Abdul P.M.,National University of Malaysia |
Md. Jahim J.,National University of Malaysia |
Harun S.,National University of Malaysia |
Markom M.,National University of Malaysia |
And 3 more authors.
International Journal of Hydrogen Energy | Year: 2013
Oil palm empty fruit bunch (OPEFB) was pretreated by local plantation industry to increase the accessibility towards its fermentable sugars. This pretreatment process led to the formation of a dark sugar-rich molasses byproduct. The total carbohydrate content of the molasses was 9.7 g/L with 4.3 g/L xylose (C5H10O5). This pentose-rich molasses was fed as substrate for biohydrogen production using locally isolated Clostridium butyricum KBH1. The effect of initial pH and substrate concentration on the yield and productivity of hydrogen production were investigated in this study. The best result for the fermentation performed in 70 mL working volume was obtained at the initial reaction condition of pH 9, 150 rpm, 37 C and 5.9 g/L total carbohydrate. The maximum hydrogen yield was 1.24 mol H 2/mol pentose and the highest productivity rate achieved was 0.91 mmol H2/L/h. The optimal pH at pH 9 was slightly unusual due to the presence of inhibitors, mainly furfural. The furfural content decreased proportionally as pH was increased. The optimal experiment condition was repeated and continued in fermentation volume of 200 mL. The maximum hydrogen yield found for this run was 1.21 mol H2/mol pentose while the maximum productivity was 1.1 mmol H2/L/h. The major soluble metabolites in the fermentation were n-butyric acid and acetic acid. © 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
PubMed | University Putra Malaysia, Sime Darby Research Sdn Bhd and University of Cardiff
Type: | Journal: Insect science | Year: 2015
Integrated Pest Management (IPM) is widely practiced in commercial oil palm agriculture. This management system is intended to minimize the number of attacks by pest insects such as bagworms on crops, as well as curb economic loss with less dependency on chemical pesticides. One practice in IPM is the use of biological control agents such as predatory insects. In this study, we assessed the response of predatory natural enemies to pest outbreak and water stress, and document the habitat associations of potential pest predators. The abundances of two predatory insect species, namely Sycanus dichotomus and Cosmolestes picticeps (Hemiptera: Reduviidae), were compared bagworm outbreak sites and non-outbreak sites within oil palm plantations. We also examined habitat characteristics that influence the abundances of both predatory species. We found that the abundance of C. picticeps was significantly higher in bagworm outbreak sites than in non-outbreak sites. There were no significant differences in the abundance of S. dichotomus among outbreak and non-outbreak sites. Both species responded negatively to water stress in oil palm plantations. Concerning the relationship between predatory insect abundance and in situ habitat quality characteristics, our models explained 46.36% of variation for C. picticeps and 23.17% of variation for S. dichotomus. Both species of predatory insects thrived from the planting of multiple beneficial plants in oil palm plantations. The results suggest that C. picticeps can be used as a biological agent to control bagworm populations in oil palm plantations, but S. dichotomus has no or little potential for such ecosystem service. This article is protected by copyright. All rights reserved.
Latip R.A.,Sime Darby Research Sdn Bhd |
Lee Y.-Y.,University Putra Malaysia |
Tang T.-K.,University Putra Malaysia |
Phuah E.-T.,University Putra Malaysia |
And 2 more authors.
Food Chemistry | Year: 2013
The stearin fraction of palm-based diacylglycerol (PDAGS) was produced from dry fractionation of palmbased diacylglycerol (PDAG). Bakery shortening blends were produced by mixing PDAGS with either palm mid fraction, PMF (PDAGS/PMF), palm olein, POL(PDAGS/POL) or sunflower oil, SFO (PDAGS/SFO) at PDAGS molar fraction of XPDAGS = 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%. The physicochemical results obtained indicated that C16:0 and C18:1 were the dominant fatty acids for PDAGS/PMF and PDAGS/POL, while C18:1 and C18:2 were dominant in the PDAGS/SFO mixtures. SMP and SFC of the PDAGS were reduced with the addition of PMF, POL and SFO. Binary mixtures of PDAGS/PMF had better structural compatibility and full miscibility with each other. PDAGS/PMF and PDAGS/SFO crystallised in β'+β polymorphs in the presence of 0.4-0.5% PDAGS while PDAGS/POL resulted in b polymorphs crystal. The results gave indication that PDAGS: PMF at 50%:50% and 60%:40% (w/w) were the most suitable fat blend to be used as bakery shortening. © 2013 Elsevier Ltd.
Zulkurnain M.,University Putra Malaysia |
Zulkurnain M.,Universiti Sains Malaysia |
Lai O.M.,University Putra Malaysia |
Latip R.A.,Sime Darby Research Sdn Bhd |
And 3 more authors.
Food Chemistry | Year: 2012
The formation of 3-monochloropropane-1,2-diol (3-MCPD) esters in refined palm oil during deodorisation is attributed to the intrinsic composition of crude palm oil. Utilising D-optimal design, the effects of the degumming and bleaching processes on the reduction in 3-MCPD ester formation in refined palm oil from poor-quality crude palm oil were studied relative to the palm oil minor components that are likely to be their precursors. Water degumming remarkably reduced 3-MCPD ester formation by up to 84%, from 9.79 mg/kg to 1.55 mg/kg. Bleaching with synthetic magnesium silicate caused a further 10% reduction, to 0.487 mg/kg. The reduction in 3-MCPD ester formation could be due to the removal of related precursors prior to the deodorisation step. The phosphorus content of bleached palm oil showed a significant correlation with 3-MCPD ester formation. © 2012 Elsevier Ltd. All rights reserved.
Daliman S.,University of Technology Malaysia |
Abu-Bakar S.A.R.,University of Technology Malaysia |
Md Nor Azam S.H.,Sime Darby Research Sdn Bhd
IOP Conference Series: Earth and Environmental Science | Year: 2016
This paper presents development of Haar-based rectangular windows for recognition of young oil palm tree based on WorldView-2 imagery data. Haar-based rectangular windows or also known as Haar-like rectangular features have been popular in face recognition as used in Viola-Jones object detection framework. Similar to face recognition, the oil palm tree recognition would also need a suitable Haar-based rectangular windows that best suit to the characteristics of oil palm tree. A set of seven Haar-based rectangular windows have been designed to better match specifically the young oil palm tree as the crown size is much smaller compared to the matured ones. Determination of features for oil palm tree is an essential task to ensure a high successful rate of correct oil palm tree detection. Furthermore, features that reflects the identification of oil palm tree indicate distinctiveness between an oil palm tree and other objects in the image such as buildings, roads and drainage. These features will be trained using support vector machine (SVM) to model the oil palm tree for classifying the testing set and subimages of WorldView-2 imagery data. The resulting classification of young oil palm tree with sensitivity of 98.58% and accuracy of 92.73% shows a promising result that it can be used for intention of developing automatic young oil palm tree counting.
Jamaluddin M.T.,University Technology of MARA |
Ismail K.,University Technology of MARA |
Mohd Ishak M.A.,University Technology of MARA |
Ab Ghani Z.,University Technology of MARA |
And 6 more authors.
Renewable Energy | Year: 2013
In this study, response surface methodology (RSM) based on central composite rotatable design (CCRD) was applied to determine the optimum condition for pyrolysis of palm kernel shell (PKS) using microwave-assisted pyrolysis system. Three operating variables, namely reaction time (min), sample mass (g) and nitrogen gas flow rate (mL/min) with a total of 20 individual experiments were conducted to optimize the combination effects of the variables. RSM based upon CCRD can be applied to correlate the experimental microwave-assisted pyrolysis results, with regression coefficients of 96.6, 95.0, 96.4 and 99.2 for the calorific value, fixed carbon content, volatile matters content and yield percentage, respectively. This proved that the RSM based on CCRD is efficiently applicable for the pyrolysis study using microwave-assisted pyrolysis system. The predicted optimum conditions for the pyrolysis process was at 31.5 min for reaction time, 30 g for sample mass and 100 mL/min for nitrogen gas flow rate, resulting in calorific value, fixed carbon content, volatile matters content and yield percentage of 29.9 MJ/kg, 59.8 wt%, 36.4 wt% and 40.0 wt%, respectively. Thus, maximum production of PKS char, with low volatile matters content and high calorific value and fixed carbon content via microwave-assisted pyrolysis system can be optimized using RSM. © 2013 Elsevier Ltd.
Bakar R.A.,University Putra Malaysia |
Darus S.Z.,University Putra Malaysia |
Kulaseharan S.,University Putra Malaysia |
Jamaluddin N.,Sime Darby Research Sdn Bhd
Nutrient Cycling in Agroecosystems | Year: 2011
The oil palm empty fruit bunches (EFB), a major waste product of the palm oil mills, were earlier incinerated at the mills and had contributed to air quality problems in Malaysia. This lead to the introduction of the Malaysian Environmental Air Quality Regulation in 1978 which prompted mills to look for alternative management methods in disposal of the EFB. A convenient method is applying the EFB to the oil palm field near the mill for nutrient cycling. A study was conducted to investigate the effects of 10 years of EFB yearly application in an oil palm plantation, as a source of nutrients, on the chemical properties of a well-drained, highly weathered acidic soil, classified as Typic Kandiudult. The experimental plots receiving 3 treatments, i.e. chemical fertilization, without EFB application (CHEM)), application of 150 kg EFB palm-1 year-1 (EFB150) and application of 300 kg EFB palm-1 year-1 (EFB300) with four replications, from 1983 to 1992. The EFB was applied in heaps in the middle of every 4 palms. The cumulative addition of EFB had increased the soil pH by two units with application of EFB300 and a one unit increase with EFB150 in the 0-60 cm soil layer, compared to CHEM. The application of EFB even at the lower rate decreased significantly exchangeable Al contents and the cation exchange capacity increased up to 60 cm soil depth. Overall increases in exchangeable bases were also observed in soils treated with EFB. The increase was more evident in EFB300 compared to EFB150. Organic C in the topsoil increased from 1.49 to 2.50% and 2.73% in EFB150 and EFB300, respectively. There was also an increase in total nitrogen with EFB application but only in the topsoil. An overall analysis of the yield response in the 10 year-period shows that EFB300 resulted in higher fresh fruit bunch (FFB) yield than EFB150 and CHEM while the yield of EFB150 was not significantly different from CHEM. This study showed that it is beneficial to dispose the EFB by applying them in the oil palm fields around the mills. © 2010 Springer Science+Business Media B.V.
Arifin N.,University Putra Malaysia |
Arifin N.,Universiti Sains Islam Malaysia |
Soo-Peng K.,University Putra Malaysia |
Long K.,Malaysian Agricultural Research and Development Institute MARDI |
And 3 more authors.
Food and Bioprocess Technology | Year: 2012
Optimization conditions of Lipozyme RM IM lipase esterification of capric and stearic acids with glycerol for the production of medium- and long-chain triacyglycerols (MLCT) fat suitable for food applications such as margarine and shortening were investigated. Response surface methodology (RSM) was applied to model and optimize the reaction conditions, namely, the reaction time (8-24 h), enzyme load (5-15 Wt.%), and fatty acids/glycerol ratio (3:1-4:1) and represented by Ti, En, and Sb, respectively. Best-fitting models were successfully established for both MLCT yield (R 2 = 0.9507) and residual FFA (R 2 = 0.9315) established by multiple regressions with backward elimination. Optimal reaction conditions were 13.6-14.0 h for reaction time, 7.9-8.0 Wt.% for enzyme load, and 3:1 for fatty acids/glycerol molar ratio. Chi-square test showed that there were no significant (P>0.05) differences between the observed and predicted values of both models. Refined MLCT fat blend had sufficient solid fat at room temperature and made it suitable to use as a hard stock in shortening and margarine production. © 2010 Springer Science + Business Media, LLC.
PubMed | University Putra Malaysia and Sime Darby Research Sdn Bhd
Type: Comparative Study | Journal: Journal of food science | Year: 2016
The oxidative and thermal stability of low diglycerides palm oil produced via silica treatment (sPO) and enzymatic treatment (ePO) compared with standard quality palm oil (SQ) and premium quality palm oil (PQ) was investigated. Both of the oils displayed better oxidative stability compared with SQ as well as significantly higher (P < 0.05) thermal resistance and oxidative strength than SQ and PQ due to lower amounts of partial glycerides. Although the initial induction periods (IPs) of sPO and ePO were significantly lower compared with SQ and PQ, both the oils showed slower drops in their IP values. The darkening effect after frying was significantly (P < 0.05) slower in sPO compared with SQ, PQ, and ePO. Besides, there is no difference p > 0.05 in the rate of FFA formation between sPO and PQ. The anisidine value and peroxide values were lowest in sPO, followed by ePO, PQ, and SQ.
PubMed | University Putra Malaysia and Sime Darby Research Sdn Bhd
Type: Journal Article | Journal: Journal of food science and technology | Year: 2015
Structured lipid such as medium-and long-chain triacylglycerol (MLCT) is claimed to be able to suppress body fat accumulation and be used to manage obesity. Response surface methodology (RSM) with four factors and three levels (+1,0,-1) faced centered composite design (FCCD) was employed for optimization of the enzymatic interesterification conditions of palm-based MLCT (P-MLCT) production. The effect of the four variables namely: substrate ratio palm kernel oil: palm oil, PKO:PO (40:60-100:0 w/w), temperature (50-70C), reaction time (0.5-7.5h) and enzyme load (5-15% w/w) on the P-MLCT yield (%) and by products (%) produced were investigated. The responses were determined via acylglycerol composition obtained from high performance liquid chromatography. Well-fitted models were successfully established for both responses: P-MLCT yield (R (2)=0.9979) and by-products (R (2)=0.9892). The P-MLCT yield was significantly (P<0.05) affected by substrate ratio, reaction time and reaction temperature but not enzyme load (P>0.05). Substrate ratio PKO: PO (100:0 w/w) gave the highest yield of P-MLCT (61%). Nonetheless, substrate ratio of PKO: PO (90:10w/w) was chosen to improve the fatty acid composition of the P-MLCT. The optimized conditions for substrate ratio PKO: PO (90:10 w/w) was 7.26h, 50C and 5% (w/w) Lipozyme TLIM lipase, which managed to give 60% yields of P-MLCT. Up scaled results in stirred tank batch reactor gave similar yields as lab scale. A 20% increase in P-MLCT yield was obtained via RSM. The effect of enzymatic interesterification on the physicochemical properties of PKO:PO (90:10 w/w) were also studied. Thermoprofile showed that the P-MLCT oil melted below body temperature of 37C.