First the husk of the rice grain is removed, resulting in a brown rice grain. The brown bran layer and rice germ are then removed leaving behind a white rice grain.
Rice Bran Oil is first extracted from the bran and germ. The oil is then refined and separated into a clear liquid and hard fraction. The clear liquid is extra cold filtered for maximum purity. The hard fraction is filtered and is used to make Alfa One Rice Bran Oil spread.
Rice bran is a byproduct of the rice milling process (the conversion of brown rice to white rice), and it contains various antioxidants that impart beneficial effects on human health.
Rice bran oil (RBO) is not a seed-derived oil. Therefore, the crude oil obtained by conventional rice bran oil solvent extraction machine using hexane has a number of impurities that are required to be removed before human consumption. Unlike other oils, the bran contains a lipase enzyme that converts the neutral oil to free fatty acids (FFAs) and partial glycerides. The bran has to be either stabilized or it has to be subjected to solvent extraction immediately after rice milling. However, the crude RBO will have higher FFA contents compared to other common vegetable oils. The use of alkali for neutralization may result in higher refining loss.
More importantly, RBO contains a number of minor constituents such as oryzanol, tocopherols, tocotrienols, squalene, phytosterols, steryl esters, etc. having proven health benefits. The major challenge for a processor is to keep most of these micronutrients intact in the refined oil. The addition of alkali reduces the micronutrient contents in refined oil. It is, therefore, evident that physical refining would be the preferred refining methodology for RBO. The major prerequisite for processing the oil through physical rice bran oil refining equipment is to have phosphorus content < 5 ppm for degummed, bleached, and dewaxed oil. Degumming is the key pretreatment process before physical refining, followed by bleaching and dewaxing. Because RBO is a dark-colored oil having waxes, special strategies are to be adopted even for bleaching and dewaxing. If proper care is taken during pretreatment steps, very good quality edible RBO can be produced using a well-maintained deodorization/deacidification unit.