The unit operations involved in palm oil processing include fruit sterilisation, fruit loosening/stripping, digestion, oil separation and clarification (Fig. 1). Fruit sterilisation is a heat rendering and moisture absorption process which inactivates the lipolytic enzymes in the fruit mesocarp tissue. The hydrolysis of the colloidal mucilage in the cell wall and the breakdown of carbohydrate molecules into glucose molecules initiates osmotic pressure in the cell. The pressure of the liquid fat assists in heat transmission of the cell walls. In mechanical processing of palm fruit, sterilisation enhances fruit recovery during fruit stripping and facilitates fruit digestion by softening the mesocarp tissue. Fruit loosening or stripping refers to the separation of fruits from bunches, quarters or spikelets. It is usually done to facilitate handling of fruits in subsequent operations. Fruit digestion means crushing and detachment of the steamed or heat-weakened mesocarp from fruit nuts. The main purpose of fruit digestion, which is a form of size reduction and wet comminution operation, is to break up the pulp of the fruit and liberate oil from the cells in which it is contained. The extent of the digestion of the fruit determines the degree of exposure of the oil cells. Thus, sterilisation and digestion operations are essential pre-treatment operations for palm fruit. Oil separation entails separating the crude oil from the mash, while clarification is the separation of pure oil from the sludge in boilers or clarification tanks.