There are two production processes of sunflower oil: pressing process and leaching and refining process.
1. Production process of sunflower oil pressing
The pressing process of sunflower oil retained many beneficial nutrients such as polyunsaturated fatty acids, protein, dietary fiber, vitamins and trace elements in the oil.
Production process of sunflower oil pressing:
Cleaning → shell peeling → embryo rolling → steam frying → pre-pressing → pressing
Production process of sunflower oil pressing
1. Cleaning: use cleaning screen and stone removal machine to remove impurities such as iron chips, stones, grass and soil in sunflower seeds.
2. Shell peeling: Use shell peeling machine to remove the shell of sunflower seeds. On the one hand, it can avoid sunflower seed shell absorbing oil to reduce oil loss. On the other hand, it can also avoid sunflower seed shell affecting the operation of equipment and damaging the equipment.
3. Embryo rolling: the shelled sunflower seeds are transported into the embryo rolling machine for embryo rolling. Embryo rolling is the process by which sunflower seeds are rolled into thin slices to destroy tissue and make it easier for oil to flow out.
4. Steam frying: Steam frying can adjust the temperature, humidity and internal structure of sunflower seeds, so that oil can be better produced during pressing. The common equipment for steaming and frying is a wok.
5. Pre-pressing: the roasted sunflower seeds are first sent to the pre-pressing machine for pressing, and a part of the oil is extracted first, which can improve the yield of sunflower oil. The oil content of the pre-pressed sunflower cake is 15%, and then it is pressed again.
6. Pressing: The equipment used in pressing is the press. The residual oil percentage of sunflower seed cake after pressing is about 6%.
The pressed sunflower oil conforms to the national standard and can be used.
1. Degumming section
The insoluble impurities in sunflower oil not only affect the stability of oil, but also affect the refining and advanced processing of oil. The method used in the actual refining degumming process is hydration degumming. Hydration degumming is to add hot water to oil so that the gel soluble impurities absorb water, condense and separate from the oil.
2. Deacidification section
The deacidification section is mainly used to remove free fatty acids from sunflower oil. There are always some free fatty acids in oils, the amount of which depends on the quality of the oil. The common method of acid removal is alkali refining. The alkali fluid can neutralize the free fatty acids in sunflower oil, and the sodium salt generated is not easy to dissolve in the oil, and becomes flocculent and settles. Therefore, alkali refining has the comprehensive effect of deacidification, degumming, removing solid impurities and depigmentation.
3. Decolorization section
The pigment components in sunflower oil are complex and adsorption decolorization is commonly used for sunflower oil decolorization. Our common adsorbent is active white soil. The principle of adsorption and decolorization method is to use the adsorbent with strong adsorption ability to absorb pigments and other impurities in hot oil, so as to achieve the purpose of decolorization and purification.
4. Deodorization section
Sunflower oil by deacidification, decolorization treatment will also have trace aldehydes, ketones, hydrocarbons, white soil, residual solvent odor, etc., remove these odor process is called deodorization section. When deodorizing, it is necessary to first pass high temperature direct steam into the oil, and use the volatile difference between the oil and the odor substance to remove these substances, so as to complete deodorization.
5. Dewaxing section
The wax in sunflower oil will affect the flavor and taste of the oil, so it needs to be dewaxed. At present, the production of edible oil basically adopts freezing crystallization method. The specific dewaxing process operation also needs to be set according to the wax content of sunflower oil and market requirements. After dewaxing, first-class sunflower oil can be obtained in line with national standards.