold Centrifuge Series(™)[10] uses specific type of coconut (Java Tall), which are picked at a specific time to improve the quality, output and ease of oil production. A wet/cold press process is used to create the coconut milk that is then put through the centrifuge process. Temperature and centrifuge time are also key components in the creation of this virgin oil and from beginning to end there is no heat involved in the process to remove moisture.

[edit] RBD

Coconuts sundried in Kozhikode, Kerala for making copra, which is used for making coconut oil
Coconut Oil expelled from Copra at an oil mill in Tripunithura, Kerala, India

RBD stands for "refined, bleached, and deodorized." RBD oil is usually made from copra (dried coconut kernel). Copra can be made by smoke drying, sun drying, or kiln drying. The dried copra is then placed in a powerful hydraulic press with added heat and the oil is extracted. This yields up practically all the oil present, amounting to more than 60% of the dry weight of the coconut.[11]

This "crude" coconut oil is not suitable for consumption because it contains contaminants and must be refined with further heating and filtering. Another method for extraction of a "high quality" coconut oil involves the enzymatic action of alpha-amylase, polygalacturonases and proteases on diluted coconut paste.[12]

Unlike virgin coconut oil, refined coconut oil has no coconut taste or aroma. RBD oil is used for home cooking, commercial food processing, and cosmetic, industrial, and pharmaceutical purposes.

[edit] Hydrogenation

RBD coconut oil can be processed further into partially or fully hydrogenated oil to increase its melting point. Since virgin and RBD coconut oils melt at 76 °F (24 °C), foods containing coconut oil tend to melt in warm climates. A higher melting point is desirable in these warm climates so the oil is hydrogenated. The melting point of hydrogenated coconut oil is 97–104 °F (36–40 °C).

In the process of hydrogenation, unsaturated fats (monounsaturated and polyunsaturated fatty acids) are combined with hydrogen in a catalytic process to make them more saturated. Coconut oil contains only 6% monounsaturated and 2% polyunsaturated fatty acids. In this process some of these are transformed into trans fatty acids.

[edit] Fractionation

Fractionated coconut oil is a fraction of the whole oil, in which the long-chain fatty acids are removed so that only medium chain saturated fatty acids remain. Lauric acid, a 12 carbon chain fatty acid, is often removed as well because of its high value for industrial and medical purposes. Fractionated coconut oil may also be referred to as caprylic/capric triglyceride oil or medium chain triglyceride (MCT) oil because it is primarily the medium chain caprylic (8 carbons) and capric (10 carbons) acids that make up the bulk of the oil.

MCT oil is most frequently used for medical applications and special diets.

[edit] Uses

[edit] Culinary arts

Coconut oil is commonly used in cooking, especially when frying. In communities where coconut oil is widely used in cooking, the unrefined oil is the one most commonly used. Coconut oil is commonly used to flavor many South Asian curries. Relative to other cooking oils, it creates minimal harmful byproducts when heated.[13]

Contrary to many Internet sources,[who?] the caloric content of coconut oil is very nearly the same as that of other dietary fats, being reduced only slightly by the presence of medium chain triglycerides which constitute less than half of the total fat content. A value of 8.3 kcal/g has been quoted for dietary medium-chain triglycerides.[2]

Hydrogenated or partially hydrogenated coconut oil is often used in non-dairy creamers, and snack foods including popcorn.[14]

Hydrogenated coconut oil is also sold in Australia under the brand-name Copha and is the main ingredient in Australian snacks such as Chocolate crackles and White Christmas.

[edit] Industry

[edit] Engine feedstock

Coconut oil has been tested for use as a feedstock for biodiesel to be used as a diesel engine fuel. In this manner it can be applied to power generators and transport using diesel engines. Since straight coconut oil has a high gelling temperature (22–25 °C), a high viscosity, and a minimum combustion chamber temperature of 500 °C (932 °F) (to avoid polymerization of the fuel), coconut oil is typically transesterified to make biodiesel. Use of B100 (100% biodiesel) is only possible in temperate climates as the gel point is approximately 10 °C (50 °F). The oil needs to meet the Weihenstephan standard[15] for pure vegetable oil used as a fuel otherwise moderate to severe damage from carbonisation and clogging will occur in an unmodified engine.

The Philippines, Vanuatu, Samoa, and several other tropical island countries are using coconut oil as an alternative fuel source to run automobiles, trucks, and buses, and to power generators.[16] Coconut oil is currently used as a fuel for transport in the Philippines.[17] Further research into the oil's potential as a fuel for electricity generation is being carried out in the islands of the Pacific.[18][19] In the 1990s Bougainville conflict, islanders cut off from supplies due to a blockade used it to fuel their vehicles.[20]

[edit] Engine lubricant

Coconut oil has been tested for use as an engine lubricant; the producer claims the oil reduces fuel consumption and smoke emissions, and allows the engine to run at a cooler temperature.[21]

[edit] Transformer oil

Transformer oil acts as an insulating and cooling medium in transformers. The insulating oil fills up pores in fibrous insulation and also the gaps between the coil conductors and the spacing between the siding and the tank, and thus increases the dielectric strength of the insulation. A transformer in operation generates heat in the winding, and that heat is transferred to the oil via conduction. Heated oil then flows to the radiators by convection. Oil supplied from the radiators, being cooler, cools the winding. There are several important properties such as dielectric strength, flash point, viscosity, specific gravity and pour point and all of them have to be considered when qualifying an oil for use in transformers. Normally mineral oil is used, but coconut oil has been shown to possess all the properties needed to function as an environmentally friendly and economic replacement to mineral oil for this purpose.[22]

[edit] Herbicide

Acids derived from coconut oil can be used as herbicides, for a more environmentally friendly way of combatting weeds. It is also considered unproblematic for people who have sensitivity to synthethic herbicides.[23]

[edit] Personal uses

[edit] Cosmetics and skin treatments

Coconut oil is excellent as a skin moisturizer and softener. A study shows that extra virgin coconut oil is effective and safe when used as a moisturizer, with absence of adverse reactions.[24] A study found that coconut oil helped prevent protein loss from the wet combing of hair when used for fourteen hours[25] as a conditioner before washing the hair.[26]

[edit] Sexual lubrication

There are widespread reports of the use of coconut oil as a sexual lubricant.[27] Like other oil-based intimate lubricants, coconut oil should not be used with latex condoms.

[edit] Medicine

A single-blind randomized controlled trial on children with pneumonia at the Philippine Children's Medical Center found that coconut oil accelerated the normalization of respiratory rate and resolution of crackles.[28]

A randomized double-blind clinical trial with 40 women exhibiting obesity found that supplementation with coconut oil promoted a reduction in obesity without causing dyslipidemia.[29]

[edit] See also

[edit] References

  1. ^ Fife, Bruce (2005). Coconut Cures. Piccadilly Books, Ltd.. pp. 184–185. ISBN 978-0-941599-60-3
  2. ^ [U.G. Ohler, Coconut: Tree of Life,Kuene, 1984 Pg. 339],
  3. ^ [Woodruff, Jasper Guy, Ph.D. "Coconuts: Production, Processing, Products." The Avi Publishing Co, Inc, 1970]
  4. ^ Direct Micro Expelling, Kokonut Pacific Pty Ltd, accessed April, 2008
  5. ^ Asian and Pacific Coconut Community
  6. ^ APCC STANDARDS FOR VIRGIN COCONUT OIL Asian and Pacific Coconut Community, Jakarta, Indonesia
  7. ^ Joint Statement on Philippine National Standard for Virgin Coconut Oil as food
  8. ^ "Oilseeds: World Markets and Trade" Table 03: Major Vegetable Oils: World Supply and Distribution (Commodity View) http://www.fas.usda.gov/psdonline/circulars/oilseeds.pdf
  9. ^ Tropics Best Coconut Oil Manufacturer
  10. ^ ([1] Quality First International)
  11. ^ Foale, M. (2003). The Coconut Odyssey: The Bounteous Possibilities of the Tree of Life. Australian Centre for International Agricultural Research; Canberra. pp. 184–5.
  12. ^ McGlone OC, Canales A, Carter JV (1986). "Coconut oil extraction by a new enzymatic process". J Food Sci 51: 695–7. doi:10.1111/j.1365-2621.1986.tb13914.x.
  13. ^ International Wellness Directory
  14. ^ http://www.cspinet.org/new/200911182.html
  15. ^ Weihenstephan vegetable oil fuel standard (German Rapeseed Fuel Standard)
  16. ^ In Vanuatu, A Proving Ground for Coconut Oil As An Alternative Fuel
  17. ^ Coconut fuel - PRI's The World
  18. ^ Coconut Oil for Power Generation by EPC in Samoa - Jan Cloin
  19. ^ "Coconut oil powers island's cars". BBC. 2007-05-08. http://news.bbc.co.uk/1/hi/world/asia-pacific/6634221.stm.
  20. ^ The Coconut Revolution: a documentary film
  21. ^ Romares-Sevilla, J (2008-01-17). "Davao-based firm sees expansion of bio-tech oil market". Sun.Star Superbalita Davao. http://web.archive.org/web/20080121082827/http://www.sunstar.com.ph/static/dav/2008/01/17/bus/davao.based.firm.sees.expansion.of.bio.tech.oil.market.html. Retrieved 2008-07-14.
  22. ^ Coconut Oil As An Alternative To Transformer Oil
  23. ^ Roads and footpaths - weed control (from the Auckland City Council website. Accessed 2010-01-21.)
  24. ^ Agero AL, Verallo-Rowell VM (September 2004). "A randomized double-blind controlled trial comparing extra virgin coconut oil with mineral oil as a moisturizer for mild to moderate xerosis". Dermatitis 15 (3): 109–16. PMID 15724344.
  25. ^ "For the oil application, to each hair tress was applied 0.2 ml of oil (the quantity of oil normally applied by an Indian hair oil user). It was allowed to remain on the hair for at least 14 hr to simulate overnight application (the normal habit of the Indian consumer). These hair tresses were then subjected to both protein loss and WRI tests." p. 179 of Aarti S. Rele and R. B. Mohile: "Effect of mineral oil, sunflower oil, and coconut oil on prevention of hair damage", J. Cosmet. Sci., 54 175-192 (March/April 2003). Downloaded Sep 20, 2010, from http://journal.scconline.org/pdf/cc2003/cc054n02/p00175-p00192.pdf
  26. ^ http://journal.scconline.org/pdf/cc2003/cc054n02/p00175-p00192.pdf
  27. ^ http://www.peoplespharmacy.com/2008/06/09/coconut-oil-for-2/
  28. ^ Erguiza, Gilda; J; R; R (October 2008). "The effect of virgin coconut oil supplementation for community-acquired pneumonia in children aged 3 months to 60 months admitted at the Philippine Children's Medical Center: a single blinded randomized controlled trial.". Chest 134 (4): p139001. http://meeting.chestpubs.org/cgi/content/abstract/134/4/p139001.
  29. ^ Assunção, ML; Ferreira, HS; Dos Santos, AF; Cabral Jr, CR; Florêncio, TM (July 2009). "Effects of dietary coconut oil on the biochemical and anthropometric profiles of women presenting abdominal obesity.". Lipids 44 (7): 593–601. doi:10.1007/s11745-009-3306-6. PMID 19437058.

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