Corn germ oil can not only be refined into nutrient-rich edible fats such as salad oil, cooking oil and margarine, but also can be used as high-end raw materials in the paint, paint and soap industries. The deoiled cake contains rich nutrients such as protein, and can be used to make nutritional supplements for a variety of foods. The fat content of corn germ is between 17% and 45%, which accounts for more than 80% of the total fat content of corn. Corn oil is also called corn oil and corn germ oil. It is a vegetable oil extracted from corn germ. It is mainly composed of unsaturated fatty acids. The content is as high as 80% to 85%, of which oleic acid accounts for 30% to 48%, and linoleic acid Accounted for 34%~56%, linoleic acid is an essential fatty acid of the human body. It is a component of human cells. It can be combined with cholesterol in the human body, showing fluidity and normal metabolism, and has the prevention and treatment of atherosclerosis and other cardiovascular diseases. Efficacy The sitosterol in corn oil has the effect of lowering cholesterol. Corn oil is also rich in vitamin E, which has antioxidant effect, can prevent and treat dry eye, night blindness, dermatitis, bronchiectasis and other functions, and has certain anti-cancer effects .
Corn oil processing equipment Degerming complete equipment
At present, most of the domestic alcohol industry corn embryo extraction adopts dry or semi-dry method, and wet embryo extraction is commonly used in the starch industry.
The semi-dry extraction process is as follows:
Process flow: corn → cleaning → moisturizing → crushing → screening → suction separation → gravity classification → rolling embryo → screening → germ
Process description: The corn is first transported to a vibrating cleaning sieve to remove impurities, and then metal impurities and stones are removed by a magnetic separator and a specific gravity stone remover. The impurity content in the blank after cleaning is less than 0.5%. After cleaning, the corn uses a water machine to add hot water or direct steam to the cleaned corn to perform water vapor treatment to make the corn husk and germ absorb water and expand, creating a gap between the corn and the kernel, which is beneficial to the separation of the husk, germ and endosperm. Use a crusher to crush the moistened corn. The embryo elasticity and toughness after moistening are particularly good, and it is not easy to break, while the endosperm is broken into 4-6 petals. Then, the residue and corn husk are separated by a plane rotary screen, and the germ and endosperm are separated by a gravity separator. Then the embryo is rolled with a embryo rolling machine, the embryo is squashed, and the endosperm is crushed, and then the flake embryo is separated through a flat rotary sieve.
Main equipment: vibrating cleaning screen, magnetic separator, specific gravity stone removal machine, water impregnator, crusher, plane rotary screen, gravity separator, embryo rolling machine, etc.
Corn germ pretreatment and pressing equipment
The starch content in corn germ is relatively high. During the oil production process, the seed coat (the main component is starch) will affect the oil yield and oil quality. Therefore, the pressing section must pay great attention to cleaning and try to separate the endosperm and the coat. .
The starch contained in the germ is easy to gelatinize when the material temperature is high. Therefore, the steaming and frying process has different steaming temperature and moisture requirements for the embryos of different purity. The embryos with low purity have higher starch content and higher material temperature. Should be lowered. For the embryos with high purity, the steaming temperature will increase with the increase of the purity of the embryos, and the squeezed water will decrease accordingly.
In general, screw presses are used for pressing. In order to ensure a higher oil yield, the pressure of the press must be increased. For small output press plants, there is generally no supporting leaching workshop, and the press uses a double screw press. The press can control the residual oil of the pressed cake to less than 6%. In large-volume oil press plants, the pressure of the press can be appropriately reduced, and the residual oil can be increased to the leaching workshop for leaching. Because the water content in the pressed cake is low, for the pressed cake that is sold directly without leaching, the water content should be adjusted to about 12% for safety reasons.
Process flow: corn germ → screening → winnowing → softening → rolling embryo → steaming and frying → pressing → dregs → filtering → crude oil
Process description: Corn germ is first sieved or winnowed to remove the seed coat from the raw materials as much as possible to ensure the purity of the material, and then magnetic metal fragments are removed by magnetic separation to protect the subsequent machinery and equipment.
The cleaned germ enters the softening equipment to adjust the moisture and temperature of the germ to reduce its toughness, and then pass the embryo rolling mill to break the germ to destroy the cell wall and facilitate oil production.
The corn germ after rolling embryo enters the steaming and frying pan to make the protein fully denatured and solidified, the oil droplets agglomerate, and the viscosity is reduced. After heat treatment, the temperature and moisture of the material are adjusted to facilitate squeezing. The temperature and moisture of the steaming and frying should be based on the embryo material. Controlled by the difference in purity.
The steamed corn germ flakes enter the screw oil press for squeezing. The squeezed oil is conveyed to the clear oil tank through the oil residue conveyor, and then filtered by the filter and transported to the crude oil tank for storage. The clear oil tank is equipped with slag dredging. The machine can realize the back squeezing of the oil residue, and the pressed cake is transported to the cake store through the conveyor to be leached in the leaching workshop or stored in the cake store.
Corn germ oil refining complete equipment
Crude corn oil is a deep red amber vegetable oil obtained by pressing or leaching corn germ. Crude corn oil contains phospholipids, sterols, tocopherols and other unsaponifiables, fatty acids, waxes, and a special smell. , The crude corn oil has a high impurity content and becomes turbid at low temperature and cannot be used directly. After refining, it can obtain corn refined oil with low cloud point, low melting point and stable storage, which meets the national standards.
Process flow: crude oil → degumming → decolorization → filtration → deoxygenation → heat exchange → heating → deacidification and deodorization → heat exchange → cooling → crystallization → crystal growth → filtration → refined oil
Process description: After the crude oil is preheated, add light alkali to make the gum and some free fatty acids in the oil form soapstock, and then separate the soapstock, then add hot salt water to the oil to wash, and separate the soap water. Degumming is completed by the same washing once or twice. The degummed oil enters the decolorization process, adds activated clay to decolorize in the decolorization tower, and then is pumped into the leaf filter for filtration. After polishing, the filtrate enters the next process. After the leaf filter is blown dry, the waste clay is discharged through vibration. The decolorized oil is pumped into the gas separator for vacuum deoxygenation, and then the oil is pumped into the oil—the oil heat exchanger and the deodorized oil are heat exchanged for preheating, and then enter the heater when heated to about 250 ℃ into the combined deacidification and deodorization tower in high vacuum Deacidification and deodorization are carried out in the state to maximize the removal of fatty acids, odors and other volatile substances in the oil. The fatty acid mixed steam is discharged from the top of the tower into the fatty acid trapping system and sold. The oil is drawn from the bottom and pumped into the heat exchanger to exchange heat with the oil to be deodorized, and then cooled to obtain the deodorized oil. The deodorized oil is cooled and crystallized in a crystallization tank and then transferred to the crystallization stage. The oil after crystallization and crystallization is pumped into a filter to separate wax and grease to obtain refined oil.
Main equipment: centrifuge (or oil refining pot), decolorization tower, leaf filter, bag filter, combined deacidification and deodorization tower, spiral plate heat exchanger, crystallization tank, dewaxing filter, etc.
Process characteristics: using physical refining technology, equipped with advanced combined deacidification and deodorization tower, high automation, low production cost, low loss, designed dewaxing and degreasing process, the quality of refined oil can reach national first-class standards.