Melting and Solidification Properties of Palm Kernel Oil,Tallow, and Palm Olein Blends in the Preparation of Shortening

Ternary systems composed of palm kernel oil (PKO), tallow, and palm olein (POo) were studied in terms of their physical properties such as solid fat content (SFC), melting characteristics by DSC and polymorphism by X-ray diffraction. Ternary phase behavior was analyzed with isosolid diagrams. The results showed that as the POo content of the blends was increased the SFC value decreased, while the increase of tallow content increased the SFC value. Eutectic effects within the ternary system were confirmed from the deviation of the measured SFC from the calculated SFC for corresponding thermodynamically ideal blends. The deviation reached a maximum when the amounts of PKO and POo are both about 45%. X-ray diffraction results showed that addition of PKO into the blends promoted stabilization in the β′ crystalline form.     

Frying Quality Characteristics of French Fries Prepared in Refined Olive Oil and Palm Olein

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.     

Comparison of the Frying Stability of Standard Palm Olein and Special Quality Palm Olein

The main goal of this work was to investigate the stability of standard palm olein (SPOo) and special quality palm olein (SQPOo) under continuous frying conditions. The rate of free fatty acid (FFA) formation was slightly higher for SPOo than SQPOo during 56 h of frying. An equilibrium state was reached at around 40 h for SPOo and 32 h for SQPOo, whereby FFA varied within a narrow range of 0.30–0.32 and 0.22–0.25%, respectively. Smoke point of SPOo and SQPOo progressively dropped from 212 to 184 °C and from 227 to 191 °C. Tocols of SPOo and SQPOo declined from 550 to 273 mg kg⁻¹ and from 720 to 447 mg kg⁻¹ after 56 h of frying, respectively. Oxidative stability of both oils decreased after the successive frying. Induction time of SPOo dropped from 22.3 to 14.9 h while SQPOo decreased from 25.5 to 18.3 h. Polar and polymer compounds increased as frying progressed. The SPOo had higher levels of polar compounds, averaging 11.8%, compared to the 10.2% in SQPOo. However, SPOo had lower levels of polymer compounds compared to SQPOo, averaging 2.1 and 2.5%, respectively. Hence, this work confirms that frying performance using SPOo was comparable to SQPOo for use in industrial production of snack foods (potato chips).     

Processing of Palm Kernel Oil

By the end of the century palm kernel (PK) oil is forecast to rank fifth in volume of world trade in oils, only slightly behind coconut oil. PK oil received by Malaysian refiners is of good quality, typically below 2% in free fatty acids, and is easily refined. PK oil is fractionated to give a higher melting fraction (stearin) and a lower melting fraction (olein). The various processes used are described. PK oil, olein or stearin are also hydrogenated to give a range of products ranging in melting point from about 24 to 44°C. PK oil and olein are interesterified alone or in blends with a non-lauric oil to give products with improved melting properties and utility. The utilisation of PK oil in the main application areas of confectionery fats, non-dairy/imitation dairy products, biscuit creams, industrial margarines, nut roasting and spray oils are discussed.     

Frying Stability of Canola Oil Blended with Palm Olein, Olive, and Corn Oils

The fatty acid composition, peroxide value (PV), acid value (AV), iodine value (IV), total tocopherols (TT) content, and total phenolics (TP) content of canola oil (CAO), palm olein oil (POO), olive oil (OLO), corn oil (COO), and the binary and ternary blends of the CAO with the POO, OLO, and COO were determined. The blends were prepared in the volume ratios of 75:25 (CAO/POO, CAO/OLO, CAO/COO) and 75:15:10 (CAO/POO/OLO, CAO/POO/COO). The CAO and its blends were used to fry potato pieces (7.0 × 0.5 × 0.3 cm) at 180 °C. During the frying process, the total polar compounds (TPC) content, AV, oil/oxidative stability index (OSI), and color index (CI) of the CAO/blends were measured. In general, frying stability of the CAO was significantly (P < 0.05) improved by the blending, and the frying performance of the ternary blends was found to be better than that of the binary blends.     

Use of the SAW Sensor Electronic Nose for Detecting the Adulteration of Virgin Coconut Oil with RBD Palm Kernel Olein

An electronic nose (zNose™) was applied to the detection of adulteration of virgin coconut oil. The system, which is based on a surface acoustic wave sensor was used to generate a pattern of volatile compounds present in the samples. Virgin coconut oil was mixed with refined, bleached and deodorized palm kernel olein at a level of adulteration from 1 to 20% (wt/wt). Adulterant peaks were identified from the chromatogram profile and fitted to a curve using linear regression. The best relationship (R ² = 0.91) was obtained between the peak tentatively identified as methyl dodecanoate and the percentage of palm kernel olein added. Pearson’s correlation coefficients (r) of 0.92 and 0.89 were obtained between adulterant peak methyl dodecanoate and of the iodine and peroxide values, respectively. Principal component analysis (PCA) was used to differentiate between pure and adulterated samples. The PCA provided good differentiation of samples with 74% of the variation accounted for by PC 1 and 17% accounted for by PC 2. Pure samples formed a separate cluster from all of the adulterated samples.     

Blending of Palm Mid-Fraction,Refined Bleached Deodorized Palm Kernel Oil or Palm Stearin for Cocoa Butter Alternative

This study evaluated the physicochemical properties of palm mid‐fraction (PMF), refined bleached deodorized palm kernel oil (RBDPKO) and refined bleached deodorized palm stearin (RBDPS) as binary mixtures in terms of their fatty acid compositions (GC), triacylglycerols (HPLC), solid fat contents (p‐NMR), melting behaviors (DSC) and polymorphisms (XRD) for cocoa butter (CB) alternative formulations. All the PMF/RBDPKO and RBDPS/RBDPKO blends showed mixtures of short/long‐chain fatty acids with corresponding triacylglycerols. 10–70 % PMF in RBDPKO showed a eutectic effect between 20 and 30 °C. However, a monotectic effect was observed at 10–15 °C for 20–40 % PMF in RBDPKO and 40–80 % of RBDPS in RBDPKO. For PMF/RBDPS blends, a monotectic effect was observed at less than 30 °C. Broad endotherms at 20–38 °C were observed for 30–50 % RBDPS in RBDPKO which are closer to CB, with polymorphs of β′₁ > β′₂ ? β₂ based on XRD analysis. 50–80 % PMF in RBDPS exhibited significantly higher contents of long‐chain fatty acids with the exception of stearic and lower constituents of monounsaturated triacylglycerols compared to CB. Broad endotherms were observed at 20–38 °C for 50–80 % PMF in RBDPS which are closer to CB, with β′₁ ? β′₂ > β₂. Therefore, 20–40 % PMF in RBDPKO, 30–50 % RBDPS in RBDPKO and 50–80 % PMF in RBDPS could be used as CB substitutes because of their comparable physicochemical behaviors.     

Evaluation of the Oxidative Stability of Diacylglycerol-Enriched Soybean Oil and Palm Olein Under Rancimat-Accelerated Oxidation Conditions

The oxidative stability of diacylglycerol (DAG)-enriched soybean oil and palm olein produced by partial hydrolysis using phospholipase A1 (Lecitase Ultra) and molecular distillation was investigated at 110 °C by the Rancimat method with and without addition of synthetic antioxidants. Compared with triacylglycerol oils, the DAG-enriched oils displayed lower oxidative stability due to a higher content of unsaturated fatty acids and a lower level of tocopherols. With the addition (50–200 mg/kg) of tert-butylhydroquinone (TBHQ) or ascorbyl palmitate (AP), the oxidative stability indicated by induction period (IP) of these DAG-enriched oils under the Rancimat conditions was improved. The IP of the diacylglycerol-enriched soybean oil increased from 4.21 ± 0.09 to 12.64 ± 0.42 h when 200 mg/kg of TBHQ was added, whereas the IP of the diacylglycerol-enriched palm olein increased from 5.35 ± 0.21 to 16.24 ± 0.55 h when the same level of AP was added. Addition of TBHQ, alone and in combination with AP resulted in a significant (p ≤ 0.05) increase in oxidative stability of diacylglycerol-enriched soybean oil. AP had a positive synergistic effect when used with TBHQ.     

Cocoa Butter Alternatives from Enzymatic Interesterification of Palm Kernel Stearin,Coconut Oil,and Fully Hydrogenated Palm Stearin Blends

Structured lipids (SL) were produced from enzymatic interesterification (EIE) of palm kernel stearin (PKS), coconut oil (CNO), and fully hydrogenated palm stearin (FHPS) blends in various mass ratios. The EIE reactions were performed at 60 °C for 6 hours using immobilized Lipozyme RM IM with a mixing speed of 300 rpm. The physicochemical properties, crystallization and melting behavior, solid fat content (SFC), crystal morphology and polymorphism of the physical blends (PB), and the SL were characterized and compared with commercial cocoa butter and cocoa butter alternatives (CBA). EIE significantly modified the triacylglycerol compositions of the fat blends, resulting in changes in the physical properties and the crystallization and melting behavior. SFC and slip melting point of all SL decreased from those of their counterpart PB. In particular, SL obtained from EIE of blends 60:10:30 and 70:10:20 (PKS:CNO:FHPS) exhibited a high potential to be used as trans-free CBA as they showed similar melting ranges, melting peak temperatures, and SFC curves to the commercial CBA with fine needle-like crystals and desirable β' polymorph.     

Drying Characteristics of Oil Palm Kernels

ABSTRACT

The drying characteristics of a single oil palm kernel suspended in a drying tunnel is studied. Luikov's unsteady state simultaneous heat and mass transpon equations are proposed as the governing equations. The model is simulated using the explicit and modified implicit Crank Nicholson finite difference algorithms. The desorption isotherms of the kernel warj determined using an environmental chamber and the data generated was found to fit the Hasley's and Henderson's equations well. The mass diffusion coefficient was determined by using a distributed system parameter identification technique where a weighted least square criterion between model and experimental average moisture content and temperature profiles is optimized using the Lagrangian algorithm within the constraints of the governing equations. The simulated parameter estimated drying characteristics were found to be in good agreement with experimental values.     

Enzymatic Glycerolysis of Palm and Palm Kernel Oils

Glycerolysis of palm and palm kernel oils were carried out using commercial lipases from Candida antarctica (Novozym 435) and Mucor miehei (Novozym 388) as catalyst (500 units lipase/g oil) at 40°C and with an oil:glycerol molar ratio of 1:2 in a solvent-free system. Novozym 435 catalyzed the glycerolysis of palm and palm kernel oils giving reaction products in similar compositions. Partial acylglycerols contents of the glycerolysis products obtained from palm and palm kernel oils were 64% (wt) and 66% (wt), respectively. However, partial acylglycerols contents of the glycerolysis products obtained from palm and palm kernel oils conducted with Novozym 388 as catalyst at the same conditions were 44% (wt) and 56% (wt), respectively. On the other hand, free fatty acid contents of the glycerolysis products of palm and palm kernel oils obtained using Novozym 388 were higher, 25–30% (wt), than those obtained by Novozym 435, 4–5% (wt). The monoacylglycerols fraction with the highest content of oleic acid, 62.7% (wt), was obtained from the palm kernel oil glycerolysis reaction catalyzed by Novozym 435.     

Enzymatic Glycerolysis of Palm and Palm Kernel Oils

Glycerolysis of palm and palm kernel oils were carried out using commercial lipases from Candida antarctica (Novozym 435) and Mucor miehei (Novozym 388) as catalyst (500 units lipase/g oil) at 40°C and with an oil:glycerol molar ratio of 1:2 in a solvent-free system. Novozym 435 catalyzed the glycerolysis of palm and palm kernel oils giving reaction products in similar compositions. Partial acylglycerols contents of the glycerolysis products obtained from palm and palm kernel oils were 64% (wt) and 66% (wt), respectively. However, partial acylglycerols contents of the glycerolysis products obtained from palm and palm kernel oils conducted with Novozym 388 as catalyst at the same conditions were 44% (wt) and 56% (wt), respectively. On the other hand, free fatty acid contents of the glycerolysis products of palm and palm kernel oils obtained using Novozym 388 were higher, 25-30% (wt), than those obtained by Novozym 435, 4-5% (wt). The monoacylglycerols fraction with the highest content of oleic acid, 62.7% (wt), was obtained from the palm kernel oil glycerolysis reaction catalyzed by Novozym 435.     

Margarines Produced From Rice Bran Oil and Fractionated Palm Stearin and Their Characteristics During Storage

Rice bran oil (RBO) usage in Southeast Asia is increasing. The purpose of this study was to incorporate RBO in margarine as a replacement for common oils such as soybean oil. The physicochemical properties of blends of RBO and fractionated palm stearin (FPS) at eleven different weight ratios (from 0:100 to 100:0) were characterized. Results showed that fat blends with ratios of 10:90, 20:80, and 30:70 RBO:FPS were semisolid at ambient temperature, with solid fat contents and a crystal morphology similar to commercial margarine fats. Blends containing ≤30% RBO were made into margarines and compared against commercial margarine over 8 weeks of storage. The margarine with a 20:80 RBO:FPS fat phase was stable against coalescence and phase separation while demonstrating acceptable spreadability and whippability at ambient temperature. Fat crystals in this blend were in the β′ polymorph at all time points during storage, which is a desired characteristic in margarine. This study showed that RBO may be effectively used for margarine production.     

棕榈仁油取代椰子油制皂的应用研究

棕榈仁油和椰子油成分大致相似。通过成品分析,采用棕榈仁油制成的皂基质量指标符合标准要求,完全可以代替椰子油使用,同时能够提高经济效益。     

Cocoa Butter Substitute (CBS) Produced from Palm Mid-fraction/Palm Kernel Oil/Palm Stearin for Confectionery Fillings

This study investigated the physicochemical properties of ternary mixtures of palm mid-fraction (PMF):refined bleached deodorized palm kernel oil (RBDPKO):refined bleached deodorized palm stearin (RBDPS) for cocoa butter substitute (CBS). Fatty acid constituents, triacylglycerol constituents, solid fat contents (SFCs), melting behavior, polymorphism and crystal morphology were determined using gas chromatography (GC), high-performance liquid chromatography (HPLC), differential scanning calorimetry (DSC), pulsed nuclear magnetic resonance (p-NMR), X-ray diffraction (XRD) and polarized light microscopy (PLM), respectively. Eight blends of various ratios of ternary mixtures were investigated based on the previously studied binary fat mixtures. The composition of palmitic (P) and oleic (O), POP, and crystal morphology (size and shape) of the PMF/RBDPKO/RBDPS [14.9/59.6/25.5 (%w/w)] mixture were comparable to cocoa butter (CB), while its melting profile (18.5 and 37 °C), SFC at 20 °C and polymorphism were different from CB. The iso-solid diagrams of the mixture displayed a monotectic effect at 20–25 °C. Therefore, the 14.9/59.6/25.5 PMF/RBDPKO/RBDPS mixture could be used as a CBS in confectionery fillings because of the crystal morphology and monotectic behaviors comparable to those of CB.     

Application of FTIR Spectroscopy for the Determination of Virgin Coconut Oil in Binary Mixtures with Olive Oil and Palm Oil

Rapid Fourier transform infrared (FTIR) spectroscopy combined with attenuated total reflectance (ATR) was applied for quantitative analysis of virgin coconut oil (VCO) in binary mixtures with olive oil (OO) and palm oil (PO). The spectral bands correlated with VCO, OO, PO; blends of VCO and OO; VCO and PO were scanned, interpreted, and identified. Two multivariate calibration methods, partial least square (PLS) and principal component regression (PCR), were used to construct the calibration models that correlate between actual and FTIR-predicted values of VCO contents in the mixtures at the FTIR spectral frequencies of 1,120–1,105 and 965–960 cm⁻¹. The calibration models obtained were cross validated using the “leave one out” method. PLS at these frequencies showed the best calibration model, in terms of the highest coefficient of determination (R ²) and the lowest of root mean standard error of calibration (RMSEC) with R ² = 0.9992 and RMSEC = 0.756, respectively, for VCO in mixture with OO. Meanwhile, the R ² and RMSEC values obtained for VCO in mixture with PO were 0.9996 and 0.494, respectively. In general, FTIR spectroscopy serves as a suitable technique for determination of VCO in mixture with the other oils.     

Red Palm Olein: Characterization and Utilization in Formulating Novel Functional Biscuits

Functional biscuits were formulated by replacing white shortening (WS) by red palm olein (RPOL) at 20, 40, 60, 80 and 100%. Sensory evaluation of fresh biscuits indicated that all RPOL levels were significantly as acceptable as or superior to the control. Consequently, two superior RPOL levels (40 and 60%) were chosen for further investigation along with the control. Biscuits made from 40% WS + 60% RPOL exhibited significantly the lowest values regarding water loss during baking, volume before baking, specific volume, specific lightness, water activity and shearing force. Triacylglycerol and fatty acid composition of formulated biscuits resembled their counterparts for RPOL. These biscuits contained 1.8 times more tocopherols and tocotrienols and 10.4–14.8 times more carotenes than the control. Meanwhile, packaged biscuits were able to be stored at room temperature in the light for not less than 6 months without any deterioration in their quality.     

Process Technology for the Production of Micronutrient Rich Red Palm Olein

Crude palm oil (CPO) is the richest natural source of carotenes that are destroyed in the conventional processing. There is a growing demand for nutritional products containing bioactive constituents externally fortified or preserved through modified process. A commercially viable process for the production of red palm olein (RPOn) rich in carotenes, tocols and sterols has been developed at pilot scale. The process developed involved neutralization of CPO followed by crystallization at controlled rate of cooling and deodorization of the resultant neutralized and winterized palm olein (WPOn) under controlled conditions of temperature and high vacuum. Analytical data related to micronutrients at each process step was monitored. The RPOn thus produced had not more than 0.25% of free fatty acids (FFA) and it retained more than 80% of the carotenes, about 85% of tocols and 65% of sterols originally present in the CPO. The physico-chemical characteristics of RPOn revealed that it is nutritionally of superior quality compared to that of the commercial refined bleached deodorized (RBD) palm olein currently available in the market. The carotenes, tocols and sterols profile of RPOn by HPLC showed that they were retained in their natural forms.     

Odor Significance of the Volatiles Formed During Deep-Frying With Palm Olein

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.     

Performance of Choline-Based Deep Eutectic Solvents in the Extraction of Tocols from Crude Palm Oil

Deep eutectic solvents are emerging green solvents that have potential in many separation processes. This study investigates the performance of choline‐based deep eutectic solvents in the extraction of tocopherols and tocotrienols (collectively known as tocols) from palm oil, a major natural source of tocols. Deep eutectic solvents comprised of choline chloride salt and selected carboxylic acids as hydrogen bond donors were prepared and used in the extraction of tocols from crude palm oil by liquid–liquid extraction. Tocols concentration in the extracted product was at least double that in the control (8671 mg/kg compared to 3285 mg/kg, respectively). Increasing the amount of the deep eutectic solvents increased the tocols concentration in the extracted product up to 18,525 mg/kg, but the yields lowered from 4 % to less than 1 %. The tocols profile was significantly improved by the increase of the tocotrienols fraction in the products from 80.8 to 99.8 %. This study showed that unique interaction between the selected deep eutectic solvents with the tocols make it possible to selectively separate individual tocols in palm oil, where products with fractions rich in tocotrienols and low in tocopherols (particularly α‐tocopherol) are favorable.