Abstract
Currently, a majority of vegetable oil is extracted from various oil-bearing materials by either hexane extraction or a process that combines pressing and hexane extraction. In terms of the safety and environmental issues, an expectation for developing an alternative process of hexane extraction gets bigger as time goes by. Full pressing and supercritical carbon dioxide extraction have already been applied for a small scale production. Enzymatic aqueous extraction is also investigated. But these alternative processes are not relevant for a large scale production of commodity oils, such as soybean, canola and so on. Further studies to increase oil yield and reduce operational cost are required.
On the other hand, enzymatic degumming becomes widespread elsewhere in the world. Enzymatic degumming is based on conversion of non-hydratable phospholipids to hydratable lyso-phospholipids which are easily removed from crude oil to the water phase by centrifugation. As enzymatic degummed oil can be refined by physical refining, this process is advantageous to low cost and environment-conscious operation in comparison with chemical refining.
