Category Archives: In Press

DECOLOURISATION OF PALM OIL MILL EFFLUENT (POME) TREATMENT TECHNOLOGIES: A REVIEW

Since last decade, global demand for edible oil is growing resulting in a remarkable increase in the areas under oil crop cultivation. The Malaysian palm oil industry is one of the largest palm oil producers in the world. In processing palm oil, high volume of liquid waste known as palm oil mill effluent (POME) is generated. The increasing demands of crude palm oil has resulted in the enormous increase of the number of palm oil mills in Malaysia contributing to large amount of POME. Currently, treatment technologies of POME gain a lot of attention in order to meet the standard discharge limits. The colour of POME, which previously was not an issue, is recently being highlighted and it will be incorporated in the regulation soon. Thus, this article provides review on colourants in POME and its possible decolourisation treatments. The possible decolourisation technologies that will be highlighted in this article are adsorption, coagulation and flocculation, membrane technology, microbial treatment, photocatalysis, etc. including their potential in POME colour removal efficiency.

SELECTION OF OIL PALM MALE PARENTS FOR OPTIMAL PLANTING DENSITY ESTIMATED FROM MATURE CROWN SURFACE

Our study on selecting pisifera male parents aims at determining yield per palm as well as the optimal planting density of the tenera offspring. The data pattern came from dura x pisifera testcrosses, planted at 135 and 160 palms ha-1 in North Sumatra, Indonesia from which the breeding values of 15 pisifera parents of Ghana origin are estimated. Optimal palm densities were assessed from the leaf surface at mature canopy, obtained from the product of number of green leaves with the (asymptotic) maximum leaf area (0.95 L-max), inferred from a logistic growth curve fitted through leaf area values versus palm age. The time to reach the optimum values ranged between 5.5 to 7.9 years after planting. Amount of light under the palms, measured by the vigor of Mucuna cover crop, scored 50 and 67 months after planting (cc-score), considerably varied among pisifera. The clear negative correlation between yield and cc-score reveals that male parents selected for yield during the early years of production may generate tenera offspring palms that are highly lightcompetitive later on. To circumvent this drawback, this study suggests to select pisifera parents for yield per hectare at optimal palm density instead of yield per palm.

INFLUENCE OF POLYGLYCEROL ESTER ADDITIVE ON PALM OIL FRACTIONATION IN RELATION TO THE CRYSTAL SIZE DISTRIBUTION

The effect of polyglycerol ester (PGEmix-8) additive on palm oil fractionation was studied at isothermal temperature of 24°C. Sampling was conducted at 20 min intervals to determine the solid fat content (SFC) of the slurries and the yield and compositions of the olein and stearin fractions. The peak of crystal size distribution was reduced from 100 μm to an average of 70 μm when 0.1% (w/w) to 0.5% (w/w) of PGEmix-8 were added in palm oil. The peak value was further reduced to 35 μm when 0.7% (w/w) additive was used. In spite of this, the SFC of the slurries remained unchanged during the isothermal crystallisation. These results show that PGEmix-8 had influenced the crystal size distribution without affecting the volume of the crystals formed. The fractionation results showed that olein yield increased about 3% to 6% but the triacylglycerol composition of the oleins were comparable with the control. An increase of saturation and a reduction of monounsaturation content in the stearin fractions were observed with increasing PGEmix-8 addition. These results implied that the increase in olein yield was due to less olein entrainment as a result of the more homogeneous and smaller crystals of the palm oil slurries.