The removal of minor components through adsorptive bleaching is based on several adsorption mechanisms (Gibon et al., 2007). Part of the coloring pigments (carotenoids in the case of palm oil) are physically adsorbed on the bleaching clays, involving “Van der Waals” surface attraction forces; other components are chemically bound to the bleaching clay surface via covalent or ionic bonds or removed through molecular entrapment in the porous structure of the clays. Some minor components are also chemically altered due to the catalytic activity of the clays