Coconut Oil

KERAFED

Coconut oil is an edible oil extracted from the kernel or meat of matured coconuts harvested from the coconut palm. 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, which makes it suited to methods of cooking at high temperatures like frying. Because of its stability, it is slow to oxidize and, thus, resistant to rancidity, lasting up to two years owing to the high saturated fat content.

Coconut oil can be extracted through ‘dry’ or ‘wet’ processing. Dry processing requires the meat to be extracted from the shell and dried using fire, sunlight, or kilns to create copra. 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. The preparation and storage of copra often occurs in unhygienic conditions, yielding poor quality oil that requires refining. A portion of the oil extracted from copra is lost to the process of extraction.

The all-wet process uses raw coconut rather than dried copra, and the protein in the coconut creates an emulsion of oil and water. 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.

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. Virgin coconut oil (VCO) can be produced from fresh coconut meat, milk 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.

RBD stands for ‘refined, bleached, and deodorized.’ RBD oil is usually made from copra (dried coconut kernel). The dried copra is placed in a 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. This ‘crude’ coconut oil is not suitable for consumption because it contains contaminants and must be refined with further heating and filtering. 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.

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). Coconut oil contains only 6% monounsaturated and 2% polyunsaturated fatty acids.

Many health organizations advise against the consumption of high amounts of coconut oil due to its high levels of saturated fat, including the FDA, World Health Organization, American Heart Association, and the British National Health Service. However, Thomas Brenna, a professor of nutritional sciences at Cornell University, stated that, ‘Most of the studies involving coconut oil were done with partially hydrogenated coconut oil, which researchers used because they needed to raise the cholesterol levels of their rabbits in order to collect certain data. Virgin coconut oil, which has not been chemically treated, is a different thing in terms of a health risk perspective. And maybe it isn’t so bad for you after all.’ Virgin coconut oil is composed mainly of medium-chain triglycerides,which may not carry the same risks as other saturated fats.

Coconut oil contains a large proportion of lauric acid—a saturated fat that raises blood cholesterol levels by increasing the amount of both high-density lipoprotein (HDL) cholesterol and low-density lipoprotein (LDL) cholesterol. It is also found in significant amounts in laurel oil, palm kernel oil (not to be confused with palm oil), human and animal breast milk, and sebaceous gland secretions. This may create a more favorable blood cholesterol profile, though it is unclear if coconut oil may promote atherosclerosis through other pathways. The effects of coconut oil on the peripheral nervous system in animal models is that it is acutely anti-inflammatory, although chronically neutral. Because much of the saturated fat of coconut oil is in the form of lauric acid, coconut oil may be a better alternative to partially hydrogenated vegetable oil when solid fats are required.

Advocacy against coconut and palm oils in the 1970s and 80s due to their perceived danger as a saturated fat caused companies to instead substitute trans fats, unaware of their health-damaging effects.

Coconut oil is commonly used in cooking, especially for frying and is a common flavor in many South Asian curries. In recent years, virgin coconut oil has become increasingly popular in natural food circles and with vegans. It was described in a ‘New York Times’ article as having a ‘haunting, nutty,’ flavor that also has a touch of sweetness, which works well in baked goods, pastries, and sautés. Coconut oil is used by movie theater chains to pop popcorn, adding a large amount of saturated fat in the process. Other culinary uses include replacing solid fats produced through hydrogenation in baked and confectionery goods. Hydrogenated or partially hydrogenated coconut oil is often used in non-dairy creamers, and snack foods.

Before the advent of electrical lighting, coconut oil was the primary oil used for illumination in India and was exported as cochin oil. 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. Coconut oil has also been tested for use as an engine lubricant. Acids derived from coconut oil can be used as herbicides. Coconut oil can be used as a skin moisturizer, helping with dry skin and reduces protein loss when used in hair. Coconut oil can also be used as sexual lubricant, although it can damage latex condoms. Coconut oil is an important base ingredient for the manufacture of soap. Soap made with coconut oil tends to be hard, although it retains more water than those 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. A basic coconut oil soap is clear when melted and a bright white when hardened.

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