In conventional extraction of palm oil, a substantial loss of product occurs in the stages of the fruit pressing and clarification of the "crude" oil. The high viscosity of "crude" oil is the main factor that affects the separation of the oil from the other components in the mixture. This is usually overcome by the addition of water in the clarification stage. This work addresses the study of the influence of dilution and enzymatic treatments on the rheological behaviour of crude oil. Data obtained were found to be useful for determining the separation velocities in the clarification and centrifugation stages. The palm oil employed in this work was supplied by a commercial plant and had the following composition: water (65%), oil (30%) and solids (5%). This feed was enzymatically hydrolysed at 60°C using a commercial enzyme (viscozyme) and a laboratory enzyme preparation. For a fix shear rate of 6s-1, the enzymatic treatment decreased the viscosity in about 29 % while with the addition of 20% of water the viscosity reduction was 35%. The combined effect of enzymatic and dilution treatments leads to viscosity reduction of 75 % approximately.
