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8114296 
Book/Book Chapter 
Processing technology of rice bran oil 
Chakrabarti, PP; Jala, RCR 
2019 
Elsevier 
Rice Bran and Rice Bran Oil: Chemistry, Processing and Utilization 
55-95 
English 
Rice bran oil (RBO) is not a seed-derived oil. Therefore, the crude oil obtained by conventional solvent extraction 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 refining 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. © 2019 AOCS Press. Published by Elsevier Inc. All rights reserved. 
Bleaching; Degumming; Deodorization/deacidification; Dewaxing; Micronutrients; Oryzanol; Physical refining; Stabilization