The Effect of Microwave Treatment on Physical Properties of Oil Palm Trunk (Elaeis guineensis)

Oil palm tree is one of the largest plantation crops in Malaysia, generating abundance of agricultural waste every year. Currently, supplies of wood are becoming limited, and the oil palm trunk could be the potential alternative source to replace wood. However, in spite of its many uses, oil palm trunks consist of very high moisture content. Freshly felled oil palm trunk has a wide range from 100-500% moisture content. This study is aimed to observe the effect of microwave treatment on the physical properties of oil palm trunks. Only the basal portion was used in order to reduce variability of sampling. Microwave treatment of the oil palm trunk samples were conducted by using a domestic microwave oven operating at 2.45 GHz and with maximum rated power output of 1000 watt. The samples were microwave-treated at four different power intensities of 100%, 80%, 60% and 40% and for four different exposure durations of 5, 10, 15 and 20 min leading to a total six varying combinations of power and exposure period. The untreated oil palm trunk sample was used for comparison purpose. Enhancing the drying conditions using microwave, avoiding burning, shrinkage and increasing the density of the oil palm trunk is aimed to develop a new value-added material. The study evaluates the moisture content reduction and density reduction of the microwave-treated oil palm trunk. From the result, there is clear indication that the microwave treatment significantly reduced the moisture content. There is also clear indication of density reduction after being subjected to microwave treatment in comparison to the untreated samples.