Contaminants (impurities), such as phosphatides, free fatty acids (FFA) and antioxidants, etc., should be removed prior to consumption of industrial use and edible oils. This is the unit from which impurities are removed. Edible liquids and fats should be completely refined to improve their color, taste, smell and long-term use. Industrial (industrial) use oils can be refined in whole or in part to remove undesirable components which will affect the quality of the final product.
Two processes have been developed to refine edible oils. These are physical and chemical refining processes. The decision on the choice of these processes depends on the type and quality of the crude oil to be processed. The name of physical and chemical refining processes comes from process technologies used to remove free fatty acids (FFA) that cause acidity of the oil. Physical refinement is a process performed using the lower boiling point of free fatty acids compared to the boiling point of triglycerides. In the chemical or alkali refining process, an alkali free fatty acids (FFA) is used to neutralize the labor. The main purpose of the chemical refining process is to saponify the free fatty acids (FFA) with the aid of an alkali solution and to dilute the soap in the water phase. These soaps are removed by the seperators. While static separation processes are used in low-capacity cut-off processes, centrifugal processes are used in continuous and high-capacity processes. The neutral oil is dried, bleached, vintered and deodorized, respectively. This chemical refining process is used in the refining process of almost all crude oils.
The aim of the modern machine rafting process is to remove undesirable impurities in the oil in such a way that the glycerides are least harmful, keeping the desired components at minimum loss.
The refinery unit is a combination of the following process steps;
- Gam Removal is the removal of gums and phosphatides from crude oil.
- Neutralization is the removal of crude oils, water-insoluble hydrates, all phosphatides and free fatty acids, in short saponifying substances.
- Bleaching is the removal of soap, metal and coloring pigments from crude oil.
- Vinterisation is the removal of components with melting point at high temperature.
- Deodorization is the removal of volatile impurities from free fatty acids remaining in neutralized and bleached oils, all free fatty acids in physical refining, oils that affect the taste and odor (especially ketones and aldehydes).