Keyword : bleaching, colour

The term bleaching refers to the process in which the colour of the oil is reduced by removal of the colour producing substances – i.e. pigments. Bleaching is part of the refining process and involves in part the adsorption of colour producing materials on an adsorbent material called bleaching earth. Usually, bleaching earth does not remove all the colour producing materials, much of which are actually removed by thermal destruction during the deodorization process.