Category Archives: 2021 Vol 33 Sept

DRYING OF OIL PALM LUMBER BY COMBINING AIR FORCE DRYING AND MODIFIED SUPERFAST DRYING METHODS

In this study, super-fast drying (SFD) method was modified by adding forced-air drying (AFD) method in the beginning stage. The modified drying method is called modified super-fast drying (MSFD). This method eliminates the holing process in SFD and makes it more favourable by wood-based manufacturers. Inner and outer portion of oil palm lumber (OPL) were segregated and dried using both SFD and MSFD methods. The drying rate and drying defects of the OPL dried with AFD method were compared with conventional air drying (AD) method. The OPL dried with MSFD were compared with SFD in terms of drying defects, rate, physical and mechanical properties. The results revealed that AFD method exhibited significantly effective drying rate compared to AD by shorten the time needed to achieve desired moisture content (MC). On the other hand, MSFD were found to be able to reduce the outer OPL to 10% within 3 hr. The SFD method reported the same rate of drying performance. However, MSFD did not involve the unfavourable holing process as in SFD method. In addition, OPL dried using MSFD exhibited better mechanical and physical properties than SFD. The findings suggested the MSFD method is an enhanced method compared to SFD method.

MOLECULAR CLONING OF Elaeis guineensis PHYTOENE SYNTHASE (Egpsy) AND ITS EXPRESSION IN MESOCARP TISSUES

Phytoene synthase (psy) gene is responsible for the synthesis of carotenoids in plants. In this study complimentary DNA (cDNA) and genomic sequences of psy were isolated by rapid amplification of cDNA ends and polymerase chain reaction (PCR) using ribonucleic acid (RNA) and deoxyribonucleic acid (DNA) isolated from the mesocarp tissues of oil palm (Elaeis guineensis). The size of the full-length cDNA was 2233 bp. The open reading frame (ORF) was 1299 bp and encoded 433 deduced amino acid (AA) residues. The transcript profile revealed that psy was expressed at a maximum level at 12 weeks after anthesis (WAA). The lowest expression of psy was at 13 WAA, which was speculated as the transition of the leaf-like carotenoid to the formation of storage carotenoids. The AA sequence deduced from the cDNA was 70%- 78% identical to PSY from other higher plants. The genomic sequence analysis revealed that the psy gene contains six exons and five introns. Southern blot analysis indicated that oil palm has only one copy of the psy gene in its genome.

QUALITY IMPROVEMENT OF PALM KERNEL CAKE AS BROILER FEED USING PRE-CLEANING SYSTEM

The use of palm kernel cake (PKC) in broiler feed is limited due to high fibrous material contributed mainly by dirt and shell, exceeding 6%. The fibrous component consists of mainly insoluble mannosebased polysaccharides which is not suitable for monogastric animals such as poultry and swine. This study highlights the development of a pre-cleaning system consisting of three-stage winnowing columns to reduce the shell content in kernel by less than 4% prior to oil extraction. In this study, the palm kernels received from 21 palm oil mills were subjected to dirt and shell content analysis. To produce palm kernel with low shell content, the pre-cleaning system was optimised. Further analysis on nutrient values was also carried out for premium grade PKC produced, also known as Purafex, from the clean kernels of low shell content (<4%) after pre-cleaning. A feeding trial was carried out to study the effect of different Purafex inclusion in the dietary treatment on the broilers performance. Results showed that the dirt and shell contents in the kernels varied from 3.48%–5.18%. The nutrient values and quality of Purafex conformed to that of standard specifications by Malayan Edible Oil Manufacturers’ Association (MEOMA). Reduction of shell and fibre in kernel reduces the crude fibre in Purafex from ≥15% to ≤12%, which is far below the fibre in commercial PKC, thus making it digestible for monogastric animals. Better performance in terms of body weight gain (BWG) and feed intake (FI) were exhibited when 15%–30% Purafex were included in feeding trials compared to those of 45% inclusion.

RHEOLOGICAL PROPERTIES OF PALM-BASED CARBOXYMETHYL CELLULOSE SOLUTIONS

Palm empty fruit bunches have been value added into carboxymethyl cellulose (CMC). However, its potential as rheological modifiers in cosmetic and personal care has yet to be explored. Therefore, the aim of this study was to investigate the rheological performance of the CMC solutions (1%, 2%, 3% and 4%) against two commercially available CMC (cotton-based and wood-based CMC). Our study revealed that all the CMC solutions studied gave flow behaviour index of less than 1, which indicated the pseudoplastic or shearthinning properties. Among the three CMC studied, 2% and 3% CMC from palm empty fruit bunches (PEFB-CMC) and cotton-based CMC exhibited viscoelastic solid properties where the storage modulus (G’) was larger than loss modulus (G”) on amplitude sweep test. On the other hand, all the wood-based CMC did not exhibit any viscoelastic solid properties. In addition, the 2% palm-based CMC exhibited higher gel strength as compared to 2% cotton-based CMC solution, while the wood-based CMC exhibited fluidstructure through frequency sweep test. The palm-based CMC exhibited potential application as rheological modifier in consumer products particularly for the development of cosmetic and personal care products.

PRODUCTION OF FURFURAL FROM OIL PALM FIBRES

Furfural is a chemical compound produced by biomass rich in pentoses content in the hemicellulose as raw material, in a reaction catalysed in presence of strong acids. This study determines the process parameters for converting xylan, extracted from oil palm empty fruit bunches (OPEFB), into furfural using a two-step process, namely acid hydrolysis, followed by dehydration. Xylan was first extracted from OPEFB using direct alkaline extraction method. The resulting xylan was then treated with a known concentration of sulphuric acid (H2SO4) (ranging from 11% v/v~15% v/v) with reaction time (ranging from 30-150 min), with or without presence of sodium chloride (NaCl) as co-catalyst to produce xylose. After dehydration process, xylose was converted into furfural with parameters as in dehydration process. Furfural was characterised using Fourier transform infra-red (FTIR) and Proton nuclear magnetic resonance (1H-NMR). FTIR spectrum exhibited a very strong absorption at 1706 cm–1, indicating the presence of the conjugated carbonyl (C=O) group. The highest yield of furfural produced was 9.01% after treatment with 15% H2SO4 using NaCl as catalyst for 90 min. However, pentosans only contribute a portion of the total composition of lignocellulose, compared to cellulose which is the largest fraction of lignocellulosic biomass. Therefore, the furfural should be extracted using an integrated value economy method.

OIL PALM MALE MEIOSIS PROFILING: FROM FIELD OBSERVATION TO CYTOGENETICS ANALYSIS

Male meiosis is a principal process in microsporogenesis, important for male fertility and gamete viability in higher plants. This division ensures genome stability of sexually reproducing organisms and creates genome variation enabling diversity in a species. We present a structured profiling of male meiosis in the interspecific oil palm hybrid, Elaeis oleifera × Elaeis guineensis (OxG), for an in-depth understanding of the process. In the pollen mother cells (PMC), interaction between the parental genomes was observed in early prophase I, via genomic in situ hybridisation (GISH). At this meiosis I stage, the chromosome pairing revealed 16 complete bivalents, confirming the homologous pairing of each E. guineensis and E. oleifera chromosomes. Interestingly, we found that the E. guineensis and E. oleifera pollens had distinct morphologies, which represents another feature that differentiates the two species. This could also be used as a basis diagnostic tool to evaluate sterility in oil palm interspecific hybrids.

PREDICTION OF ACID, PEROXIDE AND TBA VALUES OF HEAT-TREATED PALM OIL USING A PARTIAL LEAST SQUARES–ORDINARY LEAST SQUARES MODEL BASED ON FOURIERTRANSFORM INFRARED SPECTROSCOPY

Palm oil is widely used for frying food and is often used for repeated frying up to 40 hr or even longer. Frying causes a gradual quality decrease during heating due to fat oxidation or hydrolysis. The quality of fats and oils is commonly monitored by acid, peroxide and thiobarbituric acid values (AV, PV and TBAV, respectively). This study aimed to use a partial least squares–ordinary least squares (PLS-OLS) model obtained from fourier-transform infrared (FT-IR) spectroscopy to predict AV, PV and TBAV values of heat-treated palm oil. Commercial palm oil was heated at 180oC for 72 hr. The multivariate mathematical models to predict AV, PV and TBAV were generated from the percentages of absorbance intensity of significant wavenumbers based on FT-IR readings (721.4 cm–1, 871.8 cm–1, 968.3 cm–1, 1033.9 cm–1, 1095.6 cm-1, 1377.2 cm–1, 1462 cm–1, 1751.4 cm–1, 2731.2 cm–1, 2839.2 cm–1 and 3005.1 cm–1). The PLS-OLS mathematical model satisfactorily predicted both AV and PV for palm oil samples heated up to 72 hr (R2 = 0.962 and 0.857, respectively), whereas for TBAV, the time was 58 hr (R2 = 0.845). This approach provides an alternative to monitoring palm oil quality during frying instead of the conventional methods in which the analytical procedures are time-consuming.

NEURAL NETWORKS METHOD IN PREDICTING OIL PALM FFB YIELDS FOR THE PENINSULAR STATES OF MALAYSIA

Reliable and accurate predictions in oil palm production can provide the basis for management decisions of budgeting, storage, distribution, and marketing. Artificial Neural Network (ANN) and Non-linear Autoregressive Exogenous Neural Network (NARX) models were developed based on 19 440 data set of 15 inputs variables, namely, percentage of mature area and percentage of immature area, rainfall, rainy days, humidity, radiation, temperature, surface wind speed, evaporation and cloud cover, ozone (O3), carbon monoxide (CO), nitrogen dioxide (NO2), sulphur dioxide (SO2), and particulate matter of less than 10 microns in size (PM10) for predicting oil palm fresh fruit bunch (FFB). The results were validated with an independent validation dataset. Results showed that NARX models performed more accurately with multiple coefficients of determination (R2) reached 97% and mean square errors (MSE) between 0.0104%-0.0665%, besides being an easy-to-use tool. Generally, NARX models proved to give more accurate predictions than the predictions of common ANN and Multi Linear Regression (MLR) models. Finally, 15-10-4-1 is chosen as the architecture of NARX for the states of Kedah, Kelantan, Perak, Pahang, Selangor, and Terengganu. The 15-7-4-1 is the best architecture of NARX for the state of Melaka and Pulau Pinang, while 15-13-4-1 architecture is for the state of Johor. This study showed that all of these architectures gave high accuracy with acceptable MSE values.

PRINCIPAL COMPONENT ANALYSIS (PCA) EVALUATION OF LIQUID CHROMATOGRAPHYMASS SPECTROMETRY (LC-MS) DATASETS OF Ganoderma boninense INTRACELLULAR METABOLITES

Liquid chromatography-mass spectrometry (LC-MS) has become a powerful analytical technique for studying broad coverage of chemical datasets describing complex biological systems and events. In order to interpret the underlying information in such datasets, multivariate analysis method such as principal component analysis (PCA) is crucial for multiple sample comparisons and multivariate data reduction. PCA has been used for evaluation of large-scale datasets derived from LC-MS analysis of fungal metabolites for many applications. Therefore, in this study, we describe on PCA as a descriptive tool to cope with large LC-MS datasets of intracellular metabolites of oil palm basal stem rot (BSR) fungal pathogen, Ganoderma boninense from in vitro liquid culture system. The results revealed a classification and grouping of G. boninense intracellular metabolites according to time trend, where the primary metabolites, i.e. glucose, gluconic acid, mannitol and malic acid were found differentially expressed in G. boninense. The presented findings suggest that the PCA model provides a general approach for handling, analysis and interpretation of large LC-MS datasets to reveal time-dependent changes of intracellular metabolites that may indicate G. boninense developmental process in vitro.

DEVELOPMENT OF PALM-BASED VANASPATI (VEGETABLE GHEE): EFFECTS OF CRYSTALLISATION PROCEDURES ON THE PRODUCT TEXTURE

Trans free vanaspati (vegetable ghee) formulated using a blend of refined, bleached and deodourised (RBD) palm stearin with iodine value of 30 (POs IV30) and palm olein with iodine value of 58 (POo IV58) in 40:60 w/w ratio was produced. The effect of mixing procedure on the crystallisation of the blend was investigated. VC-1 treatment which involved mixing of POs IV30 at 24ºC into POo IV58 at 65ºC and mixing the blend to a complete melt at room temperature followed by tempering at 25ºC produced a granulated vanaspati with spherical or granular shape crystals. VC-2 treatment which involved the mixing of POs IV30 at 55ºC into POo IV58 at 24ºC and mixing the blend to a complete melt at room temperature followed by tempering at 25ºC produced small crystals which is suitable for the production of smooth textured vanaspati. Vanaspati produced using VC-3 treatment which involved the mixing of POs IV30 at 24ºC into POo IV58 at 65ºC but was not mixed to a complete melt, followed by tempering at 25ºC produced small crystals and loosely packed structure which led to the formation of a slightly grainy textured vanaspati. Thus, a consistent and homogenous grainy textured vanaspati could be produced under controlled conditions using treatment VC-1 and this will be able to resolve the problem of inconsistency of texture in 100% palm-based grainy vanaspati. Grainy vanaspati is preferred by consumers in India and Pakistan where the demand of vanaspati is very high.

IS PALM MID FRACTION A HEALTHIER CHOICE AS A COCOA BUTTER EQUIVALENT?

Palm mid fraction (PMF) is a fraction of palm oil rich in 1, 3-dipalmitoyl-2- oleoylglycerol (POP) triacylglycerol (TAG) that is obtained through re-fractionation of either palm olein or palm stearin. POP-, 1(3)-1, 3 distearoyl-2-oleoylglycerol (SOS)- and triolein (OOO)- type of fats have different melting characteristics that may affect postprandial lipid and glucose metabolism. We aimed to study the effects of palmitic, stearic or oleic acid situated at the sn-1 and sn-3 positions of edible fats on postprandial lipemia, glucose and insulin responses. A randomised, double-blind crossover (3 x 3 arms) orthogonal Latin-square design was used. A total of 36 healthy adults received three different test muffins, each containing 53 g of test fat from palm mid fraction (PMF as POP-rich fat), shea stearin (SS as SOS-rich fat) or high-oleic sunflower oil (HOSF as OOO-rich fat) plus a low-fat milkshake in random order separated by two weeks. No significant differences (P>0.05) were observed between the three test meals for postprandial responses in plasma total cholesterol, Lp(a), glucose and insulin levels. However, plasma TAG levels were found significantly higher (P<0.05) in PMF- and HOSF- subjects compared with SS- subjects after 90 min. Plasma C-peptide levels were found lower (P<0.05) in the SS-subjects compared to the PMF- and HOSF- subjects. The results suggested that dietary fats containing palmitic (PMF) and oleic acid (HOSF) at the sn-1, 3 positions of the TAG backbone exert similar postprandial lipid and glucose responses compared with that of a stearic acid-rich sn-1,3 dietary fat (SS). In the food industry, there is demand for edible fats with different forms of TAG which can serve as a cocoa butter equivalent (CBE) i.e. as an important alternative for chocolates and other confectionary products.

IDENTIFICATION AND DETERMINATION OF THE SPECTRAL REFLECTANCE PROPERTIES OF LIVE AND DEAD BAGWORMS, Metisa plana WALKER (Lepidoptera: Psychidae) USING VIS/ NIR SPECTROSCOPY

The bagworm is one of main and serious leaf eating insect pest threats of the oil palm plantations in Malaysia. The economic impact from a moderate bagworm attack of 10%-50% leaf damage may cause 43% yield loss. The population of bagworms without control often increases to above its threshold limits, thereby causing a serious outbreak. Monitoring and detection of the oil palm bagworm population is required to ensure proper planning of any control actions in the infested areas. Hence, a study on the determination of the spectral signature of the bagworm species of Metisa plana Walker was initiated by using Visible/Near Infrared (Vis/NIR) spectroscopy. Live and dead bagworm spectral properties were determined under the Vis/ NIR wavelength regions, 350-1050 nm to provide specific infrared detector and band filter for development of an automated counter of the bagworms. The results showed that the live and dead bagworms had specific reflectance spectra at a specific wavelength in the NIR range spectral, ranging from 1032-1051 nm and these were statistically confirmed using the Student’s t-Test with two tailed distributions. A principal component analysis (PCA) resulted that the first two principal components, F1 and F2 have eigenvalues greater than 1, at 2.11 and 1.24, respectively. Using a Boxplot Quantiles, the results showed that the lowest and highest means of the reflectance spectra observed for the live bagworms were approximately 3.43% and 26.42%, respectively. Meanwhile, for the dead bagworms, the lowest and highest reflectance spectra observed were 4.02% and 34.29%, respectively. These spectral data were important to determine the suitable infrared (IR) instrumentation for detection of every stage of the live and dead bagworms. This information will be useful, important and crucial for development of an automated detector of insect pest in the future.

PRELIMINARY STUDY ON EFFICIENCY OF DIFFERENT TIME AND LIGHT SOURCE IN LIGHT TRAPS FOR CAPTURING POPULATION OF ADULT OIL PALM BUNCH MOTH, Tirathaba mundella (Lepidoptera: Pyralidae)

The oil palm bunch moth, Tirathaba mundella (Lepidoptera: Pyralidae) is a pest of oil palm especially those planted on peat soil. The pest has a short life cycle, approximately 30 days (eggs four days, larvae 16 days and pupae 10 days) and therefore, its population build up rapidly and causing severe damage to the oil palm when proper control is not in place. A research was conducted to determine the efficiency of different design of the light traps in capturing the adult bunch moths and also, aimed to observe the moths’ behaviour in terms of the night flight pattern in the areas with high level of infestation. The study was carried out in two oil palm estates in Sarawak; Location A, Daro and Location B, Sri Aman, from 17-19 July 2018 and 23-25 January 2019, respectively. Six light traps (Location A) and three light traps (Location B) were tested. Night flight activities were recorded for three different intervals; Interval 1 (1925-2125), Interval 2 (2130-2330) and Interval 3 (2335-0135). The result showed that, light Trap 6 was found to be the most attractive in Location A, capturing significantly higher number of moths (mean=38.6667, p<0.05). Whereas, in Location B, Trap 2 recorded the highest number of total individual moths captured but, not significantly different from other designs (mean=18, p>0.05). In terms of the moths’ behaviour, the third interval showed significantly greater number of individual female moths captured compared to the other two intervals in Location A (mean=16, p<0.05). However, in Location B, it was found that the amount of captured female moths in the earlier time intervals (Intervals 1 and 2) was significantly greater (mean=8 and 9.6667 individuals, p<0.05) than final time interval (two individuals), which was opposite to the observations made in Location A. The cause of such behaviour is still unknown and thorough study is needed. Thus, in future study, the data as such additional climatic parameters need to be incorporated (e.g. ambient temperature, humidity, moon phase and wind speed) for further understanding of the behaviours and preferences of the pest. Furthermore, the study also indicates potential application of light trapping as one of the alternatives to the oil palm pest management.

QUALITY OF COMMERCIAL PALM-BASED COOKING OIL PACKED IN PLASTIC POUCH AND POLYETHYLENE TEREPHTHALATE (PET) BOTTLE

The study compared the quality of palm cooking oil sold in two types of packaging in Malaysia; plastic pouch (16 samples) and polyethylene terephthalate (PET) bottle (9 samples). The study was conducted because consumer perceived that the quality of palm cooking oil in plastic pouch is lower than in the PET bottle due to its lower price. Cooking oil in plastic pouch is subsidised by the Government of Malaysia and as such, it is sold at a cheaper price compared to bottled cooking oil. Therefore, comparison of the initial quality in terms of free fatty acid (FFA), fatty acid composition (FAC), triacylglycerol composition (TAG), total vitamin E, iodine value (IV), cloud point, smoke point, colour, polar compound, polymer compound and oxidative stability index (OSI) of the commercial palm cooking oils were conducted between the cooking oil in plastic pouch and PET bottle. The quality parameters of average FFA, FAC (oleic, linoleic, palmitic and stearic acids), IV and colour (red and yellow) of cooking oil in both packagings met the specifications or guidelines by either Malaysian Standard (MS) 682:2004, MS 816:2007 or Palm Oil Refiners’ Association (PORAM) specifications/guidelines. However, quality parameters of TAG, total vitamin E, cloud point, smoke point, polar compound, polymer compound and OSI are not specified in any of the standards above. After conducting a 2-sample t-test to detect differences of cooking oil in both packagings, quality parameters of average FFA, FAC (oleic acid), total vitamin E, colour (red, yellow, neutral and blue), polar compound and polymer compound were comparable between cooking oil in plastic pouch and PET bottle. However, the FAC (palmitic acid, stearic acid and linoleic acid), TAG [UUU (unsaturated-unsaturated-unsaturated) and SUU (saturated-unsaturated-unsaturated)], IV and cloud point quality of cooking oil in PET bottle were better than in plastic pouch in which FAC (stearic acid and linoleic acid), TAG [UUU (unsaturated-unsaturated-unsaturated) and SUU (saturated-unsaturated-unsaturated)] and IV in PET bottle showed higher value while and FAC (palmitic acid) and cloud point showed lower value than plastic pouch in this study. Notwithstanding this, the smoke point and OSI quality of commercial palm cooking oil in plastic pouch was better than in PET bottle, having higher values than plastic pouch. TAG [SUS (saturated-unsaturated-saturated)] of commercial cooking oil in plastic pouch was also higher than in PET bottle but did not necessarily provide indication of good quality cooking oil.

POTENTIAL OF FUNCTIONALISED CELLULOSE FROM OIL PALM BIOMASS AS NITROGEN AND PHOSPHORUS BASED NUTRIENT ADSORBENT – A REVIEW

By the year 2020, oil palm biomass in Malaysia is projected to reach between 85-110 million tonnes per year. Instead of disposing off such a massive amount of biomass as waste, the oil palm biomass could be converted into value-added products. Since lignocellulosic materials could be a suitable adsorbent for nitrogen and phosphorus-based nutrients from aquaculture effluent based on studies conducted by other countries, it would be an excellent opportunity to monetise oil palm biomass for a similar purpose as well. There are many well-established extraction methods introduced by researchers. However, only a handful of the extraction method involved the use of green chemicals. This paper provides a review of the extraction and modification for oil palm biomass towards becoming a potential adsorbent for nitrogen and phosphorus-based nutrients.