Can rice bran oil be pressed? The answer is yes, but there are conditions. First, the purity of rice bran should be high, preferably rice bran obtained after separation of bran. If mixed with broken rice, a large amount of starch in the broken rice will gelatinize and become sticky during steaming, and the oil yield will be greatly reduced during pressing. ; Second, the raw materials must be fresh, because rice bran is easy to go rancid, and the quality of the oil squeezed out of rancid rice bran is relatively poor; third, steaming and frying equipment needs to be added, because if pressed directly, the rice bran will easily stick to the snails of the oil press, affects the oil yield, and is also difficult to clean later. If the above conditions can be achieved, rice bran can be pressed to produce oil. Below, Huatai Oil Machinery will briefly introduce to you the rice bran oil pressing process.
Rice bran oil pressing process:
Separation of bran–obtaining pure rice bran–mixing rice husk–adding water–steaming embryo–frying embryo–pressing–raw rice bran oil
1. Separation of bran
As mentioned in the first paragraph, the purpose of bran separation is to remove broken rice and impurities in rice bran to ensure the oil yield. Generally, a small square sieve for bran separation is used for screening. If it is a rice bran oil pressing workshop with a small output, it is best to buy pure rice bran, so that there is no need to buy a bran separation screen.
2. Mixed with rice husk
Mixing 4.5% to 5% shell into rice bran can increase the hardness of the billet. When steaming the billet, the steam can easily pass through and the billet will be evenly ventilated. After adding the rice husk, stir evenly.
3. Add water
When steaming, water should be added appropriately to make it easier to get air. When the moisture content of rice bran is 11% to 12%, 20% water is generally added. Add water evenly to make the rice bran looser.
4. Steaming embryo
The purpose of steaming rice bran is to soften the crude fiber in the rice bran, condense the protein, rupture the cells, and aggregate the small oil droplets into larger oil droplets, making it easier to squeeze out the oil.
5. Frying embryo
The function of frying the embryo is to reduce the moisture content so that the moisture and temperature of the embryo meet the requirements for pressing.
When the embryo is transported into the rice bran oil pressing equipment, the temperature should be maintained between 80°C and 90°C. When starting up the machine for the first time, feed the material slowly. After the press chamber is heated, gradually increase the feed amount. When pressing, the slag between the gaps between the pressing bars should be mixed into the material blank at any time for re-pressing.
The rice bran crude oil obtained by pressing must also enter the refining workshop for refining and dewaxing. The pressed cake still contains 6-7% residual oil. If the amount of raw materials is small, this part of the oil can be ignored. However, if the daily processing is more than 30 tons, a lot of oil will be lost using the pressing method. Our engineers from Huatai Oil Machinery recommended to use the puffing-extraction method to produce rice bran oil, and the residual oil rate can be controlled below 1%. Whether you want to produce pressed rice bran oil or extracted rice bran oil, you can contact us. Our engineers can customize the process and equipment for you according to your specific needs.