Removal of free fatty acids, gums, color pigments and oxidizing particles via centrifugal separation, after reaction with lye, followed by water washing and separation of residual soap.
Removal of color pigments, oxidized components and residual gums via absorption in bleaching clay or other adsorbents, followed by separation of the spent absorbent.
Removal and recovery of residual free fatty acids and other volatile impurities via vacuum steam distillation. The heat treatment also produces a bleaching effect.
In case of ghee manufacturing, soft oil is converted to hard oil, to obtain semi sold texture. In this process, hydrogen gas is passed through the oil, till required melting point ( 36 ± 2).