Heycarbons Activated Carbon For Edible Oil

Learn more about edible oil decolorization:

Application of wood powder activated carbon in vegetable oils:

The main component of oil is fatty acid glyceride, which also contains a small amount of free fatty acids and other impurities. The type and quantity of impurities are affected by the raw materials of oil, so the refining methods of oil are different.

Impurities are the products of metabolism of animals and plants in the life process, which are of great significance to their life activities, especially antioxidant impurities, which can prevent oil from oxidation and rancidity. Oil refining removes harmful components and retains beneficial components.

Usually, the refining method has three steps, namely neutralization, decolorization and deodorization. Neutralization generally uses sodium hydroxide to remove free fatty acids, and also has the function of removing proteins and colloids, and reducing the color. To make the oil light in color, further treatment is required. The treatment method can be through the action of chemical agents, but the common use is to use adsorbents.

Activated clay and activated carbon are indispensable adsorbents in the oil industry. White clay mainly plays a decolorizing role, while activated carbon mainly deodorizes, removes odors and decolorizes.

The selection of activated carbon type is also very important. Activated carbon products made by different activation methods have different performances and are suitable for decolorization of different oil products. It is better to test them before use. The pH value of activated carbon is crucial. Too much alkalinity or acidity can cause adverse changes in oil products. Heycarbons will recommend the appropriate pH according to the customer’s oil situation.

1. Coconut oil

The variegated color and impurities of coconut oil can be well refined by using activated carbon without mixing with other materials. For general coconut oil, the addition of activated carbon is less than 1% to obtain a good refining effect; but for crude oil of poor quality, the addition of activated carbon needs to be increased. The selection of activated carbon type is crucial. Different activated carbon varieties have a significant effect on the effect of decolorization and impurity removal. 

2. Cottonseed oil

Cottonseed oil has a complex composition, containing gossypol, various sugars, resins, lutein, chlorophyll, etc., so white clay and activated carbon need to be used in combination to achieve satisfactory treatment results. The ratio of activated carbon to clay is generally 1:(4~5), depending on the quality of the oil. Clay can remove yellow pigments, and activated carbon removes red and green, and the two have complementary advantages.

Activated carbon can also eliminate the earthy smell caused by the use of clay, and can also remove very trace substances such as saponins, phospholipids, colloids, etc. In the process of cottonseed oil treatment, it is not advisable to use acidic clay because it is easy to decompose oils and has the effect of promoting oxidation.

3. Peanut oil

General peanut oil is of relatively good quality, and only activated carbon decolorization is required to achieve the effect. If it is dark peanut oil, clay and activated carbon need to be used together to achieve good results.

4. Soybean oil

Soybean oil can be used for both food and paint. When used for food, in addition to using an adsorbent with a high ratio of activated carbon to clay, the other methods are similar to those for cottonseed oil treatment, especially when the oil is very dark green. Activated carbon can remove substances that can produce bad odors in finished oil.

5. Olive oil

Due to the different pressing and extraction processes, the quality of olive oil is also different. High-quality olive oil, especially the olive oil obtained from the first pressing, does not need to be bleached. Low-quality olive oil can be treated with a mixture of white clay and activated carbon.

Olive oil obtained by carbon disulfide extraction often has a dark green color, which can be improved by treating with a mixture of white clay and activated carbon adsorbent to make it a golden product.

6. Corn oil

Corn oil can be treated with a mixture of white clay and activated carbon, but the proportion of activated carbon needs to be less than that of other oils. Some people believe that it should be treated under partial vacuum and at a temperature of 80°C or lower.

7. Hemp oil 

PH: The surface charge and pore structure of activated carbon may change under different pH values, thus affecting its adsorption capacity. Generally speaking, activated carbon has better adsorption effect under neutral or weakly acidic conditions (pH 5-7).

Temperature control:

The control of temperature during the decolorization process is very important. Too high temperature may cause the adsorption capacity of activated carbon to decrease, while too low temperature may slow down the decolorization process. It is generally recommended to operate within the range of 40-60℃.

Agitation and contact time:

Sufficient stirring helps to increase the contact area between activated carbon and oil, thereby improving the decolorization effect. The contact time also needs to be reasonably controlled, usually between 30-60 minutes, adjusted according to specific circumstances.

8. Soybean Oil

Decolorization: Powdered activated carbon has a huge specific surface area and rich pore structure, which can effectively adsorb pigments in soybean oil, such as chlorophyll and carotenoids, to achieve the purpose of decolorization.

Removing odor: Activated carbon can adsorb odor molecules absorbed during storage and transportation in soybean oil, improving the flavor of the oil.

Removing impurities: Powdered activated carbon can also remove harmful impurities such as polycyclic aromatic hydrocarbons and pesticide residues in soybean oil, improving the safety and quality of oil products.

These uses effectively improve the appearance, flavor and safety of soybean oil, making it more suitable for market demand.