The process of making rice bran oil involves several steps. Here is a brief overview:
Rice Bran Preparation: The raw material, rice bran, is prepared thoroughly. This includes screening and heating the rice bran using steam at a temperature greater than 100°C to inhibit Lipase hydrolysis before extraction.
Rice Bran Oil Expelling: The well-prepared rice bran is put into the feeder of the expeller, where a screw worm transports the rice bran forward. As the screw worm moves, the space becomes smaller, squeezing out the rice bran oil.
Rice Bran Oil Extraction: After collecting the rice bran oil cake, the oil extraction process begins with the help of a food-grade solvent, usually hexane1. This process works on the principle of counter-current and moving bed with variable bed height and different speed mechanisms to ensure excellent penetration and percolation of solvent for absolute extraction.
Rice Bran Oil Refining: The crude rice bran oil is then processed in a refining process that includes filtering, neutralization, degumming, decolorization, deodorization, and dewaxing1. After all these processes, fresh rice bran oil is ready.
It’s important to note that rice bran must be processed into oil within 48 hours of being separated from chaff in order to be fit for human consumption. However, the exact time it takes to produce rice bran oil can vary depending on the specific methods and equipment used.