After that, the fatty acid composition, bioactive compounds, and the processing technologies of rice bran oil are described and the refining technology of rice bran oil (degumming, deacidification, dewaxing, etc.) as well as the technologies to remaining the bioactive compounds in rice bran oil are introduced.
How to refine rice bran oil?
In industrial production, rice bran oil is mostly refined by hydration degumming, active clay decolorization, steam deacidification and deodorization, and low-temperature freezing dewaxing. The specific method is to add 2‰~3‰ phosphoric acid and a proper amount of water to treat the crude rice bran oil at 90 °C for degumming.
How is rice bran oil processed?
The crude rice bran oil must go through a series of refining processes before it can meet the requirements of the standard of edible oil; those refining processes include degumming, decolorizing, and deodorizing (Haraldsson 1983 ), these processing are briefly described as follows.
What is deacidification of rice bran oil?
Deacidification is the process of removing free fatty acids from crude rice bran oil. The deacidification methods of rice bran oil include alkali refining, distillation, mixing, re-esterification, and extraction. The alkali refining method has comprehensive effects such as deacidification and decolorization, but the refining loss is much higher.
Can rice bran be treated with enzymes?
Treating rice bran with enzymes is a new oil processing technology. In this technology, the cell tissue of rice bran is hydrolyzed with protease and then oil is released to achieve the purpose of oil extraction (Hanmoungjai et al. 2001 ).
How to dry rice bran?
The specific operation is to adjust the moisture content to 17%, then increase the temperature to 105 °C and heat with steaming for 2 h, and finally dry the rice bran. Hot steam treatment can slow down the hydrolysis of oil by inhibiting the activity of the enzyme.