| With corn oil samples including crude oil, degummed oil, dewaxed oil, bleached oil and deodorized oil from production line of super degumming combined with pre-bleaching-re-bleaching, deodorization and deacidfication using twin towers as research subjects, the contents of free fatty acid, phosphorus, metal ions, pigment and tocopherol, and peroxide value were determined in order to investigate the effects of refining process on trace components in corn oil. The results showed that free fatty acid content decreased obviously after deodorization and deacidification using twin towers. About 95% phospholipids were removed after super degumming. The contents of metal ions decreased obviously after degumming and bleaching. Most pigment was removed after bleaching. After deodorization, 19.9% tocopherol was lost. The peroxide value increased after degumming, but it significantly decreased after deodorization and bleaching. Therefore, suitable refining process should be selected according to the quality of crude oil. In this way, benefit minor compounds could be reserved, simultaneously, harmful minor compounds were removed, and moderate refining was achieved. |
