The rice bran oil extrusion process is a method of increasing the yield and quality of rice bran oil by using an extruder machine. The extruder machine applies high temperature and pressure to the rice bran, which causes the oil cells to rupture and release more oil. The expanded rice bran also has lower residual oil and higher protein content, making it more suitable for animal feed or human consumption.
The rice bran oil expansion process can be divided into the following steps:
1. Cleaning: The rice bran is cleaned to remove impurities, such as dust, stones, metal particles, etc.
2. Conditioning: The rice bran is conditioned to adjust the moisture and temperature, which are important factors for the extrusion process.
3. Puffing (extrusion): The conditioned rice bran enters the rice bran expander and direct steam is injected. By the rotating of the main worm shaft, the materials are extruded, heated, sheared and kneaded, the temperature and pressure increases and the materials are extruded out.
4. Solvent extraction: The expanded rice bran is sent to a solvent extraction plant, where hexane or other organic solvents are used to extract the oil from the rice bran. The solvent is then recovered and recycled, and the crude rice bran oil is obtained.
5. Refining: The crude rice bran oil is refined to remove impurities, such as gums, free fatty acids, pigments, odors, etc. The refining process may include degumming, neutralization, bleaching, deodorization, and dewaxing.
The rice bran oil expansion process is a green and efficient way of producing high quality rice bran oil from rice by-products. Rice bran oil has many health benefits, such as lowering cholesterol, preventing cardiovascular diseases, improving skin health, etc. Rice bran oil is also widely used in cooking, cosmetics, pharmaceuticals, and biofuels industries.