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Background: A green approach to synthesize nanomaterials using biotemplates has been subjected to intense research due to several advantages. Palm olein as a biotemplate offers the benefits of eco-friendliness, low-cost and scale-up for large scale production. Therefore, the effect of palm olein on morphology and surface properties of ZnO nanostructures were investigated. Results: The results indicate that palm olein as a biotemplate can be used to modify the shape and size of ZnO particles synthesized by hydrothermal method. Different morphology including flake-, flower- and three dimensional star-like structures were obtained. FTIR study indicated the reaction between carboxyl group of palm olein and zinc species had taken place. Specific surface area enhanced while no considerable change were observed in optical properties. Conclusion: Phase-pure ZnO particles were successfully synthesized using palm olein as soft biotemplating agent by hydrothermal method. The physico-chemical properties of the resulting ZnO particles can be tuned using the ratio of palm olein to Zn cation. [ABSTRACT FROM AUTHOR]

The influence of fat quantity and composition on the characteristics of a chemically leavened baked product was investigated, applying a central composite design combined with response surface methodology. Fats were blends of palm oil and palm olein with different slip melting points (from 36.3 to 11.3 °C, in dependence of increasing olein content). Fat content (from 5.3% to 30.7% on batter) and percentage of olein in the fat blend (from 42.7% to 92.2%) were varied. The increase of fat quantity enhanced cake softness, while lowering the volume; higher olein contents also decreased cake firmness. An optimised formulation containing 19.7% fat with 92% olein in the fat blend and showing good structural properties, comparable to those of a 18% butter reference cake, was identified. The optimised and the butter cake showed specific volume of 2.25 and 2.23 cm3 g−1, respectively, and load at 25% strain of 7.68 and 5.63 N. These results demonstrated the possibility to replace butter with a liquid vegetable fat blend, thus increasing unsaturated fat content and reducing total cholesterol in the product. [ABSTRACT FROM AUTHOR]

Palm olein is currently considered to be one of the best options for deep-frying, but as with any other edible oil, during frying, deteriorative reactions produce off-flavor compounds that reduce the oil sensory quality. This study assessed the odor significance of the volatiles formed during 136 h of deep-frying a chicken product in palm olein, aiming to identify potential markers of the oil sensory quality during frying. The volatiles were isolated by solid phase microextraction, and identified by GC-MS. Trained judges assessed the odor intensity and quality of the volatiles formed during frying, evaluating the GC effluents through a GC-olfactometry technique called OSME. Two hundred and eight volatiles were detected by GC/MS in the palm olein after 136 h frying. Of these, heptanal, t-2-heptenal, decanal and t-2-undecenal were identified as potential markers of the sensory quality of palm olein during frying. Hexanal, pentanal and pentane, usually associated with lipid oxidation, showed no odor impact in the GC effluents, and were thus proven not to be good markers of the sensory quality of palm olein when used for a long frying period. [ABSTRACT FROM AUTHOR]

Background Effects of palm olein (POL) on calcium and fat metabolic balance and gastrointestinal (GI) tolerance have been clinically evaluated but its use in combination with palm kernel oil (PKO), and canola oil has not been similarly assessed in infants. Methods Calcium and fat balance and GI tolerance were evaluated in 33 healthy term infants (age = 68-159d) in a randomized, double-blinded, 14d crossover trial at a day care center in Salvador, Brazil; followed by a 4d hospital ward metabolic balance study in 17 of the male subjects. The study compared two commercially available milk-based powdered formulas in Brazil; one containing POL (44% of total fat), PKO (21.7%) and canola oil (18.5%) as predominant fats (PALM), and the other containing none (NoPALM). Occasional human milk (HM) supplementation was allowed at home. Results Formula and HM intakes, and growth were not different (p > 0.05). Calcium absorption (%) for infants fed NoPALM (58.8 ± 16.7%; means ± SD) was higher (p = 0.023) than those fed PALM (42.1 ± 19.2%), but was not significant (p = 0.104) when calcium intake was used as a covariate. Calcium intake was higher (p < 0.001) in NoPALM versus PALM fed infants. However, calcium retention (%) was higher in infants fed NoPALM compared to PALM with (p = 0.024) or without (p = 0.015) calcium intake as a covariate. Fat absorption (%) for NoPALM was greater than PALM fed infants (NoPALM = 96.9 ± 1.2 > PALM = 95.1 ± 1.5; p = 0.020 in Study Period I). Mean rank stool consistency was softer in infants fed NoPALM versus PALM (p < 0.001; metabolic period). Adverse events, spit-up/vomit, fussiness and gassiness were not different (p > 0.05). Formula acceptability was high and comparable for both formula feedings, regardless of HM supplementation. Conclusions Term infants fed PALM based formula (containing palm olein, palm kernel and canola oils) demonstrated lower calcium retention and fat absorption, and less softer stool consistency versus infants fed NoPALM based formula. Study suggested formula fat differences may affect GI function in infants. [ABSTRACT FROM AUTHOR]

A study to measure frying quality and stability of rice bran oil (RBO) compared to palm olein (PO) was conducted. The oils were used to fry French fries continuously for six hours a day up to five days at a temperature of 185 ± 5°C. Oil samples were collected and analyzed for free fatty acid (FFA), peroxide value (PV), smoke point, p-anisidine value (p-AV), iodine value (IV) and colour. At the end of the frying period for both oil samples, FFA, PV, colour and p-AV were increased whereas the IV and smoke point decreased. The rate of FFA formation of RBO was slightly lower which increased from 0.142% to 0.66% compared to PO which was from 0.079% to 0.93%. The PV of RBO showed consistent increased from 3.9 meq/kg to 13.4 meq/kg whereas PO with initial value at 3.4 meq/kg increased to 34.6 meq/kg on the fifth day. Smoke point of RBO and PO progressively dropped from 235°C to 188°C and 220°C to 178°C, respectively. The level of p-AV for RBO increased from 12.19 to 32.65 from the initial to the end of frying day whereas PO had higher rate of changes in p-AV which was from 10.45 to 60.75. The IV decreased over frying time where IV of RBO decreased from 94.5 to 66.5 while IV of PO decreased from 50.9 to 44.6. The colour of RBO showed increased in redness and yellowness but PO was darker at the end of the frying trial. In general, RBO showed better stability than the PO in deep frying of French fries. [ABSTRACT FROM AUTHOR]

Abstract: Vegetable oil is one of the bio-oils that have been promoted to replace petroleum-based products due to its eco- friendly characteristics. Palm oil has high productivity rate, and so it could fulfil the demand for a bio-lubricant. In this paper, the influence of the normal load on friction and wear performance were investigated for a RBD palm olein and compared with paraffinic mineral oil using four-ball tribotester. The normal load was varied from 30 kg to 60 kg. All experimental works were conforming to ASTM D 4172. The results exhibited that the RBD palm olein has lower coefficient of friction compared to paraffinic mineral oil. However, the wear scar of ball bearings lubricated with RBD palm olein showed larger diameter compared to paraffinic mineral oil. As a conclusion, RBD palm olein has better performance compared to paraffinic mineral oil in terms of capability to reduce friction. [Copyright &y& Elsevier]

The changes occurring in the levels of nutritionally relevant oil components were assessed during repeated frying of potato chips in a blend of palm olein and canola oil (1:1 w/w). The blend suffered minimal reductions in omega-3 and omega-6 polyunsaturated fatty acids. There was no significant difference between the fatty acid composition of the oil extracted from the product and that of the frying medium, in all three cases. The blend also contained a significant amount of tocols which add a nutritional value to the oil. The concentration of the tocols was satisfactorily retained over the period of oil usage, in contrast to the significant loses observed in the case of the individual oils. The blend also performed well when assessed by changes in total polar compounds, free fatty acids, p-anisidine value. When fried in used oil, the product oil content increased progressively with oil usage time. This study shows that blended frying oils can combine good stability and nutritional quality. [ABSTRACT FROM AUTHOR]

Performance of soybean oil and palm olein during the deep-fat frying of 45 batches of frozen prefried french fries was studied. The peroxide index increased faster for the soybean oil, with a final value of 12 meq/kg. Free fatty acids increased with the number of fried batches and were higher in the palm olein. Total color change was more noticeable in soybean oil in comparison to the palm olein. Viscosity, total polar compounds, and p-anisidine values increased and were higher in soybean oil. A reduction of unsaturated fatty acids was observed from the chromatography analysis. Elaidic and linoelaidic acids, which are trans-fatty acids, had higher concentrations in degraded soybean oil. Palm olein was more stable than soybean oil under the conditions of this study and produced french fries with a lower oil content. [ABSTRACT FROM PUBLISHER]

Abstract: Medium chain (MC) fatty acids, caprylic (C8:0) and capric (C10:0) were incorporated into palm olein by 1,3-specific lipase acidolysis, up to 36% and 43%, respectively, when added as mixtures or individually after 24h. It was found that these acids were incorporated into palm olein at the expense of palmitic and oleic acids, the former being larger in quantity and reduction of 18:2 was negligible. The modified palm olein products showed reduction in higher molecular weight triacylglycerols (TGs) and increase in concentration of lower molecular weight TGs compared to those of palm olein. Fatty acids at sn-2 position in modified products were: C10:0, 4%; C16:0, 13%; C18:1, 66%; and C18:2, 15.4%. DSC results showed that the onset of melting and solids fat content were considerably reduced in modified palm olein products and no solids were found even at and below 10°C and also the onset of crystallisation was considerably lowered. The cloud point was reduced and iodine value dropped from 55.4 to 38 in modified palm olein. Thus, nutritionally superior palm olein was prepared by introducing MC fatty acids with reduced palmitic acid through lipase acidolysis. [Copyright &y& Elsevier]

Abstract: Long-chain polyunsaturated fatty acids (LCPUFA) such as docosahexaenoic (DHA) and arachidonic (ARA) acids have great benefits for the development and maintenance of human brain functions. The production of structured lipid (SL) by acidolysis of palm olein with a free fatty acid mixture obtained from DHASCO® and ARASCO®, catalyzed by Novozym 435® in hexane was optimized by response surface methodology (RSM). Three independent factors chosen were substrate mole ratio of total free fatty acids to palm olein (6–18 mol/mol), reaction temperature (55–65 °C), and reaction time (12–24 h). Good quadratic models were obtained for the incorporation of DHA + ARA (response 1) and their incorporation at the sn-2 position (response 2) by multiple regression and backward elimination. The models were verified by carrying out acidolysis reaction at several random combinations of the independent factors. The optimal condition generated from the models resulted in 25.25 g/100 g total incorporation of DHA + ARA and 17.20 g/100 g DHA + ARA incorporation at the sn-2 position. The fatty acid composition of SL was comparable to that of human milk fat. The SL produced in this study has potential for use in infant formulas as well as in nutraceutical applications for pregnant women. [Copyright &y& Elsevier]

Sensory analysis is a valuable tool used to determine the effect of a formulation or process on the perception of a product. In this study, triangle tests were performed to determine differences between fried foods cooked in fresh palm olein and a fresh blend of canola oil and palm olein (50/50) and between food products fried in fresh oil and those fried in used oil. Freshness did not cause a significant difference between french fries and chicken nuggets, as evaluated by 72 nontrained judges (p > 0.05). However, the kind of oil had an effect on the sensory perception of the fried foods, in particular the flavor and texture of both products (p < 0.05). [ABSTRACT FROM AUTHOR]

The performance of palm oil as a lubricant in a cold metal forming process was tested and evaluated by carrying out plane strain extrusion experiments and experimental analyses using a visioplasticity method. In the present research, two types of refined palm oil, refined, bleached, and deodorized (RBD) palm olein and RBD palm stearin, were tested as lubricants. The workpiece material was aluminum JIS-A1050. The experiments were carried out at room temperature (22°C). Paraffinic mineral oils with varying degrees of viscosity were tested for comparison. The experiment used an extrusion apparatus in which the taper dies were facing together, with zero frictional constraint at the contact plane (corresponding to the plane plate tool) conducted, and results were compared with those extruded with lubricants. Extrusion load and surface roughness of the billets were measured and compared. The distribution of the material flow velocity and effective strain in the exit zone of the billets were calculated using the visioplasticity method, and these data were also compared. The results confirmed that RBD palm olein and palm stearin provide sufficient lubrication performance in the cold work metal forming process. [ABSTRACT FROM PUBLISHER]

Abstract: Through the application of a dynamic method, the solubility of three lipid components with different volatilities and polarities was measured in supercritical carbon dioxide (SC-CO2). Binary systems of CO2/squalene (SQ), CO2/oleic acid (OA) and CO2/pseudo-component palm olein (PO) were measured at temperatures of 313, 333 and 353K, and at a pressure range of 10–30MPa. A ternary system of CO2/SQ/PO and a quaternary system of CO2/SQ/PO/OA were also investigated at 313K and pressures of 10–25MPa. Comparison of the ternary system with the binary system showed a decrease in the solubility of SQ, with a corresponding rise in the solubility of PO. In the quaternary system, the presence of OA decreased the selectivity of SQ. The data were correlated using Chrastil’s equation in order to examine the general trend of solubility behaviour. [Copyright &y& Elsevier]

The physico-chemical characteristics of blends of palm olein and palm kernel oil which were further modified by chemical interesterification were studied. The slip melting points of non-interesterified blends were 19.7, 16.2, 14.5, 14.5 and 14.4 °C while those of the chemically interesterified blends were 17.7, 16.2, 19.8, 18.7 and 18.7 °C at 40, 30, 20, 10 and 0% palm kernel oil, respectively. Chemical interesterification lowered the solid fat content of the pure samples and blends across different temperatures except 90% palm olein at 15 °C where the solid fat content was higher than for non-interesterified samples. Palm kernel oil, palm olein and their blends before and after chemical interesterification, crystallized mainly in the β′ form. However, chemical interesterification modified the microstructure from a combination of fat particles with void regions of crystalline materials to fat particles without regions of void crystalline materials. Palm olein and palm kernel oil blends are mainly used for food preparation in Nigeria. This study has shown that there are no significant differences in the physical and chemical properties of non-chemically interesterified and chemically interesterified blends of palm olein and palm kernel oil. This implies that blending of palm olein and palm kernel oil without chemical interesterification can provide the fluidity desirable at ambient temperatures for food applications in the tropics. [ABSTRACT FROM AUTHOR]

This work presents the application of response surface methodology (RSM) to the study of the effects of three factors (temperature, percent stripping steam and the stearin/olein ratio) on the losses/transfer of fatty compounds during the steam deacidification of blends of palm oil fractions (stearin and olein) as model systems. The responses of interest were the final oil acidity and the loss of neutral oil (NOL). These experiments were unprecedented in terms of the monitoring and controlling of the process variables during the heating and stripping periods in a laboratory scale batch deodorizer. The results revealed that the oil composition was an important and statistically significant factor in the selection of more suitable processing variables, besides temperature and steam. [ABSTRACT FROM AUTHOR]

Abstract: BA (boiler ash) (empty fruit bunch ash) was used as a source of pseudo-homogeneous base catalyst for transesterification of palm olein. BA successfully transesterified palm olein at mild reaction conditions (3wt.% dried BA, 15:1 methanol:oil molar ratio, reaction temperature of 60°C and reaction time of 30min) to produce 90% methyl esters. Although BA works very well as a catalyst for transesterification, it is not reusable as the active species in the catalyst tend to leach out of the system during reaction. BA was prepared for transesterification by drying in oven at 105±2°C to constant weight. [Copyright &y& Elsevier]

The effect of dissolving β-carotene into palm olein was experimentally investigated using time-resolved thermal lens spectroscopy. The thermal diffusivity of palm olein was measured, and the dependence on the concentration of the compounds was studied. The results show an enhancement in the thermal diffusivity by increasing the quantity of β-carotene in the compounds. This behavior was interpreted on the basis of the electronic structure of the β-carotene molecule. [ABSTRACT FROM AUTHOR]

Abstract: Electron spin resonance (ESR) and spin trapping detection of radical formation showed that the oxidative stability of palm olein/fish oil mixtures increased with the amount of palm olein. Mixtures with red palm olein were less stable than were mixtures with yellow palm olein. Addition of ascorbyl palmitate and citric acid gave further reduction of radical formation, whereas no effect was observed by adding lecithins. Storage of palm olein/fish oil mixtures (4:1) at 30°C confirmed that red palm olein mixtures were less stable than were yellow palm olein mixtures. Ascorbyl palmitate together with citric acid improved the stability in both cases. The concentrations of α-tocopherol and α-tocotrienol decreased during storage, whereas β-, γ-, and δ-tocotrienols were unaffected. Ascorbyl palmitate reduced the losses of α-tocopherol and α-tocotrienol. The rate of loss of carotenoids was independent of the presence of fish oil and, except for an initial fast drop, also of the presence of ascorbyl palmitate. [Copyright &y& Elsevier]

Abstract: The cockle shell, which is available in abundance, has no any eminent use and is commonly regarded as a waste, was utilized as a source of calcium oxide in catalyzing a transesterification reaction to produce biodiesel (methyl esters). A central composite design (CCD) was used to optimize the two major influential reaction variables: catalyst and methanol amount towards purity and yield of methyl esters. The analysis of variance (ANOVA) indicated that the catalyst has a positive influence on purity but negative on the yield. Meanwhile, the methanol/oil mass ratio showed a positive effect on both purity and yield. Using CCD, the optimum reaction conditions were found to be 4.9wt.% of catalyst and 0.54:1 methanol/oil mass ratio. The prepared catalyst was capable of being reused under the suggested optimal conditions. [Copyright &y& Elsevier]

Composition and thermal profiles of the endogenous lipids of ten commercial chicken nuggets brands (NPO, ACO, AFO, APO, ASO, AMO, ARO, JOD, SMO, and SOD) were compared with those of the lipids of chicken nuggets pre-fried in lard (ALD) and palm olein (AOO) to determine the type of oil used for pre-frying of the product. The stearic acid content of the commercial brands were similar to that of the sample pre-fried in palm olein, but significantly ( p < 0.05) lower than that of the sample pre-fried in lard. The triacylglycerol (TAG) profiles of the commercial brands were similar to that of the sample pre-fried in palm olein, but distinctly different from the sample pre-fried in lard according to the dissimilarities in the contents of TAG molecules namely, PLL, POS, and PPO. Based on thermal analysis, the commercial brands of chicken nuggets could be divided into three distinguishable subgroups namely, Group-A: NPO; Group-B: ACO, AFO, APO, ASO; Group-C: AMO, ARO, JOD, SMO, SOD. While brands under group-B showed close similarity to AOO, none show any similarity to sample ALD. As any of the samples did not possess characteristics of the sample pre-fried in lard, the commercial brands of chicken nuggets of this study are recommendable for consumers whose religious restriction prevents the use of lard in food. [ABSTRACT FROM AUTHOR]

Today, the development of bio-lubricants, which are biodegradable, has become one of the most urgent research projects all over the world. In Malaysia, palm oil has shown promise as a bio-lubricant. Palm oil is eco-friendly and has a high production rate, which could fulfill the demand for a vegetable base lubricating oil. In this research, the possibility of RBD palm stearin to be used as a cold work forward extrusion was investigated with plane strain extrusion experiments. Billet material used in the present experiment was Aluminum Alloy AA5083. The metal flow of billet in the deformation area was analyzed with the visioplasticity method. From the results, we confirmed that the lubrication performance of RBD palm stearin is as effective as paraffinic mineral oil in its ability to reduce frictional constraint in a cold work extrusion. [ABSTRACT FROM AUTHOR]

The epoxidation process of palm olein (POo) was carried out by using in situ generated performic acid (HCOOOH) to produce epoxidized palm olein (EPO). HCOOOH was produced by mixing of formic acid (HCOOH) as oxygen carrier and hydrogen peroxide (H2O2) as oxygen donor in various ratio of POo: HCOOH: H2O2. The effect of HCOOH and H2O2 concentration, temperature, stirring effect and reaction time were studied. The presence of oxirane ring of EPO was characterised by fourier transformation infra-red (FTIR), proton and carbon nuclear magnetic resonance (1H-NMR and 13C-NMR) spectra. The results showed that an optimum oxirane oxygen content (OOC) value was obtained by using mol ratio of 1: 5: 2 at 150 minutes. [ABSTRACT FROM AUTHOR]

Abstract: The stability of refined, bleached and deodorised (RBD) palm olein was studied under both repeated frying and controlled heating conditions. Two different frying foods i.e. chicken nuggets and French fries were used to evaluate the oil performance under various frying conditions. Thermo-oxidative alterations were measured through various physical and chemical parameters. Total polar compounds (TPC), polymeric triglycerides (PTG), blueness (b ∗ value), chroma (C ∗ value), refractive index and viscosity increased linearly with the number of frying/heating cycles. Palmitic acid content increased and linoleic acid content decreased linearly with the number of frying cycles. No significant changes in oleic acid were detected. Thermo-oxidative reactions induced under the heating conditions were found to be faster as compared to those under the frying conditions. The PTG formed at the end of heating cycles (16.42%) were substantially higher as compared to those formed at the end of frying French fries (9.72%) and chicken nuggets (5.34%). [Copyright &y& Elsevier]

Abstract: In this contribution, the nature of particular crystal growth behavior observed in industrial dry fractionation of palm olein is further elucidated. Refined palm olein was prepared with three different concentrations of tripalmitoyl-glycerol (0.6%, 0.8% and 1%) and crystallized under stirring at 13, 15 and 17°C to study the effect of internal seeding with tripalmitoyl-glycerol (PPP) on bulk crystallization properties. Notably at 15°C, the increase in the solid fat content of the crystal suspension as function of time was heavily promoted by higher PPP-contents. The resulting crystals displayed a broad melting peak between 28 and 40°C in DSC-measurements, which suggested the presence of a solid solution in a metastable form, mainly consisting of PPP and dipalmitoyl-oleoylglycerol (POP). SAXS-measurements supported this thesis by revealing long spacings with varying length, while short spacings obtained in WAXD consistently indicated the orthorhombic subcell of a β′-polymorph. The data suggest that the internal seeding effect of PPP in palm olein, as applied in industrial crystallization, in fact relies on substantial miscibility with POP, rather than on a heterogeneous nucleation effect resulting in two separate crystalline phases. The miscibility of PPP and POP then would result in a facilitated alignment of POP-molecules in the direction of the methyl end (or lamellar) plane and higher growth rates. Secondly, a peculiar change in crystal morphology could be consistently linked with the occurrence of a sharp melting peak at 24°C in DSC, as well as with a substantial increase of the viscosity of the crystal suspension. This morphological shift concurred with an increased incorporation of palmitoyl-oleoyl-stearoylglycerol in the lattice, possibly giving rise to eutectic crystallization in lamellar crystal structures instead of the commonly observed dendritic crystals. The clarification of both phenomena provides a valuable, profound insight in the crystal growth step in the processing of edible oils. [Copyright &y& Elsevier]

Although blending polyunsaturated oil with more saturated or monounsaturated oils has been studied extensively, there is no similar information regarding the partial replacement of palm olein with olive oil (OO). Therefore the main objective of this study was to investigate the effects of OO partial replacement (0, 25, 50, 75, 90 and 100% w/w) on the chemical stability of palm olein oil (POO). The physicochemical properties of oil samples namely iodine value, peroxide value (PV), anisidine value, TOTOX value (total oxidation value, TV), free fatty acid (FFA), cloud point, color and viscosity were considered as response variables. Significant differences among the oil blend properties were determined at the significance level of P < 0.05. Apart from FFA, all the response variables were significantly influenced by type and concentration of oils. The oil blend containing 10% POO and 90% OO showed the highest TV (6.10); whereas the blend containing 90% POO and 10% OO exhibited the least TV (2.41). This study indicated that the chemical stability of oil blend significantly ( P < 0.05) increased with increasing the proportion of polyunsaturated/monounsaturated fatty acid. [ABSTRACT FROM AUTHOR]

The aim of this investigation was to evaluate the influence of certain variables of the process of deep fat frying on the lipid profile of the fat fraction of the potato type "french" (Solanum tuberosum) using palm oil. This marked the first fat fraction of both the processing type and the oil used, through the evaluation of various physicochemical parameters, using the method of AOAC and the Standard COVENIN. We identified variables that influenced the process during frying of potatoes, using an experimental design of type 3 * 2², evaluating factors such as the reuse of the matrix fat (1st, the 4th and the 8th fry), temperature (150° and 180 °C) and method of food peeling (chemical and manual), studying the content of polar compounds as an indicator of the deterioration of the fat present in the potato, finding that oil reuse and peeling method significantly influenced in a positive manner, and that the temperature has a negative influence on the absorption of polar compounds in potato chips (α: 0.05). [ABSTRACT FROM AUTHOR]

Abstract: Chemical interesterification is an important technological option for the production of fats targeting commercial applications. Fat blends, formulated by binary blends of palm stearin and palm olein in different ratios, were subjected to chemical interesterification. The following determinations, before and after the interesterification reactions, were done: fatty acid composition, softening point, melting point, solid fat content and consistency. For the analytical responses a multiple regression statistical model was applied. This study has shown that blending and chemical interesterifications are an effective way to modify the physical and chemical properties of palm stearin, palm olein and their blends. The mixture and chemical interesterification allowed obtaining fats with various degrees of plasticity, increasing the possibilities for the commercial use of palm stearin and palm olein. [Copyright &y& Elsevier]

The objective of this study was to compare two oils with different polyunsaturated/saturated (P/S) fatty acid ratios, refined olive oil (P/S 0.75) and palm olein (P/S 0.25), in frying French fries. The chemical qualities of the oil residues extracted from the French fries were assayed for five consecutive batches fried at 1-h intervals. The levels of total polar compounds, free fatty acids, p-anisidine value and phytosterol oxidation products (POPs) were elevated in French fries fried in both oils. The level of total polar compounds increased from 4.6 in fresh refined olive oil to 7.3% in final batches of French fries. The corresponding figures for palm olein were 9.8–13.8%. The level of free fatty acid in fresh refined olive oil increased from 0.06 to 0.11% in final products. These figures for palm olein were 0.04–0.13%. The p-anisidine value increased from 3.7 to 32.8 and 2.5 to 53.4 in fresh oils and in final batches of French fries in refined olive oil and palm olein, respectively. The total amount of POPs in fresh refined olive oil increased from 5.1 to 9.6 μg/g oil in final products. These figures were 1.9 to 5.3 μg/g oil for palm olein. [ABSTRACT FROM AUTHOR]

Murraya koenigii leaf extract antioxidant potentials were evaluated in palm olein using accelerated oxidation storage and deep-frying studies at 180°C for up to 40 h. The extracts (0.2%) retarded oil oxidation and deterioration significantly (P<0.05), slightly less effectively than 0.02% butylated hydroxytoluene in tests such as the peroxide value, anisidine value, iodine value, free fatty acid, Oxidative Stability Index, and polar and polymer compound content. Sensory evaluation on French fries indicated that the extract was useful in improving colour, flavour and overall acceptability and the quality of the fried product. All samples were more acceptable by panellists, especially after the 40th hour frying, compared with those similarly fried in the control oils and the oil containing butylated hydroxytoluene. M. koenigii leaf extract, had a polyphenol content of 109.5±0.3 mg gallic acid equivalents/g extract, and contain a heat-stable antioxidant that could be a natural alternative to synthetic antioxidants for the industry. [ABSTRACT FROM AUTHOR]

Physicochemical, textural and viscoelastic properties of palm diacylglycerol (PDG) bakery margarines (DOS720, DOS721 and DOS711) and commercial margarine (CM) throughout a 3-month storage period were evaluated and compared. All the margarines had significant ( P < 0.05) increments in slip melting point (SMP), solid fat content (SFC) and hardness during storage with CM having the highest overall increment followed by margarines DOS711, DOS 721 and DOS720. The smaller increments are mainly due to the ability of PDG to delay polymorphic transformation from β′ to β form. In terms of viscoelastic properties, all margarines had a higher degree of firmness which may probably be due to rearrangement of the fat crystals into a three-dimensional scaffolding network upon storage. In terms of melting behavior, storage has no effects on all margarines with the exception of margarine DOS711. The melting behavior of margarine DOS711 displayed a probability of oil exudation during storage. As for polymorphic transformation, CM had the earliest polymorphic transformation with only β crystals after 8 weeks of storage. PDG bakery margarines managed to retard the transformation to more than 10 weeks of storage for DOS711 and 12 weeks of storage for DOS720 and DOS721. [ABSTRACT FROM AUTHOR]

Abstract: A flow injection analyzer for the determination of total oxidation value (TOTOX) in palm oleins was developed based on the sequential determination of peroxide value (PV) and anisidine value (AV) using a common triiodide () potentiometric detector. The PV and AV parameters were sequentially determined by manipulating a switching valve. The mixing of the oil and reagents was effective by applying a short vortex (30s). The TOTOX value is obtained from the potentiometric readings of PV and AV (TOTOX=2PV+AV). Using palm olein as standard, the method gives TOTOX value that is linear over 1.7–79.0 with a detection limit of 1.64. The sampling frequency is about 60h−1. Twenty aged and thermally stressed palm olein samples were analyzed and good correlations (r 2 =0.9852) were found between the proposed FIA and the official methods. [Copyright &y& Elsevier]

The antioxidative properties of Curcuma longa (turmeric) leaf extract were evaluated in refined, bleached and deodorized (RBD) palm olein using accelerated oxidation and deep frying studies at 180 °C for up to 40 h. The extract was capable of retarding oil oxidation and deterioration significantly ( P < 0.05) at 0.2% concentration, better than 0.02% BHT for the Oxidative Stability Index (OSI) in an accelerated oxidation study and also the peroxide value in deep frying studies. In sensory evaluation, the French fries were acceptable and were not significantly different ( P < 0.05) from one another for color, oiliness and crispiness throughout the 40-h frying study. Curcuma longa leaf extract, which had a polyphenol content of 116.3 ± 0.2 mg/g, possessed heat-stable antioxidant properties and may be a good natural alternative to existing synthetic antioxidants in the food industry. [ABSTRACT FROM AUTHOR]

The application of immobilized enzyme in packed-bed reactor is gaining interest in the industry as it offers advantages over conventional chemical reactions. However, external mass transfer limitation is significant in immobilized enzyme packed-bed reactors, especially at large scales. This study aimed to develop an external mass transfer model for immobilized lipase (EC 3.1.1.3) during the hydrolysis of palm olein. A mass transfer correlation model of the form JD = KRen-1 was developed based on the literatures. The Colburn factor,JD, which is a function of Reynolds and Schmidt numbers, can be related to the external mass transfer coefficient, κm. The values of K and n were determined by conducting experimental work at different mass flow rates. It was found that the values of K and n are 0.093 and 0.5, respectively. Since the average mass transfer coefficients can be correlated in terms of dimensionless groups which characterize the flow conditions, this model can be used for reactor scale-up design. [ABSTRACT FROM AUTHOR]

The effects of vegetable fats in low-calorie dates ice cream were studied. Fourteen different formulations were optimized by ‘simplex lattice design’. Three types of fat (palm mid-fraction, palm olein and rice bran oil) were chosen to investigate their particle size distribution, melting resistance, amount of protein in the aqueous phase, colour, viscosity, total solids, percentage of overrun, fat and calorie value in ice cream. Statistical significance was determined by using analysis of variance and compared with the Duncan multiple range test using the SAS program. The significance level was 95% (P  = 0.05). The types of fat used in an ice cream formulation have an impact on the colour, particle size diameter, viscosity and caloric value. A high percentage of palm mid-fraction (> 12%) gave a high intensity of brightness, but less redness and yellowness, while a high percentage of palm olein and rice bran oil gave high intensity of redness and yellowness. Moreover, viscosity was associated with formulations characterized by a high solid fat content. The more unsaturated and the longer the fatty acid chains of the vegetable fat used in the formulation, the more pronounced was the fat globule destabilization. However, the effect of the different fats on melting resistance was less pronounced. [ABSTRACT FROM AUTHOR]

Abstract: A packed-bed reactor (PBR) system using immobilized lipase PS as biocatalyst was developed for continuous monoacylglycerols (MAG) production. The condition for continuous MAG production using immobilized lipase PS (IM-PS) of 1.5g (550U) in PBR (0.68cm i.d., 25cm long) was optimized. The effect of molar ratio of glycerol to palm olein, water content in glycerol and residence time on MAG production was investigated. The optimal glycerol to palm olein molar ratio and water content in glycerol were 12:1 and 10% (w/w), respectively. The yield of MAG increased with increasing residence time. At a residence time of 7.5h gave the highest yield of MAG of 60%. The long-term operation gave the highest yield of MAG 61.5% at 24h of the operation time with the productivity of 1.61gMAG/day. A half-life of the long-term process was 35 days of the operation time with the productivity of 0.81gMAG/day. Furthermore, the large scale of MAG production was performed continuously with IM-PS of 15g (5500U) in PBR (1.5cm i.d., 50cm long). The highest yield of MAG in large-scale operation of 70.1% and the 11-fold increasing in productivity of 18.3gMAG/day were obtained at 24h of the operation time. [Copyright &y& Elsevier]

Chemical transesterification and blending techniques were used for producing zero trans fats suitable for use as Iranian vanaspati. Triple blends of palm olein (POo), rapeseed (RSO) and sunflower oil (SFO) were subjected to two different treatments: (i) blending and then transesterification (BT) and (ii) transesterification of pure POo before blending with RSO and SFO (TB). The changes in slip melting point (SMP), solid fat content (SFC), carbon number (CN) triacylglycerol (TAG) composition, induction period (IP) of oxidation at 120 °C and IP of crystallisation at 20 °C of blends before and after treatments were investigated. Both BT and TB methods resulted in an increase in the CN48 TAG molecules, SMP and SFC, and a decrease in the IP of oxidation and crystallisation of initial blends. Samples made by TB method had higher CN48 TAG content, SMP, SFC and IP of oxidation, and lower IP of crystallisation than those made by BT method. Correlation between SFC at 20 °C and saturated fatty acid (SFA) content of the treated blends indicated that the SFA must be higher than 33.1% and 26.8% for BT and TB methods, respectively, to obtain fats suitable for use as vanaspati. [ABSTRACT FROM AUTHOR]

Abstract: Partial hydrolysis using Lipozyme RMIM lipase in a solvent-free system was used to produce a diacylglycerol (DAG)-enriched palm olein. Response surface methodology (RSM) was applied to model and optimize the reaction conditions namely water content (30–70wt% of enzyme mass), enzyme load (5–15wt% of oil mass), reaction temperature (45–85°C) and reaction time (6–16h). Well fitting models were successfully established for both DAG yield (R 2 =0.8788) and unhydrolysed triacylglycerol (TAG) (R 2 =0.8653) through multiple linear regressions with backward elimination. Chi-square test indicated that there were no significant (P >0.05) differences between the observed and predicted values for both models. All reaction conditions had positive effects on DAG yield and negative effects on unhydrolysed TAG. Optimal reaction conditions were: 50wt% water content, 10wt% enzyme load, 65°C of reaction temperature and 12h of reaction time. The process was further up-scaled to a 9kg production in a continuous packed bed bioreactor. Results indicated that upscaling was possible with a similar DAG yield (32wt%) as in lab scale. Purification of the DAG oil using short path distillation yielded a DAG-enriched palm olein with 60wt% DAG and 40wt% TAG which is suitable for margarine, spread or shortening applications. [Copyright &y& Elsevier]

Refined palm olein was dry fractionated via three different cooling programs on laboratory-scale fractionation equipment. The enrichment and depletion of the main triacylglycerols in the liquid and solid phase was plotted as a function of the crystallization degree of the oil. It was shown that for the given conditions and palm olein composition, the initial crystals mainly consisted of PPP, diacylglycerols, POP and PLP. At higher crystallization degrees, a sharp viscosity increase in the crystal suspension was primarily related to an obvious decrease of POP but also of POS in the recovered superolein, while the general crystallization rate of the system remained unchanged. Rather than a change in crystallization rate of POP, a change in the ratio between the crystallizing monounsaturated triacylglycerols is linked with the high viscosity of the crystal slurry. For a comparable degree of crystallization, the superolein of the more viscous crystal slurry, obtained through a membrane press filtration up to 15 bar, was more unsaturated than the superolein filtered from the less viscous slurry. Consequently, the high unsaturation in the corresponding soft palm mid fraction is only the result of an incomplete phase separation, and not due to an increased intersolubility of unsaturated triacylglycerols in the crystals. [ABSTRACT FROM AUTHOR]

Abstract: Changes in the rheological properties during crystallisation and in the crystal size and morphology of blends containing rapeseed oil with varying percentages of palm stearin (POs) and palm olein (POf) have been studied. The crystals formed from all three blends were studied by confocal laser scanning microscopy, light microscopy and environmental scanning electron microscopy, which revealed the development of clusters of 3–5 individual elementary “spherulites” in the early stages of crystallisation. The saturated triacylglycerol content of the solid crystals separated at the onset of crystallisation was much greater than that in the total fat. Fat blends with a higher content of palm stearin had a more rapid nucleation rate when observed by light microscopy, and this caused an earlier change in the rheological properties of the fat during crystallisation. Using a low torque amplitude (0.005Pa, which was within the linear viscoelastic region of all samples studied) and a frequency of 1Hz, the viscoelastic properties of melted fat during cooling were studied. All samples, prior to crystallisation, showed weak viscoelastic liquid behaviour (G″, loss modulus >G′, storage modulus). After crystallisation, a more “solid like” behaviour was observed (G′ similar to or greater than G″). The blend having the highest concentration of POs was found to have the earliest onset of crystallisation (27% w/w POs; 12mins, 22% w/w POs; 13.5mins, 17% w/w POs, 15mins, respectively). However, there were no significant differences in the time to the point when G′ became greater than G′ among the three blends. [Copyright &y& Elsevier]

Abstract: Kinetic study of monoacylglycerol production by glycerolysis of palm olein using immobilized lipase has been investigated. A mathematical model took into account mechanism of glycerolysis reaction using palm olein as substrate was developed. The kinetic parameters were estimated by fitting experimental data of glycerolysis reaction of palm olein by immobilized lipase PS on Accurel EP-100. There was a good agreement between experimental results and those predicted by proposed model equations under various enzyme, water, glycerol and palm olein concentrations. From proposed model equations, the synergic effect of glycerol and palm olein concentrations was simulated. The simulation results show that the behavior of high substrate concentrations obtained high initial production rates but low yields of monoacylglycerol. Thus, at high concentrations of palm olein and glycerol of 7.16 and 19.14mM, respectively, high initial production rate of monoacylglycerol of 0.338mMh−1 and acceptable yield of 82% were obtained. On the other hand, the highest yield of monoacylglycerol of 100% was obtained at comparatively low palm olein concentration of 2.39mM and excess glycerol concentration of 19.14mM. [Copyright &y& Elsevier]

Abstract: A flow injection analysis (FIA) procedure for the determination of anisidine value (AV) in palm olein using a triiodide detector is described. Undiluted oil sample and chloramine-T reagent were added to a reaction chamber, and reaction was accelerated by applying a short vortex action (typically for 30s). After allowing the emulsified oil phase to be separated from the aqueous phase (bottom layer), an aliquot of the aqueous phase (containing unreacted chloramine-T) was aspirated into a carrier stream that contained I− where the chloramine-T oxidized the I− to form I3 − which was finally detected by a flow-through triiodide potentiometric detector. Variables that affect the FIA signals such as size of the reaction chamber, oil and reagent flow rates, chloramine-T concentration, vortex time, time for phase separation, carrier stream pH and injected volume were studied. The optimized FIA procedure is linear over 1.0–23.0AV. The method exhibits good repeatabililty (R.S.D. of ±3.16% (n =4) for the determination of 5.0AV) and a sampling rate of 40 samples per hour was achieved. Good correlation (r 2 =0.996 (n =4)) between the proposed method and the manual American Oil Chemists’ Society procedure was found when applied to the determination of twenty different types of palm olein samples. [Copyright &y& Elsevier]

Abstract: The performance of a nonporous composite polymeric membrane was evaluated for processing crude palm oil and palm olein under both undiluted and hexane-diluted conditions focusing on the refining aspects besides retention of nutrients. The phospholipid contents of crude palm oil and palm olein were low and probably very close to the critical micelle concentration necessitating the use of a nonporous membrane for its effective removal. Membrane showed very high selectivity between triglycerides and phospholipids even under hexane-diluted conditions and the phospholipid rejection was nearly complete (95–100%). The membrane did not exhibit any appreciable selectivity towards carotenes and antioxidants (tocopherols and tocotrienols) that enabled their retention in the processed oil. Fatty acid composition of palm oil, which differs from other crude vegetable oils, seems to play some role in the permeation of tocopherols along with triglycerides. Oil flux improvement by one order of magnitude at a very low dilution with hexane (1:1) without affecting the membrane performance is an attractive feature, offering greater productivity. [Copyright &y& Elsevier]