Sunflower seed temperature-controlled oil press

Sunflower seed temperature-controlled oil press

Sunflower seeds have a high oil content, ranging from 38% to 45%. Sunflower oil is often extracted by pressing in industrial production. The crude oil obtained by pressing is light in colour and has a faint aroma of sunflower seeds. The subsequent refining process is simple and the finished oil can be used either for frying or for cold mixing.

Regarding the sunflower seed processing and extraction process:
Sunflower seed oil material - pretreatment - shelling - softening - embryo pressing - steaming - pressing - filtering - refining - finished sunflower seed oil
Common oil pre-treatment processes include sieving, air separation, magnetic separation, water separation and side-by-side slurry cleaning. The different physical properties of the oil and impurities are used to separate solid impurities. Sieving, air separation and magnetic separation are commonly used for sunflower oil cleaning. Sieving separates solid impurities from the oil through sieve holes based on the difference in width, thickness and length between the oil and impurities; wind separation separates light impurities and dust, as well as some stones and earth, using the difference in suspension speed between the oil and impurities; and magnetic separation separates magnetic metal impurities from the oil using magnetic force.

As sunflower seed hulls contain no oil and a small amount of vegetable wax, in practice, the requirement is that the sunflower seed hull content should be less than 10%. To achieve a good oil yield, sunflower seeds need to be softened, pressed and steamed before pressing, after being cleaned and de-hulled. Softening is to regulate the moisture and temperature of sunflower seeds, to improve the plasticity of the oil and to achieve a good embryo pressing effect, so as to avoid too much powder during embryo pressing.
Embryo pressing is to process the granular oil into thin slices by mechanical equipment, so as to fully destroy the oil molecules and create good conditions for steaming and frying. Steaming and frying is an important pretreatment for sunflower seed pressing. The temperature at which sunflower seeds are steamed and fried directly affects the flavour, colour and quality of sunflower oil. When the temperature of the frying pan is low, the aroma of sunflower oil is light. As the temperature rises, the aroma becomes more intense. However, when the temperature reaches a critical value, a burnt smell appears, affecting the flavour of the sunflower oil.
The colour of the pressed oil also gradually deepens as the pressing temperature rises. The acid value, peroxide value and vitamin E of sunflower oil will change to varying degrees. We recommend that the steaming temperature of sunflower seeds is controlled during the steaming and frying stage to provide good conditions for the later pressing and to ensure the quality of the oil produced. Sunflower oil is mainly pressed by a screw press. The screw press is a dynamic press. The screw shaft rotates continuously in the press cage by means of a power transmission to supply the oil to the press embryo.
During the rotation of the screw press, the threads continuously push the oil forward, the space in the pressing cavity is squeezed and the material layer on the surface of the screw rotates together with the press shaft. The oil is not only pressed forward in the press cavity, but there is also a great deal of frictional resistance between the embryo and the screw press, and between the embryo and the press cavity. The temperature generated by the friction supplies heat to the oil press equipment, resulting in the denaturation of the proteins in the embryo, a reduction in the viscosity of the oil and the separation of the oil from it to achieve the desired oil yield. The crude oil flows out of the round and strip row gaps and the solid impurities in the crude oil are separated by a centrifugal filter and transported to the gross oil tank for refining. After refining the crude oil can be transported directly to the market for sale.

In the process of sunflower seed oil extraction, the good or bad oil press equipment directly affects the production efficiency of the oil mill. Choosing a reliable oil press equipment can get twice the result with half the effort. Ltd. has been focusing on the production of grain and oil machinery and equipment for more than 40 years, and has been dedicated to the research and development of oil press machinery and equipment production technology, manufacturing screw oil presses that can achieve automatic heating, adjustment, transmission and vacuum filtration.