How to separate embryos? The separation of corn embryo mainly includes dry peeling and wet grinding. Raw materials are directly peeled for embryo milling without wetting water, which is also called dry peeling for embryo milling. Generally, it can be used when the grain moisture content is about 18%, but the processing loss is large; Wet grinding method is used to extract embryos and make flour, that is, the seeds are soaked and peeled. Its production process is (1) seed soaking: the selected seeds are soaked in sulfur dioxide solution for 40-60 hours. Soaking barrels are generally stainless steel barrels with a diameter of 5-6m and a height of12-15m.
(2) Crushing and embryo separation: the soaked corn kernels have softened and the tissue components are loose. After grinding or crushing, water is added to the embryo separation tank to make the embryo float on the water surface and separate the embryo. Using embryo separation tank is a kind of sample system technology in China, but the highest separation rate is only 85%, and the separation efficiency is low. Large processing plants outside Russia and China use cyclones for separation, and the embryo separation rate can reach over 95%.
1. Production process of corn germ oil pressing equipment: corn germ → cleaning → steaming and frying → pressing → filtering → crude germ oil → refining workshop.
Main equipment components: hoist, cleaning screen, steamer, oil press, filter, crude oil temporary storage box,
Second, the corn oil production process crude oil refining equipment crude oil-alkali refining-degumming-decoloring-deodorization-dewaxing workshop (or refined oil workshop)
Main equipment: refining tank, decoloring tank, deodorizing tank, heat conduction oil furnace, filter, etc.
The process of refining corn oil by pressing corn germ oil is to make oil by pressing. It is necessary to pay special attention to all key treatment links before pressing corn germ, as well as oil channel dredging and crude oil recovery during pressing, which can effectively improve the grain-oil ratio. The crude oil produced contains a certain amount of saturated fatty acids, lipids, waxes and cholesterol. Non-glyceride impurities such as free fatty acids, phospholipids, pigments and a small amount of protein colloidal substances. In addition, it also contains some pigments. Therefore, in order to obtain refined corn oil, it must be dewaxed, deacidified, decolorized and deodorized.
There are two kinds of pigments in corn crude oil: one is natural pigments, such as carotene, lutein, chlorophyll and other substances, which are easily adsorbed and decolored by bleached soil. The other is the pigment formed by the decomposition products of organic matter, which is brown and not easy to be adsorbed and decolored by bleaching soil. They are usually dispersed in oil in colloidal form. Although some pigments were removed during the processing, the increase was greater. Generally, the decoloring process of corn oil is as follows: the cross decoloring process of primary bleaching soil and secondary decoloring effect; If the rough is not handled in time and it is difficult to decolorize the crude oil with dark oil color, pre-decolorization can be used.
In addition to its original corn flavor, the decolorized corn oil also has the "soap" smell brought by alkali refining and the "fishy smell" brought by decolorization, which needs further deodorization to make the corn oil meet the flavor requirements.