Purpose With increasing attention on sustainable development, the environmental and social relevance of palm oil production are now important trade issues. The life cycle assessment (LCA) study of Malaysian oil palm products from mineral soils including palm biodiesel was aimed to provide baseline information on the environmental performance of the industry for drawing up policies pertaining to the sustainable production. The share of greenhouse gas (GHG) contribution by the various subsystems in the oil palm supply chain is considered here. Materials and methods The life cycle inventory data for the study were collected based on subsystems, i.e., gate-to-gate. The subsystems include activities in oil palm nurseries and plantations, palm oil mills, refineries, biodiesel plants and the use of biodiesel in diesel engine vehicles. Two scenarios were considered: extraction of crude palm oil (CPO) in a mill without and with a system for trapping biogas from palm oil mill effluent (POME). Inventory data were collected through questionnaires. On-site visits were carried out for data verification. Background data for resource exploitation and production of input materials were obtained through available databases and literature. Foreground data for all subsystems were site-specific data from nurseries, plantations, palm oil mills and refineries and biodiesel plants in Malaysia. Results and discussion Using a yield of 20.7 t oil palm fresh fruit bunches (FFB)/ha, the results showed that the production of 1 t of FFB produced 119 kg CO 2 eq. The production of 1 t of CPO in a mill without and with biogas capture emitted 971 and 506 kg CO 2 eq, respectively. For the production of 1 t of refined palm oil in a refinery which sourced the CPO from a mill without biogas capture and with biogas capture, the GHG emitted was 1,113 kg and 626 kg CO 2 eq, respectively. For palm biodiesel, 33.19 and 21.20 g CO 2 eq were emitted per MJ of biodiesel produced from palm oil sourced from a mill without and with biogas capture, respectively. Conclusions GHG contribution by the nursery subsystem was found to be minimal. In the plantation subsystem, the major sources of GHG were from nitrogen fertilizers, transport and traction energy. For the mill, biogas from POME was the major contributor if biogas was not trapped. Excluding contribution from upstream activities, boiler fuel and transport were the major sources of GHG in the refinery subsystem. In the biodiesel subsystem, activities for production of refined palm oil and methanol use were the most significant contributors.

The effects of frying duration, frying temperature and concentration of sodium chloride on the formation of 3-monochloropropane-1,2-diol (3-MCPD) esters and glycidyl esters (GEs) of refined, bleached and deodorized (RBD) palm olein during deep-fat frying (at 160°C and 180°C) of potato chips (0%, 1%, 3% and 5% NaCl) for 100min/d for five consecutive days in eight systems were compared in this study. All oil samples collected after each frying cycle were analyzed for 3-MCPD esters, GEs, free fatty acid (FFA) contents, specific extinction at 232 and 268 nm (K and K), p-anisidine value (pAV), and fatty acid composition. The 3-MCPD ester trend was decreasing when the frying duration increased, whereas the trend was increasing when frying temperature and concentration of NaCl increased. The GEs trend was increasing when the frying temperature, frying duration and concentration of NaCl increased. All of the oil qualities were within the safety limit.

Hexaconazole is a potential fungicide to be used in the oil palm plantation for controlling the basal stem root (BSR) disease caused by Ganoderma boninense. Therefore, the dissipation rate of hexaconazole in an oil palm agroecosystem under field conditions was studied. Two experimental plots were treated with hexaconazole at the recommended dosage of 4.5 g a.i. palm(-1) (active ingredient) and at double the recommended dosage (9.0 g a.i. palm(-1)), whilst one plot was untreated as control. The residue of hexaconazole was detected in soil samples in the range of 2.74 to 0.78 and 7.13 to 1.66 mg kg(-1) at the recommended and double recommended dosage plots, respectively. An initial relatively rapid dissipation rate of hexaconazole residues occurred but reduced with time. The dissipation of hexaconazole in soil was described using first-order kinetics with the value of coefficient regression (r (2) > 0.8). The results indicated that hexaconazole has moderate persistence in the soil and the half-life was found to be 69.3 and 86.6 days in the recommended and double recommended dosage plot, respectively. The results obtained highlight that downward movement of hexaconazole was led by preferential flow as shown in image analysis. It can be concluded that varying soil conditions, environmental factors, and pesticide chemical properties of hexaconazole has a significant impact on dissipation of hexaconazole in soil under humid conditions.

This paper examines the interactions of degumming and bleaching processes as well as their influences on the formation of 3-monochloropropane-1,2-diol esters (3-MCPDE) and glycidyl esters in refined, bleached and deodorized palm oil by using D-optimal design. Water degumming effectively reduced the 3-MCPDE content up to 50%. Acid activated bleaching earth had a greater effect on 3-MCPDE reduction compared to natural bleaching earth and acid activated bleaching earth with neutral pH, indicating that performance and adsorption capacities of bleaching earth are the predominant factors in the removal of esters, rather than its acidity profile. The combination of high dosage phosphoric acid during degumming with the use of acid activated bleaching earth eliminated almost all glycidyl esters during refining. Besides, the effects of crude palm oil quality was assessed and it was found that the quality of crude palm oil determines the level of formation of 3-MCPDE and glycidyl esters in palm oil during the high temperature deodorization step of physical refining process. Poor quality crude palm oil has strong impact towards 3-MCPDE and glycidyl esters formation due to the intrinsic components present within. The findings are useful to palm oil refining industry in choosing raw materials as an input during the refining process.

had no significant effect on the GE generation. The FFA contents, K 232 and K 268 and pA showed that all the frying oils were within the safety limit.