Refining coconut oil is a multi-step process that removes impurities, odor, and color from crude or virgin coconut oil, producing a neutral-flavored oil with a higher smoke point. The industrial method follows a sequence known as RBD: refining (degumming and neutralization), bleaching, and deodorizing. While full refinement at home isn’t practical without specialized equipment, you can partially purify homemade coconut oil using simpler techniques.
The Four Stages of Industrial Refining
Commercial coconut oil refining follows a consistent sequence, each step targeting a different category of unwanted compounds.
Degumming
The first step removes phospholipids, commonly called gums, which can make oil cloudy and reduce its shelf life. The crude oil is heated to around 60°C (140°F) and mixed with a small amount of phosphoric acid, typically about 0.2% of the oil’s weight. This mixture is agitated gently for 30 minutes, then allowed to rest so the gums separate out. The oil is then washed with water at 70°C (158°F) and stirred slowly for another 20 minutes before the water layer is removed.
Neutralization
Free fatty acids give crude coconut oil a sharp, unpleasant taste and accelerate spoilage. To neutralize them, the degummed oil is heated to about 80°C (176°F), and a dilute sodium hydroxide solution is added. The sodium hydroxide reacts with the free fatty acids to form soap, which settles to the bottom and is drained off. The oil is washed again with water to remove any remaining soap residue.
Bleaching
Despite the name, bleaching doesn’t use bleach. Activated charcoal or a filtering clay called diatomaceous earth is mixed into the oil to absorb pigments, trace metals, and remaining impurities. The mixture is then filtered, pulling out the charcoal or clay along with everything it has absorbed. This step is what gives refined coconut oil its pale, uniform appearance compared to the slightly yellowish tint of virgin oil.
Deodorizing
The final step strips out volatile compounds responsible for coconut oil’s natural aroma. Steam is injected through the hot oil under vacuum at temperatures above 200°C (392°F). The low pressure lowers the boiling point of odor compounds, allowing the steam to carry them away without overheating the oil itself. This is what makes refined coconut oil smell and taste neutral, a key reason many people prefer it for cooking savory dishes.
Can You Refine Coconut Oil at Home?
True RBD refining requires industrial equipment, particularly the vacuum deodorizer. However, you can improve the purity and clarity of homemade or crude coconut oil with a few accessible techniques.
Water washing: Heat your coconut oil to about 60–70°C until fully melted. Add an equal volume of warm water and stir gently for 15 to 20 minutes. Let the mixture sit until the oil and water fully separate, then carefully pour or ladle off the oil layer. The water pulls out water-soluble impurities, proteins, and some of the compounds that cause rancidity. You can repeat this two or three times for a cleaner result.
Gravity settling and filtering: After washing, let the oil sit undisturbed for several hours. Fine particles and moisture will settle to the bottom. Pour the clear oil off the top through a cheesecloth or fine mesh strainer. For an even cleaner oil, filter through a coffee filter, though this is slow with thick oil and works best when the oil is warm and fully liquid.
Gentle heating: Warming the oil to around 100°C (212°F) for a short period drives off residual moisture, which is the main cause of mold and early spoilage in homemade coconut oil. Keep the heat low and steady. Once the oil stops producing tiny bubbles (a sign that water is evaporating), remove it from heat. This won’t deodorize the oil the way industrial steam distillation does, but it significantly extends storage life.
These home methods will produce a cleaner, more stable oil, but it will still retain coconut flavor and aroma. If you need a truly neutral oil, purchasing commercially refined coconut oil is the more realistic option.
What Refining Changes in the Oil
Refining improves coconut oil’s cooking performance but comes with nutritional trade-offs. The most significant gain is a higher smoke point. Virgin coconut oil starts smoking at about 177°C (350°F), which limits its usefulness for frying or high-heat sautéing. Refined coconut oil handles temperatures of 204–232°C (400–450°F), putting it in the same range as many vegetable oils.
The trade-off is a loss of antioxidants. Virgin coconut oil contains phenolic compounds that act as natural antioxidants, protecting both the oil and potentially your cells from oxidative damage. Research comparing virgin and RBD coconut oil has found that the refining process degrades or removes most of these phenolics, leaving refined oil with significantly lower antioxidant activity. Virgin oil also retains more phytosterols, plant compounds associated with cholesterol management.
The fatty acid profile, which is the main reason people use coconut oil in the first place, stays largely the same after refining. The medium-chain fatty acids, including lauric acid, survive the process intact.
Shelf Life Differences
Somewhat counterintuitively, virgin coconut oil lasts longer than refined. Virgin coconut oil stays good for three to five years when stored properly, while refined coconut oil typically lasts 18 to 36 months. The phenolic antioxidants naturally present in virgin oil act as built-in preservatives, slowing the oxidation that causes rancidity. Refining strips these out, so even though the oil starts cleaner, it has less natural protection over time.
For either type, store the oil in a cool, dark place with the lid tightly sealed. Coconut oil is solid below about 24°C (76°F) and liquid above it. Both states are fine, and cycling between them doesn’t harm the oil.
A Note on Solvent Extraction
Some large-scale producers use hexane, a chemical solvent, to extract oil from dried coconut meat (copra) before the refining process begins. This is more common with low-oil-content seeds but is sometimes used for coconut as well. The solvent is removed through distillation and steam injection before the oil reaches consumers. European regulations cap hexane residues in finished oils at 1 mg/kg. U.S. regulations are less specific, with the FDA not setting explicit residue limits for hexane in food-grade oils.
If solvent residues concern you, look for coconut oil labeled “expeller-pressed” or “cold-pressed,” which indicates mechanical extraction without chemical solvents. These oils can still be refined through the RBD process afterward, giving you a neutral oil without solvent exposure.