AbstractPalm oil is obtained from the fruit flesh ofElaeas guineensis. Whole bunches of ripe fruit are harvested and brought to the oil mill. Processing involves sterilization, mechanical removal of fruit from the bunch, and mechanical breakdown of the fruit structure followed by expression of the oil in a screw press. Oil mixed with water and fruit debris is purified in settling tanks and centrifuges, dried and stored. Oil yield represents 22% of the fresh fruit bunch and kernels a further 5%. The solid wastes are the empty fruit bunch, the press fiber and the nut shells. Empty bunches are incinerated, while fiber and shell are used to fire the mill boilers. The liquid effluents are mixed and usually treated by anaerobic/aerobic fermentation until fit for discharge. Various treatment systems are described. Quality control in the oil mill concentrates on (a) minimizing deterioration of the oil by hydrolysis and by oxidation, and (b) optimizing oil yield by frequent measurements of oil losses.