Full Refining

Full refining is an important step in improving the quality of oil. It has a great effect on removing impurities from oil, lowering the smoke point, and extending storage time. In addition, it can also remove the odor of raw materials and lighten the color of oil.

1.Hydration and degumming

Hydration degumming uses the hydrophilic groups contained in lipid molecules such as phospholipids to add the required amount of hot water or dilute acid, alkali, salt and other electrolyte aqueous solutions to the oil, causing the colloidal impurities to absorb water, expand and condense, and remove the oil from the oil. It will settle out and separate from the oil. Degumming process: filter crude oil → preheat → add water to hydrate → leave to settle (heat preservation) → separate → hydrate the oil → add water to dehydrate → degumming → crude phospholipid oil foot → recover neutral → crude phospholipid

2.Deacidification (alkali refining)

Deacidification is by adding alkali to neutralize the free fatty acids in the oil to generate fatty acid salts (soap) and water. The soap absorbs some impurities and settles and separates from the oil.

3. Adsorption and decolorization

Adsorption decolorization is to add certain surface-active substances with strong adsorption capacity into oil, and under the required process conditions, adsorb pigments and other impurities in oil. Through filtration, adsorbents and impurities are removed to achieve the purpose of oil decolorization and purification. Decolorization is one of the important processes in edible oil refining. In addition to removing pigments from oil, it can also reduce the phospholipid content, peroxide value, soap content and metal ion content, thereby improving the color, flavor and oxidative stability of the oil, and providing good conditions for further refining equipment. At present, the most commonly used method for oil decolorization is activated clay adsorption decolorization, which uses clay, a substance with strong selective adsorption power, to remove pigments and other impurities dissolved in oil under certain conditions.

4. Vacuum steam deodorization

Vacuum steam deodorization is a deodorization method that is widely used at home and abroad and has good effects. There is a big difference in the volatility of the odorous substances in the oil and triglycerides. Under high temperature and high vacuum conditions, the principle of steam distillation is used to make the volatile substances that cause odor in the oil mix with the water vapor in the deodorizer. Escape together to achieve the purpose of deodorization.