Free Fatty Acid in crude rice bran oil is removed by neutralize the oil with caustic soda and become soapstock. In the same time, gamma Oryzanol, Tocopherol, Tocotrienol and some color pigment also been removed from rice bran oil. Refined rice bran oil from this process has lighter colour, less gamma-Oryzanol, less Tocopherol, less Tocotrienol.

With this process, Free Fatty Acid in crude rice bran oil is removed by heat and vacuum in De-Acid process and let most of gamma Oryzanol, Tocopherol and Tocotrienol remain in rice bran oil.