Coconut oil

A cracked coconut and a bottle of coconut oil

Coconut oil, or copra oil, is an edible oil extracted from the kernel or meat of mature coconuts harvested from the coconut palm (Cocos nucifera). It has various applications. Because of its high saturated fat content, it is slow to oxidize and, thus, resistant to rancidification, lasting up to six months at 24 °C (75 °F) without spoiling.[1]

Due to its high levels of saturated fat, the World Health Organization, United States Food and Drug Administration, International College of Nutrition, the United States Department of Health and Human Services, American Dietetic Association, American Heart Association, British National Health Service, British Nutrition Foundation and Dietitians of Canada advise against regular consumption of coconut oil.

Production

Dry process

Traditional way of making coconut oil using an ox-powered mill in Seychelles

Coconut oil can be extracted through "dry" or "wet" processing. Dry processing requires that the meat be extracted from the shell and dried using fire, sunlight, or kilns to create copra.[2] The copra is pressed or dissolved with solvents, producing the coconut oil and a high-protein, high-fiber mash. The mash is of poor quality for human consumption and is instead fed to ruminants; there is no process to extract protein from the mash. A portion of the oil extracted from copra is lost to the process of extraction.

Wet process

The all-wet process uses raw coconut rather than dried copra, and the protein in the coconut creates an emulsion of oil and water.[3] The more problematic step is breaking up the emulsion to recover the oil. This used to be done by prolonged boiling, but this produces a discolored oil and is not economical. Modern techniques use centrifuges and pre-treatments including cold, heat, acids, salts, enzymes, electrolysis, shock waves, or some combination. Despite numerous variations and technologies, wet processing is less viable than dry processing due to a 10–15% lower yield, even compared to the losses due to spoilage and pests with dry processing. Wet processes also require investment of equipment and energy, incurring high capital and operating costs.[4]

Proper harvesting of the coconut (the age of a coconut can be 2 to 20 months when picked) makes a significant difference in the efficacy of the oil-making process. Copra made from immature nuts is more difficult to work with and produces an inferior product with lower yields.[5]

Conventional coconut oil processors use hexane as a solvent to extract up to 10% more oil than produced with just rotary mills and expellers. They then refine the oil to remove certain free fatty acids to reduce susceptibility to rancidification. Other processes to increase shelf life include using copra with a moisture content below 6%, keeping the moisture content of the oil below 0.2%, heating the oil to 130–150 °C (266–302 °F) and adding salt or citric acid.[6]

Virgin coconut oil (VCO) can be produced from fresh coconut milk, meat, or residue. Producing it from the fresh meat involves removing the shell and washing, then either wet-milling or drying the residue, and using a screw press to extract the oil. VCO can also be extracted from fresh meat by grating and drying it to a moisture content of 10–12%, then using a manual press to extract the oil. Producing it from coconut milk involves grating the coconut and mixing it with water, then squeezing out the oil. The milk can also be fermented for 36–48 hours, the oil removed, and the cream heated to remove any remaining oil. A third option involves using a centrifuge to separate the oil from the other liquids. Coconut oil can also be extracted from the dry residue left over from the production of coconut milk.[6]

A thousand mature coconuts weighing approximately 1,440 kilograms (3,170 lb) yield around 170 kilograms (370 lb) of copra from which around 70 litres (15 imp gal) of coconut oil can be extracted.[7]

Refined oil

"Refined, bleached, and deodorized" (RBD) oil is usually made from copra, dried coconut kernel, which is placed in a hydraulic press with added heat and the oil is extracted. This yields practically all the oil present, amounting to more than 60% of the dry weight of the coconut. This "crude" coconut oil is not suitable for consumption because it contains contaminants and must be refined with further heating and filtering.[8]

Another method for extraction of coconut oil involves the enzymatic action of alpha-amylase, polygalacturonases, and proteases on diluted coconut paste.[9]

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.

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 24 °C (76 °F), 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 36–40 °C (97–104 °F).

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 the partial hydrogenation process, some of these are transformed into trans fatty acids.[10]

Fractionation

Fractionated coconut oil provides fractions of the whole oil so that its different fatty acids can be separated for specific uses. Lauric acid, a 12-carbon chain fatty acid, is often removed because of its high value for industrial and medical purposes.[11] The fractionation of coconut oil can also be used to isolate caprylic acid and capric acid, which are medium-chain triglycerides, as these are used for medical applications, special diets and cosmetics, sometimes also being used as a carrier oil for fragrances.[12]

Figures

The United States Department of Agriculture has published estimated production figures for coconut oil as follows; tabulated years are from October 1 through September 30:[13]

World coconut oil production (million tonnes)[13]
Year2005–06 2006–07 2007–08 2008–09 2009–10 2010–11 2011–12 2012–13 2013–14 2014–15 2015–16
Total Supply 5.84 5.47 5.85 5.62 6.66 6.11 6.01 6.13 5.55 5.46 5.40

Coconut oil makes up around 2.5% of world vegetable oil production.

Standards

The World Health Organization's Codex Alimentarius guidelines on food, food production, and food safety, published by the Food and Agriculture Organization, includes standards for commercial partners who produce coconut oil for human consumption.[14]

The Asian and Pacific Coconut Community (APCC), whose 18 members produce about 90 per cent of the coconut sold commercially,[15] has published its standards for virgin coconut oil (VCO), defining virgin coconut oil as obtained from fresh, mature coconut kernels through means that do not "lead to alteration of the oil."[16]

Composition and comparison

The approximate concentration of fatty acids in coconut oil (midpoint of range in source):

Fatty acid content of coconut oil
Type of fatty acid pct
Caprylic saturated C8
  
 7%
Decanoic saturated C10
  
 8%
Lauric saturated C12
  
 48%
Myristic saturated C14
  
 16%
Palmitic saturated C16
  
 9.5%
Oleic monounsaturated C18:1
  
 6.5%
Other
  
 5%
black: Saturated; grey: Monounsaturated; blue: Polyunsaturated

The following table provides information about the composition of coconut oil and how it compares with other vegetable oils.

Vegetable oils
Type Processing
Treatment 		Saturated
fatty acids[17] 		Mono-
unsaturated
fatty acids[17] 		Polyunsaturated fatty acids Oleic acid
(ω-9)		Smoke point
Total poly[17] linolenic acid
(ω-3) 		Linoleic acid
(ω-6)
Avocado   11.560 70.554 13.486 1 12.5   480 °F (249 °C)[18]
Canola (rapeseed)   7.365 63.276 28.142 10 10   400 °F (204 °C)[19]
Coconut   91.000 6.000 3.000   2 6 350 °F (177 °C)[19]
Corn[20]   12.948 27.576 54.677 1 58 28 450 °F (232 °C)
Cottonseed   25.900 17.800 51.900 1 54 19 420 °F (216 °C)[20]
Flaxseed/Linseed (European)[21]   7.500 15.500 79.000 64 15 11 225 °F (107 °C)
Olive   14.000 72.000 14.000 1.5 15   380 °F (193 °C)[19]
Palm   49.300 37.000 9.300   10 40 455 °F (235 °C)
Peanut   16.900 46.200 32.000   32 48 437 °F (225 °C)[20]
Safflower (>70% linoleic)   8.000 15.000 75.000       410 °F (210 °C)[19]
Safflower (high oleic)   7.541 75.221 12.820       410 °F (210 °C)[19]
Soybean   15.650 22.783 57.740 7 50 24 460 °F (238 °C)[20]
Sunflower (<60% linoleic)   10.100 45.400 40.100 0.2 39.8 45.3 440 °F (227 °C)[20]
Sunflower (>70% oleic)   9.859 83.689 3.798       440 °F (227 °C)[20]
Cottonseed (hydrogenated)[17] Hydrogenated 93.600 1.529 0.587   0.287  
Palm (hydrogenated) Hydrogenated 47.500 40.600 7.500      
Soybean (hydrogenated)[17] Hydrogenated 21.100 73.700 0.400 0.096    
Values as percent (%) by weight of total fat.

Health claims

Many health organizations advise against the consumption of coconut oil due to its high levels of saturated fat, including the United States Food and Drug Administration,[22] World Health Organization,[23] International College of Nutrition,[24] the United States Department of Health and Human Services,[25] American Dietetic Association,[26] American Heart Association,[27] British National Health Service,[28] British Nutrition Foundation[29][30] and Dietitians of Canada.[31]

Coconut oil contains a large proportion of lauric acid, a saturated fat that raises total blood cholesterol levels by increasing both the amount of high-density lipoprotein (HDL) cholesterol and low-density lipoprotein (LDL) cholesterol.[32] Although this may create a more favorable total blood cholesterol profile, this does not exclude the possibility that persistent consumption of coconut oil may increase the risk of cardiovascular disease through other mechanisms, particularly via the marked increase of blood cholesterol induced by lauric acid.[32] Because the majority of saturated fat in coconut oil is lauric acid,[32] coconut oil may be preferred over partially hydrogenated vegetable oil when solid fats are used in the diet.[33]

Due to its high content of saturated fat with corresponding high caloric burden, regular use of coconut oil in food preparation may promote weight gain.[30]

Uses

Coconut oil
Nutritional value per 100g
Energy 3,607 kJ (862 kcal)
100
Saturated 86.5
Monounsaturated 5.8
Polyunsaturated 1.8
Vitamins
Vitamin E
(1%)

0.09 mg

Vitamin K
(0%)

0.5 μg

Minerals
Iron
(0%)

0.04 mg

Percentages are roughly approximated using US recommendations for adults.
Source: USDA Nutrient Database

In food

Solidified "coconut fat"

Coconut oil is commonly used in cooking, especially for frying, and is a common flavor in many South Asian curries. In recent years despite its high saturated fat content, virgin coconut oil has become popular and was described in a New York Times article as having a "haunting, nutty", flavor with a touch of sweetness, which works well in baked goods, pastries, and sautés.[34] Used by movie theatre chains to pop popcorn, coconut oil adds considerable saturated fat and calories to the snackfood,[35] possibly leading to an increase in energy balance and weight gain.[30]

Other culinary uses include replacing solid fats produced through hydrogenation in baked and confectionery goods.[33] Hydrogenated or partially hydrogenated coconut oil is often used in non-dairy creamers and snack foods, including popcorn. Hydrogenated coconut oil is sold in Australia under the brand-name Copha and is the main ingredient in Australian snacks such as chocolate crackles and White Christmas.

The smoke point of coconut oil is 177 °C (351 °F).

Industry

Coconut oil has been tested for use as a feedstock for biodiesel to use 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 typically is transesterified to make biodiesel. Use of B100 (100% biodiesel) is possible only in temperate climates, as the gel point is approximately 10 °C (50 °F). The oil must meet the Weihenstephan standard[36] to use pure vegetable oil as a fuel. Moderate to severe damage from carbonisation and clogging would occur in an unmodified engine.

The Philippines, Vanuatu, Samoa, and several other tropical island countries use coconut oil as an alternative fuel source to run automobiles, trucks, and buses, and to power generators.[37] Coconut oil is currently used as a fuel for transport in the Philippines.[38][39] Further research into the potential of coconut oil as a fuel for electricity generation is being carried out in the islands of the Pacific, although to date it appears that it is not useful as a fuel source due to the cost of labour and supply constraints.[40]

Coconut oil has been tested for use as an engine lubricant[41] and as a transformer oil.[42]

Acids derived from coconut oil can be used as herbicides.[43]

Coconut oil (and derivatives, such as coconut fatty acid) are used as raw materials in the manufacture of surfactants such as cocamidopropyl betaine, cocamide MEA, and cocamide DEA.

Personal uses

Homemade coconut oil

Coconut oil is as effective and safe as mineral oil when used as a moisturizer for mild to moderate xerosis (dry skin)[44] and was shown in one study to reduce protein loss when used in hair.[45]

Before the advent of electrical lighting, coconut oil was the primary oil used for illumination in India and was exported as cochin oil.[46]

Coconut oil is an important base ingredient for the manufacture of soap. Soap made with coconut oil tends to be hard, though it retains more water than soap made with other oils and therefore increases manufacturer yields. It is more soluble in hard water and salt water than other soaps allowing it to lather more easily.[47] A basic coconut oil soap is clear when melted and a bright white when hardened.[48]

A repellent made from coconut oil may be effective in preventing tungiasis caused by chigoe fleas.[49]

See also

References

  1. ↑ "Coconut oil". Transport Information Service, German Insurance Association, Berlin. 2015.
  2. ↑ Grimwood, BE; Ashman F; Dendy DAV; Jarman CG; Little ECS; Timmins WH (1975). Coconut Palm Products – Their processing in developing countries. Rome: FAO. pp. 49–56. ISBN 978-92-5-100853-9.
  3. ↑ Hamid, M.A.; Sarmidi, M.R.; Mokhtar, T.H.; Sulaiman, W.R.W.; Aziz, R.A. (2011). "Innovative Integrated Wet Process for Virgin Coconut Oil Production" (PDF). Journal of Applied Sciences. 11 (13): 2467. doi:10.3923/jas.2011.2467.2469.
  4. ↑ Grimwood et al., 1975, pp. 193–210.
  5. ↑ Grimwood et al., 1975, p. 29.
  6. 1 2 Kurian; Peter KV (2007). Commercial Crops Technology: Vol.08. Horticulture Science Series. New India Publishing. pp. 202–6. ISBN 81-89422-52-9.
  7. ↑ Bourke, RM; Harwood T (2009). Food and Agriculture in Papua New Guinea. Australian National University. p. 327. ISBN 978-1-921536-60-1.
  8. ↑ Foale, M. (2003). "The Coconut Odyssey: The Bounteous Possibilities of the Tree of Life" (PDF). Canberra: Australian Centre for International Agricultural Research. pp. 115–116.
  9. ↑ McGlone OC, Canales A, Carter JV (1986). "Coconut oil extraction by a new enzymatic process". J Food Sci. 51 (3): 695–697. doi:10.1111/j.1365-2621.1986.tb13914.x.
  10. ↑ Foster, R., Williamson, C.S. and Lunn, J. (2009). "BRIEFING PAPER: Culinary Oils And Their Health Effects". Nutrition Bulletin. 34 (1): 4–47. doi:10.1111/j.1467-3010.2008.01738.x.
  11. ↑ Gervajio, G. C. (2005). "Fatty Acids and Derivatives from Coconut Oil". Bailey's Industrial Oil and Fat Products. doi:10.1002/047167849X.bio039. ISBN 047167849X.
  12. ↑ Emil Raymond Riegel; James Albert Kent (2003). Riegel's Handbook of Industrial Chemistry. Springer. pp. 1100–1117. ISBN 978-0-306-47411-8. Retrieved 20 October 2012.
  13. 1 2 "Table 19: World: Palm Oil, Coconut Oil, and Fish Meal Supply and Distribution" (PDF). United States Department of Agriculture. 2011-04-08. Retrieved 2011-04-14.
  14. ↑ "Codex Standard for Named Vegetable Oils (Codex Stan 210-1999, Revision 3)" (PDF). Codex Alimentarius. Food and Agriculture Organization. 2009. Retrieved 2011-08-09.
  15. ↑ "About us". Asian and Pacific Coconut Community. Archived from the original on 2011-08-29. Retrieved 2011-08-09.
  16. ↑ "APCC Standards for Virgin Coconut Oil" (PDF). Jakarta, Indonesia: Asian and Pacific Coconut Community. 2003. Retrieved 2011-08-09.
  17. 1 2 3 4 5 "Nutrient database, Release 24". United States Department of Agriculture. All values in this column are from the USDA Nutrient database unless otherwise cited.
  18. ↑ What is unrefined, extra virgin cold-pressed avocado oil?, The American Oil Chemists’ Society
  19. 1 2 3 4 5 Katragadda, H. R.; Fullana, A. S.; Sidhu, S.; Carbonell-Barrachina, Á. A. (2010). "Emissions of volatile aldehydes from heated cooking oils". Food Chemistry. 120: 59. doi:10.1016/j.foodchem.2009.09.070.
  20. 1 2 3 4 5 6 Wolke, Robert L. (May 16, 2007). "Where There's Smoke, There's a Fryer". The Washington Post. Retrieved March 5, 2011.
  21. ↑ Fatty acid composition of important plant and animal fats and oils (German) 21 December 2011, Hans-Jochen Fiebig, Münster
  22. ↑ "Around the Block Nutrition Facts at a Glance: More on Nutrients to Get Less Of". Food and Drug Administration. 2012-09-05. Archived from the original on 2014-02-01. Retrieved 2014-01-25.
  23. ↑ "Avoiding Heart Attacks and Strokes" (PDF). World Health Organization. Retrieved 2011-04-06.
  24. ↑ Singh RB, Mori H, Chen J, Mendis S, Moshiri M, Zhu S, Kim SH, Sy RG, Faruqui AM (December 1996). "Recommendations for the prevention of coronary artery disease in Asians: a scientific statement of the International College of Nutrition". J Cardiovasc Risk. 3 (6): 489–494. doi:10.1097/00043798-199612000-00002. PMID 9100083.
  25. ↑ "Dietary Guidelines for Americans 2010" (PDF). Department of Health and Human Services. Retrieved 17 March 2011.
  26. ↑ "American Dietetic Association and Dietitians of Canada Offer Up-to-Date Guidance on Dietary Fat". American Dietetic Association. Archived from the original on 2012-03-19. Retrieved 2011-03-16.
  27. ↑ "Tropical Oils". American Heart Association. Retrieved 2011-03-16.
  28. ↑ "Lower your cholesterol". National Health Service. Retrieved 2011-03-16.
  29. ↑ Foster R, Williamson CS, Lunn J (2009). "Culinary oils and their health effects" (PDF). British Nutrition Foundation, Nutrition Bulletin. 34: 4–47.
  30. 1 2 3 Lockyer S, Stanner S (2016). "Coconut oil - a nutty idea?". Nutrition Bulletin. 41 (1): 42–54. doi:10.1111/nbu.12188.
  31. ↑ "Heart Healthy Eating: Cholesterol". Dietitians of Canada. 2010-09-01. Retrieved 2013-07-05.
  32. 1 2 3 Mensink RP, Zock PL, Kester AD, Katan MB (May 2003). "Effects of dietary fatty acids and carbohydrates on the ratio of serum total to HDL cholesterol and on serum lipids and apolipoproteins: a meta-analysis of 60 controlled trials" (PDF). Am J Clin Nutr. 77 (5): 1146–55. PMID 12716665.
  33. 1 2 Tarrago-Trani, MT; Phillips, KM; Lemar, LE; Holden, JM (2006). "New and existing oils and fats used in products with reduced trans-fatty acid content" (PDF). Journal of the American Dietetic Association. 106 (6): 867–880. doi:10.1016/j.jada.2006.03.010. PMID 16720128.
  34. ↑ Clark, M (2011-03-01). "Once a Villain, Coconut Oil Charms the Health Food World". The New York Times. Retrieved 2011-03-02.
  35. ↑ "Two Thumbs Down' for Movie Theater Popcorn". Center for Science in the Public Interest. 2009-11-18. Retrieved 2011-04-24.
  36. ↑ "Weihenstephan vegetable oil fuel standard (German Rapeseed Fuel Standard)". Retrieved 2011-08-09.
  37. ↑ "In Vanuatu, A Proving Ground for Coconut Oil As An Alternative Fuel". One Country. Retrieved 2011-08-09.
  38. ↑ "Coconut fuel". The World. Public Radio International. Retrieved 2011-08-09.
  39. ↑ Watson, Todd (1 August 2013). "Coconut biodiesel drives the Philippines". Inside Investor. Retrieved 11 August 2013.
  40. ↑ "Economics of Rural Renewable Energy Technologies". Secretariat of the Pacific Community – Applied Geoscience and Technology Division. 2010-06-14. Retrieved 2011-08-09.
  41. ↑ Romares-Sevilla, J (2008-01-17). "Davao-based firm sees expansion of bio-tech oil market". Sun.Star Superbalita Davao. Archived from the original on 2008-01-21. Retrieved 2008-07-14.
  42. ↑ DC, Abeysundara; Weerakoon, C; Lucas, JR; Gunatunga, KAI; Obadagee, KC (2001). "Coconut Oil As An Alternative To Transformer Oil" (PDF). ERU Symposium.
  43. ↑ James, TK; Rahman A (2005). "Efficacy of several organic herbicides and glyphosate formulations under simulated rainfall" (PDF). New Zealand Plant Protection. 58: 157–163.
  44. ↑ 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. doi:10.2310/6620.2004.04006. PMID 15724344.
  45. ↑ Rele, A.; Mohile, R. (2003). "Effect of mineral oil, sunflower oil, and coconut oil on prevention of hair damage" (pdf). Journal of cosmetic science. 54 (2): 175–192. PMID 12715094.
  46. ↑ Brady, GS; Clauser, HR; Vaccari, JA (2002). Materials Handbook – An encyclopedia for managers, technical professionals, purchasing and production managers, technicians, and supervisors (15 ed.). McGraw-Hill. pp. 250–251. ISBN 978-0-07-136076-0.
  47. ↑ Alsberg, CL; Taylor AE (1928). The Fats and Oils – A General Overview (Fats and Oils Studies No. 1). Stanford University Press. p. 86. ISBN 0-8047-0330-2.
  48. ↑ Browning, M (2003). 300 Handcrafted Soaps – Great Melt & Pour Projects. Sterling Publishing. p. 9. ISBN 978-1-4027-0797-1.
  49. ↑ Feldmeier, H (2009). "Tungiasis and cutaneous larva migrans: unpleasant travel souvenirs". Medizinische Monatsschrift für Pharmazeuten. 32 (12): 440–4. PMID 20088345.

Further reading

External links

This article is issued from Wikipedia - version of the 12/3/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.