1. Clean up. The germs recovered from corn dumplings are often mixed with corn flour and crumbs, which should be cleaned up by double-layer vibrating screen. Screen mesh, 1.5 meshes in the first layer and 4 meshes in the second layer. If there are more embryonic debris under the sieve, 5-mesh or 7-mesh sieve can be used to reduce bud loss. The recovered germ of corn starch is mixed with the cuticle radicle crumbs. It is washed and removed continuously in clean water by shallow dish or flume.
2. Drying. The recovered maize germ is easy to deteriorate and rancidity due to its high moisture content after cleaning. Therefore, it is necessary to dry the cleaned corn germ until the moisture content is less than 10%.
3. Rolling embryo. The dried maize germ is then rolled into 0.3-0.4 mm flake embryo by roller mill, which destroys the cell structure and facilitates steaming and pressing.
4. Stir-fry. The embryos are stir-fried in a steamer for 40-50 minutes until they gradually turn brown-red and start immediately when they can smell the fragrance. Be careful not to smell burnt. At this time, the temperature of the embryo is about 115 - 120 degrees Celsius, and the moisture content is between 2% and 4%.
5. Pressing. The steamed and fried embryos are directly put into the corn germ oil press
to press the oil. In operation, the initial feed is less. When the corn germ oil press operates normally, it feeds evenly, and discharges oil and cake. The normal operation of the corn germ oil press, its speed of oil pressing is 8 revolutions per minute. The residence time of embryo in the chamber was 2.5 minutes. The thickness of the tablets is about 5-6 mm. The oil yield is generally in the range of 22%-28%. The residual oil rate in the cake is 5%-6%. The extracted corn germ oil is commonly known as "crude oil" without refinement. " High quality corn germ oil can be obtained from crude oil by hydration, alkali refining and deodorization.