Category Archives: 2005 Vol 17 June

Studies to improve the low temperature performance of palm oil products

The objectives of this research were to find some additives suitable for reducing the pour points and cloud points of palm oil products and hence, improve their low temperature performance. All the additives used showed satisfactory results, with greater reduction in the pour points and cloud points in POME, PKOME, POMEPOo, POMESOo and PKOMESOo. The biggest depression in pour point was about 7.5ºC (addition of 1.0% DHFA to POMEPOo) and the biggest reduction in cloud point about 10.5ºC (addition of 1.0% DHFA and 1.0% PP to POME).

Enhancement of cold stability of palm oil methyl esters

As with palm oil, palm oil methyl esters (POME) have poor cold stability. This drawback has limited their use in low temperatures. The objectives of this research were to identify some additives suitable for reducing the pour point and cloud point of POME to improve its low temperature performance. Of the additives used, EP produced the most promising results. The biggest reduction in pour point was about 15.0ºC (addition of 2% EP to POME) while the biggest depression in cloud point was about 6.4ºC (addition of 4% EP to POME).

Stress development and its detection in young oil palms in North Kedah, Malaysia

Various methods of detecting and quantifying stress in oil palm are briefly reviewed. Stress is defined loosely as any environmental condition leading to reduced productivity and loss of yield. Common environmental stresses include those induced by water deficit, water logging, low atmospheric humidity, high temperatures, nutrient deficiency and low radiation. Different stress-inducing factors are frequently combined; e.g. water deficit and high temperature stress, water deficit and nutrient stress; high temperature and low atmospheric humidity stress. Results are presented of measurements made on young field palms planted in a dry region in north Kedah, Malaysia. The measurement period spanned wet and dry seasons. Short-term stress responses evaluated were: i) changes in canopy surface temperatures relative to air temperatures, ii) changes in spear leaf extension rates, and iii) changes in the ratio of actual to potential evapotranspiration. The responses are related to soil water supply, solar radiation, atmospheric vapour pressure deficit and potential evapotranspiration rate. The potential for using canopy surface-air temperature difference ( ΔT) and spear leaf extension measurements as a means to monitor irrigation need is discussed.

Modelling seasonal variation in oil palm bunch production using a spreadsheet programme

Annual cycling in oil palm bunch yield is an almost invariable phenomenon even in regions that lack marked seasonal changes in climatic factors, such as radiation or rainfall, likely to have a large influence on yield. Furthermore, such cycles persist even under irrigated conditions. While yield-based endogenous feedback mechanisms have been invoked to partly account for such behaviour, the likely time-lags involved are not generally consistent with the regular annual cycles that are frequently observed. Using data obtained from a long-term trial on a peat soil with a good year-round water supply, the role of various developmental factors in contributing to the resultant yield patterns, was examined. The factors were: a) frond emergence interval (FEI), b) rate of inflorescence and bunch development (FEBR; defined by the number of days from frond emergence to bunch ripening), c) the proportion of nodes with bunches (NWB; mainly a function of sex ratio and abortion incidence) and d) single bunch weight (SBW). Frond emergence, male and female inflorescence numbers, abortion and single bunch weight all exhibited regular annual variation in the trial. Yields were simulated using a spreadsheet with the aim of dissecting out the contribution and relative significance of each factor. Even with all factors held constant, there was variation in monthly yield, although it was erratic and failed to result in the single annual peak characteristic of observed yield patterns. Regular annual peaks were, however, obtained by introducing sinusoidal oscillations in the amplitudes of the four factors either individually or in combination. Amplitudes were tested that represented a range of probable behaviour from mild to maximum variation. The best agreement between simulated and observed yields over an 8.5-year period (r2 =0.6) was obtained by varying NWB (using an amplitude of 50%) while similarly good agreements were achieved by appropriate variations in FEI and in FEBR. SBW had only a small effect. Combining factors did not appreciably improve the correlations over those obtained by the factors individually, although in some cases it resulted in similarly high correlations being achieved using lower amplitudes. These findings show that all the developmental processes examined played some role in accounting for annual yield cycles but the results still leave open the question of what factor(s) are responsible for the cycling of each of the underlying processes.

A study on thermal characteristics of phase change material (PCM) in gypsum board for building application

Using fatty acids as phase change materials (PCMs), it is possible to store a large amount of thermal energy in a small mass and with a narrow temperature transition. Passive solar heating and cooling can be done by three methods – simple immersion, direct incorporation and encapsulation. This study investigated the effect of using a lauric-stearic acids eutectic mixture at 75.5:24.5 w/w as PCM in gypsum board. The eutectic mixture had a melting point of 34.1ºC and latent heat of 171.1 kJ kg-1 respectively. Gypsum boards were immersed 1 hr in PCM and the thermal characteristics before and after immersion were investigated. The 12.5 mm board absorbed 38.0% PCM and differential scanning calorimetry (DSC) showed that the melting point and latent heat were 34.0ºC and 50.28 kJ kg-1 , respectively. For 6 mm board, PCM absorption was 39.2% with the melting point of 34.0ºC and the latent heat of 52.87 kJ kg-1 . From the results, the thermal characteristics of the PCM-gypsum boards were similar to those of the PCM.

Palm diesel : an option for greenhouse gas mitigation in the energy sector

The fast diminishing energy reserves coupled with increasing energy consumption as a nation develops and greater environmental awareness have led to an intensified search for viable alternate sources of energy. Natural and renewable resources such as vegetable oils can be chemically transformed into clean-burning biodiesel. Biodiesel is a fuel substitute that is biodegradable and can contribute to alleviating environmental pollution. Research and developmental efforts have demonstrated that palm diesel (palm oil methyl esters) is a good source for energy production. Palm diesel produced using patented PORIM/PETRONAS production technology has been extensively tested as a diesel substitute in a wide range of diesel engines including stationary engines, passenger cars, buses and trucks. Palm diesel exhibits fuel properties comparable to those of petroleum diesel and can be used directly in unmodified diesel engines. The production and usage of palm diesel has great environmental impact with its closed carbon cycle. A fuel switch from fossil fuel to palm diesel will contribute greatly to the reduction of greenhouse gas (GHG) emissions that lead to global warming. Therefore, palm diesel production, because of its contribution to lower GHG emissions, can generate carbon credits under the Clean Development Mechanism (CDM) of the Kyoto Protocol 1997. The financial incentives, like the attractive carbon credit scheme, would bring about an additional positive impact on the economic viability of palm diesel production as a renewable fuel. Furthermore, exhaustive field trials have also shown that diesel engines running on palm diesel do not emit black smoke. There are also reductions in carbon particulates, carbon monoxide and sulphur dioxide. The effort and initiative to utilize palm oil as an alternative energy source are also in line with the Malaysian Government’s five-fuel diversification policy to include renewable energy as the fifth fuel.

Environmental factors affecting the population density of oryctes rhinoceros in a zero-burn oil palm replant

The environment (abiotic and biotic factors) influences the survival of an organism. This study revealed several significant relationships between the population of Oryctes rhinoceros and the environment and physical characteristics of its habitat in an oil palm replant. Firstly, lower populations of O. rhinoceros occurred in areas with high cover crops over the decomposing chipped trunks. Secondly, high moisture content in the trunks was essential for the survival and satisfactory development of O. rhinoceros . Thirdly, there was a negative relationship between the number of developing pupae against the hardness of the trunk chips. This indicates that most of the pupae developed in the softer, decomposing chips. The larval population hastened the release of the trunk nutrients to the soil, especially K and Mg. Higher soil pH indirectly reduced the larval population of O. rhinoceros , possibly by promoting the growth of the entomopathogenic fungus, Metarhizium , which infected the larvae. This was reflected by the low number of adult beetles which emerged from the plots with high pH. Finally, rainfall induced the breeding of O. rhinoceros as shown by the high positive correlation between rainfall and the number of early instar larvae. Knowledge of some of these factors would enable planters to manipulate the habitat and its microclimate in order to manage the pest more effectively.

Illegitimacy in oil palm breeding – a review

Shell thickness and molecular marker data indicate that illegitimacy and contamination are more widespread in oil palm breeding programmes than is usually acknowledged. Before the discovery of the mode of inheritance of shell thickness, no markers were available to detect illegitimacy. Once shell thickness could be used as a marker, it became clear that control of pollination needed improvement. However, in present day programmes anomalous segregation ratios and contamination with the wrong fruit forms still occur from time to time, and work with molecular markers shows that illegitimacy may occur even when fruit form segregation is correct. Where there is illegitimacy, family selection will be unreliable, and inadvertent inbreeding may take place. Now that molecular markers are widely available, it should be standard practice in oil palm breeding to test all crosses for legitimacy. The requirements for this are discussed.

Book review : Land and Agricultural Policy : A Mismatch

Basir Ismail, Tan Sri Dato’ Seri Haji (2005), Land and Agricultural Policy: A Mismatch , Kuala Lumpur: Malaysian Palm Oil Board, 530 pp. ISBN 967-961-109-4. RM 150/USD 100.

In coming issue – volume 17 Dec 2005

  • Preliminary Study on Microbial Degradation of Flexible Polyurethane Foams – PhysicoMechanical and Weight Changes During Fungal Deterioration Razmah Ghazali; Lai Choon Mei; Norin Zamiah Kassim Shaari; Mohtar Yusof and Salmiah Ahmad
  • Spectroscopic Identification of Geometrical Isomers of α- and β-Carotenes from Palm Oil Bonnie Tay Yen Ping and Gwendoline Eee Cheng Lian
  • A New System for Continuous Sterilization of Oil Palm Fresh Fruit Bunches K Sivasothy; Rohaya Mohd Halim and Yusof Basiron
  • Polyploidy Induction of Oil Palm Through Colchicine and Oryzalin Treatments Maria Madon; Clyde Mahani Mansor; Hafizah Hashim; Yuhaniza Mohd Yusof; Hamidah Mat and Saratha, S
  • The Influence of Climatic Conditions on Gas and Energy Exchanges Above a Young Oil Palm Stand in North Kedah, Malaysia Ian E Henson and Mohd Haniff Harun
  • Best Development Practices and Sustainable Development of the Oil Palm Industry Chan Kook Weng