Palm Oil Deacidification Process

Palm oil deacidification process is necessary because crude palm oil naturally contains free fatty acids (FFAs), which are the byproducts of the palm oil extraction process. These FFAs contribute to the palm oil’s acidity level, which can negatively affect its taste, odor, and shelf life. High acidity levels can make the palm oil go rancid more quickly, leading to off-flavors and reduced nutritional value.

Palm Oil Deacidification Process

Palm oil deacidification is a core refining step to remove free fatty acids (FFA) from crude palm oil (CPO), lowering acid value, improving stability, and meeting edible oil standards. Two dominant processes are used: chemical deacidification (alkali refining) and physical deacidification (steam distillation).

Chemical Deacidification (Alkali Refining)

The alkali refining of palm oil is one kind of palm oil deacidification method. It is called chemical refining method, usually used in batch type and semi-continous palm oil refinery plant.

According to acid-base neutralization principle, add alkali into degummed palm oil, react with Free Fatty Acid(FFA), and last produce nigre which can be used to make soap.

Process of alkali refining of palm oil

1. Heating: After degumming, the crude palm oil should be under 60-70℃ temperature.

2. Neutralizing: Add alkali, stir the oil slowly, then the alkali will react with FFA, and finally get the by-product–nigre.

3. Settling: After reaction, the oil should be settled for a long time to make the nigre settle down.

4. Separating: Separate the nigre from the oil.

5. Washing: About 500 ppm soaps still remain in the separated neutralized oil, adding 5% of hot water to reduce the residual content of soaps, because hot water will absorb oil soap and other impurities.

After alkali refining of palm oil, the acid value of the palm oil will be low, and it is more easily to store. But if you want to get higher quality palm oil, the decolorization and deodorization of palm oil are also necessary processes.

Physical Deacidification (Steam Distillation / Physical Refining)

Principle: Exploit volatility difference—FFA vaporizes at 240–260°C under high vacuum (<1–4 mbar) and is stripped by direct steam; glycerides remain liquid.

Critical Precondition: Deep degumming (phosphorus <10–15 ppm) to prevent phospholipid charring.

Process Flow:

• Degumming: Add 0.1–0.2% phosphoric acid; centrifuge to remove gums.
• Bleaching: Adsorb pigments with activated clay (1–2%) before high heat.
• Steam Stripping: Heat oil to 250–260°C; inject steam in a vacuum tower to distill FFA.
• FFA Recovery: Condense distillate to recover high-purity fatty acids (valuable byproduct).
• Cooling: Cool refined oil under vacuum to avoid oxidation.

Pros:

• No soapstock, minimal wastewater.
• Neutral oil loss <1% (higher yield).
• FFA recycled for oleochemicals.
• Combined with deodorization in one tower.

Cons: Higher capital cost; requires strict vacuum and temperature control.

Conclusion

Palm oil deacidification process is a crucial step in the palm oil refining process. It is performed to inhibit the growth of FFAs, which would otherwise compromise the palm oil’s quality and safety. As a professional edible oil processing machine manufacturer, we can customize a suitable palm oil refining process for you based on your needs and investment costs. If you need palm oil refining plant, you can contact us.