The rice bran oil making process is a complex process that involves several steps, such as cleaning, conditioning, puffing, solvent extraction, refining, and dewaxing. Here is a brief overview of each step:
1. Cleaning: The raw material (rice bran) is cleaned to remove impurities, such as dust, stones, and metal particles.
2. Conditioning: The cleaned rice bran is heated and moistened to improve its physical properties and make it suitable for puffing.
3. Puffing: The conditioned rice bran is fed into an extrusion machine that applies high pressure and temperature to rupture the oil cells and increase the oil yield.
4. Solvent extraction: The puffed rice bran is sent to a solvent extraction plant, where hexane or other organic solvents are used to extract the oil from the bran. The solvent is then evaporated and recovered, leaving behind crude rice bran oil and defatted rice bran.
5. Refining: The crude rice bran oil is refined to remove impurities, such as free fatty acids, phospholipids, pigments, and odors. The refining process usually includes filtering, neutralization, degumming, decolorization, and deodorization.
6. Dewaxing: The refined rice bran oil is dewaxed to remove the wax content that may cause cloudiness or crystallization at low temperatures. The dewaxing process usually involves cooling, crystallizing, and filtering the oil.
This is how rice bran oil is made from rice bran.