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Oil palm fronds (OPF) are one of the main by-products of the oil palm industry in Malaysia. It contains about 38.5 % crude fibre with ME values of about 5.65 MJ/kg dry matter. OPF has great potential to be utilized as a roughage source or as a component in a complete feed for ruminant animals. This paper briefly reviews the availability of OPF in Malaysia and its importance in the local beef and dairy industry. About 26 million metric tonnes of OPF are produced on dry matter basis annually during pruning and replanting operations in the plantations. The nutritive value of OPF and studies to improve its feeding value is highlighted. The optimum level of inclusion for ruminant feeding is 30 % and improvement to intake and digestibility can be further enhanced with addition of other oil-palm by-products. Performances of beef and dairy cattle fed fresh OPF or as silage, pellets and cubes are shown. Good quality OPF silage can be produced without using any additive and the significant improvement on the rate of growth and milk yield were shown. With good formulations, OPF based diets can allow live weight gains of between 600-850 g/day and for local crossbred dairy animals, milk yield of about 11.1 to 20.3 liter/day can be obtained. Pellet based on ground OPF seemed to be less well utilized for ruminant feeding due to its smaller particle size. OPF based cubes which have longer particle size is more suitable for beef and dairy cattle. Long-term feeding of OPF based feeds have been shown to produce good quality carcasses, and the meat is safe for consumption.

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A thermo-separating aqueous two-phase system composed of Dehypon ® LS 54, a polymeric surfactant and the waxy maize starch (amylopectin starch) has been used for partitioning of cutinase as a model protein. Dehypon ® LS 54 were characterized by using 1 H NMR spectroscopy to get information regarding the chemical structure and to confirm the presence of aliphatic moiety group in this copolymer. The phase diagram obtained for these novel polymer-polymers two-phase system shows two-phases with high polymer concentration. The waxy maize starch is enriched in the bottom phase while the copolymer Dehypon ® LS 54 is found in the upper phase. Since this copolymer (Dehypon ® LS 54) is thermo-reactive, the upper phase can be removed and heated above the copolymer's cloud-point which resulting in the formation of a new two-phase system with a lower water phase, containing the target protein and an upper is copolymer-rich phase. Our results show that systems formed by waxy maize starch and Dehypon ® LS 54 could become an alternative system to be used in large scale protein and enzyme purification due to their low cost, and also because they offer a viable solution to problems of polymer removal and recycling which makes this system more attractive.

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The effect of microwave power density on the microwave drying of red pitaya (Hylocereus costaricensis) was investigated using a small modified commercial microwave. Microwave power density was varied in the range of 5.47 to 19.02 W/g. The ambient, internal sample and sample surface temperatures, and moisture loss were measured during microwave drying at various microwave power densities. The drying rate increased with increasing power density. The temperature profiles rapidly reached their saturation level. The experimental moisture loss data were fitted to the Tang and Cenkowski drying model using a value of residual sum of squares (RSS) to evaluate the goodness of fitting the model. The dried product was analysed to examine the quality such as color, shrinkage, tensile hardness and structure. The results showed that the color change is higher at higher power density and temperature because of the faster browning rate and faster drying rate. The beginning of the color change corresponded closely to the beginning of the falling rate period. The microwave drying also caused the red pitaya to shrink to a greater extent of up to 70% at higher power density because of the faster drying rate. The internal structure also tended to collapse during microwave drying.