Polymorphism of palm oil and palm oil products

Palm oil, palm stearin, hydrogenated palm oil (IV 27.5) and hydrogenated palm olein (IV 28) were crystallized at 5°C, temperature cycled between 5 and 20°C, and kept isothermally at 5°C for 36 days. The polymorphic state of the fats was monitored by X-ray diffraction analysis. Soft laser scanning of X-ray films was used to establish the increase inβ crystal content. Palm stearin was least stable in theβ′ form, followed by palm oil. The hydrogenated oils were very stable in theβ′ form. Differential scanning calorimeter (DSC) analysis was used to complement the X-ray data.     

Commercially available alternatives to palm oil

Since several years there has been a demand for food products free of palm oil, noticeable in the Western European market. Alternatives based on liquid oils, fully hydrogenated fats, and exotic fats like shea and sal etc., have been developed by the research groups of several specialty oils and fats suppliers. This article describes the advantages and disadvantages of those products and compares them to similar products based on palm oil. It is also discussed how reasonable the replacement of palm products would be, since sustainable and 3‐MCPD/glycidolester‐reduced palm based specialty oils are also available on the market.     

Dehulling of palm kernel of oil palm (Elaeis guineensis) to obtain superior-grade palm kernel flour and oil

A novel method has been developed for the removal of the thin, dark-brown skin, called testa, from the palm kernel of the oil palm (Elaeis guineensis) by chemical treatment. Studies carried out for this purpose included physical or mechanical means, dry or wet heat, solvents and other chemicals. Of the procedures tried, treatment with hydrochloric acid (HCl) resulted in complete removal of the testa, producing a pearl-white palm kernel. All other treatments were found to be ineffective. Based on our laboratory studies, semi-large-scale trials were made with 4N HCl for continuous dehulling of palm kernel in an abrasive peeling machine for the preparation of superiorgrade kernel flour and oil.     

Studies in palm oil crystallization

The melting and crystallization behaviors of palm oil were examined by nuclear magnetic resonance, differential scanning calorimetry, and plasticity measurements and were correlated with composition and chemical characteristics. Fractionation into high melting and low melting components is adversely affected by increase in free fatty acids (FFA), diglyceride content, and degree of oxidation, and hence, for an oil that is to be fractionated, both hydrolysis and oxidation should be kept to a minimum. Palm oil with very low FFA content, obtained from ripe, unbruised fruit, contains substantially more diglycerides than would be expected from the level of FFA present. Liquid and solid palm oil fractions manufactured in the producing countries showed large variation in characteristics, due in part to the use of various fractionation processes. The characteristics used to define the quality of palm oil are also applicable to its fractions.     

Fractionation of palm oil

Because of its fatty acid composition, which includes 50% saturated and 50% unsaturated fatty acids, palm oil can readily be fractionated, i.e. partially crystallized and separated into a high melting fraction or stearin and a low melting fraction or olein. Three main commercial processes for fractionating palm oil are in use: the fast dry process, the slow dry process and the detergent process. All these processes lead to specific products of different quality with different yield and operating costs. The physical and chemical characteristics as well as the triglyceride compositions by high performance liquid chromatography (HPLC) of palm oil fractions from these industrial fractionation processes are given. Other varieties of products produced by specific fractionation are presented with analytical data: the superoleins, palm-mid-fractions and cocoa butter substitutes.     

Ouricury palm kernel oil

A small sample of ouricury palm fruits from Florida, as well as the oil expressed from the kernels imported from Brazil have been investigated. The fruits consisted of 47.5 per cent of pulp and 52.5 per cent of palm nut, of which the kernel amounted to 23.8 per cent. On the basis of the whole fruit, the oil in the pulp only amounted to 0.9 per cent. The kernels from Brazil contained 69.7 per cent of oil, some of the characteristics of which were as follows: Saponification value, 256.9, iodine number (Hanus), 14.69, thiocyanogen value, 12.78, Reichert-Meissl value, 5.93, Polenske number, 18.38, and unsaponifiable matter, 0.27 per cent. The percentages of fatty acids found in the oil were as follows: Caproic 1.66, caprylic 9.10, capric 7.64, lauric 42.7, myristic 8.43, palmitic 7.15, stearic 2.15, arachidic 0.96, oleic 12.18, and linoleic acid 2.04 per cent. Attention has been called to the importance of not assuming the presence in distilled ester fractions of the lower homologues of oleic acid from deductions made only from calculations using the iodine number and saponification value of the fraction without confirmation by other evidence. The present investigation has shown the danger of such assumptions. Carbohydrate Research Division, Bureau of Chemistry and Soils, U. S. Department of Agriculture     

The palm oil situation

In broad perspective, total world demand for oils is growing rapidly, and palm oil will be seen in future years as a welcome addition to total world supply. It also seems clear that palm oil utilization is broadening at a faster rate than production is increasing. It appears this utilization is growing fastest in the “new markets” of Asia, the Mid-East and Latin America, rather than in the “old markets” of Europe and the United States.     

Noncarotenoid hydrocarbons in palm oil and palm fatty acid distillate

Column chromatographic and gas chromatographic-mass spectroscopic (GCMS) analyses for minor and trace noncarotenoid hydrocarbons of crude palm oil and palm fatty acid distillate revealed the presence of a wide range of n-alkanes (C₁₂H₂₆ to C₃₆H₇₄) and n-alkenes in addition to the major component, squalene. Hydrocarbon components concentrated in palm fatty acid distillate where squalene was dominant, but degradation products such as alkenes (from fatty acids or glycerides), aromatic hydrocarbons (from carotenes) and diterpene hydrocarbons (from tocotrienols) were detected in significant quantities, superseding the naturally occurring n-alkanes. Mechanisms proposed suggest that degradation of the valuable vitamin E or tocotrienols needs to be minimized in physical refining.     

The oil palm industry bows to NGO campaigns

Palm oil has become the key supplier to the global edible oils market. Continued oil palm development should be a good thing as it is the most effective supplier in terms of low land usage, and it brings much needed development to poor tropical developing regions. It provides livelihoods for an estimated 4.5 million people. As a monocrop that has supplanted forest and peat lands in areas with unmatched biodiversity and inhabited by poor indigenous tribes, it has been heavily criticized for its negative environmental and social impacts. Escalating NGO campaigns, particularly from Europe, over the last seven years have seriously reined in the speed and prospects for oil palm expansion in Indonesia and Malaysia. Large corporate growers have acceded to NGO pressures, as these have resulted in high‐key boycotts by the likes of Unilever and Nestle. Many large companies have signed on as members of the World Wildlife Fund for Nature‐initiated, Roundtable for Sustainable Palm Oil. Multi‐national consumer brands are being persuaded to change their buying policies, with potential global implications. Strategies to ignore or deny problems in oil palm sustainability have not worked well: a handful of NGOs have played David to the palm oil Goliaths of Indonesia and Malaysia. Since mid‐2010, Indonesia's President is trying to make less‐than‐popular policy changes, and the outcomes bear watching.     

Frying performance of a sunflower/palm oil blend in comparison with pure palm oil

The aim of this study was to test the performance of a vegetable oil blend formulated as alternative to pure palm oil as frying medium. For this purpose, the evolution of many analytical parameters (free acidity, spectrophotometric indices, total polar components, fatty acid composition, short‐chain fatty acids, tocopherol and tocotrienol content and composition, color, flavor evaluated by means of an electronic nose) of the selected blend (sunflower/palm oil 65 : 35 vol/vol) has been monitored during a prolonged frying process (8 h discontinuous frying without oil replenishment) in comparison to pure palm oil. Sensory attributes of the fried food were also evaluated. The blend proved to keep qualitative parameters comparable to those shown by palm oil during the prolonged frying process. Even if some oxidation indices, such as spectrophotometric indices, short‐chain fatty acids and total polar components, increased faster in the blend, it showed a higher tocopherol content and a lower increment in free fatty acids as compared to pure palm oil. Chips fried in the two oils did not show significantly different sensory profiles.     

Comparative evaluation of palm oil color measurement using a prototype palm oil colorimeter

The color of refined palm oil and palm oil products is conventionally measured using the manually operated Lovibond^® Tintometer. In the present study, one manual/visual and three automatic colorimeters for the measurement of vegetable oil color were used for color measurements of refined palm oil. All colorimeters used were commercially available instruments except for an automatic palm oil colorimeter developed specifically for the measurement of palm oil color. The color values obtained from all four instruments were compared using the visually obtained readings as reference values. Results showed that all three automatic instruments gave correlation coefficients of greater than 0.9300 for red color measurements. In addition, the Student t-test showed no difference between the analysis of red color using the visual method and the palm oil colorimeter. This investigation concludes that, although it is extremely difficult to reduce the lack of precision in color measurement of palm oil, a properly designed and calibrated automatic instrument may still be the better choice because reproducibility and repeatability are required in all standard test methods. The palm oil colorimeter offers a ready and relatively inexpensive solution to the problem of color matches based on visual observations.     

Control of crude oil dilution in palm oil mills

This paper discusses the results of development work on the control of crude oil dilution in palm oil mills. The importance of crude oil dilution in palm oil mills is clearly shown by a simple cost-benefit analysis. Preliminary results from a three-phase decanter trial have shown that, besides a clarification system using horizontal or vertical clarifiers, dilution control is also important to a decanter system. A practical approach to the automatic control of crude oil dilution using a flow ratio control system is discussed in depth in this paper. Results obtained from the evaluation of Doppler and magnetic flowmeters have shown that the major obstacle in automatic control of crude oil dilution, i.e., the selection of a suitable flowmeter to measure crude oil flow, has been overcome.     

Palm oil and palm kernel oil in food products

Cocoa butter equivalent (CBE) formulation, especially the compatibility of palm oil based CBE with cocoa butter, is of special interest to chocolate manufacturers. Traditionally palm oil is fractionated to obtain high-melting stearin and olein with a clear point of around 25 C, the latter serving as cooking oil. Recently, palm oil has been fractionated to recover an intermediate fraction known as palm mid-fraction (PMF), which is suitable for CBE formulations. Generally, production of PMF is based on a three-step procedure. However, a dry fractionation system, which includes selective crystallization and removal of liquid olein by means of a hydraulic press, has been developed. Iodine value, solid content (SFI) at different temperatures, cooling curves (Shukoff 0°) and triglyceride/fatty acid composition determination confirmed effectiveness of the procedure followed. A direct relationship between yield, quality of PMF and crystallization temperature during fractionation has been achieved. Yield of 60% for olein of IV 64–67 has been achieved. Yield of 30% for PMF of IV 36–38 and 10% for high melting stearin of IV of 20–22 are also being achieved. High-melting stearin may be used in oleochemical applications, soaps, food emulsifiers and other industrial applications such as lubricating oil. Olein fraction, especially after flash hydrogenation thereby reducing the IV to 62/64, has excellent frying and cooking oil characteristics. Palm olein is also suitable as dietary fat and in infant formulation. Studies on interesterification of high-melting stearin with olein showed possibilities to formulate hardstocks for margarine and spread formulations, even without using hydrogenated fat components. Palm kernel and coconut fats or fractions or derived products are used for confectionery products as partial CB replacers and as ice cream fats and coatings. Coconut oil also serves as a starting material for the production of medium-chain triglycerides.     

Tocopherol content in oil palm leaflet

Mature oil palm leaflets are readily available as byproducts from oil palm plantations.α-Tocopherol and chlorophyll contents of palm leaflets obtained from oil palm trees of different ages and varieties were determined.α-Tocopherol and chlorophyll contents were in the range of 0.14–0.28% and 0.23–0.31%, respectively, in palm leaflets on wet bases. The molar ratios ofα-tocopherol to chlorophyll were 0.78–2.37.     

Utilization of Malaysian palm oil and palm kernel oil for fatty acids and derivatives

Malaysia produces ca. 65% of the world’s palm oil, or (in 1982) ca. 3,500,000 metric tons. By 1985, this will increase to 80% of world production, or ca. 4,800,000 metric tons. Palm oil products are refined, bleached and deodorized oil for edible purposes, palm olein for edible use, palm stearin for edible or industrial use, and the acid oil or fatty acid distillate for industrial uses. The Malaysian processors naturally want to upgrade the products as much as possible.     

Torrefaction of oil palm wastes

This paper describes the effect of torrefaction on the basic characteristics of agricultural biomass wastes in Malaysia, such as empty fruit bunches (EFB), mesocarp fiber and kernel shell as a potential source of solid fuel. Mesocarp fiber and kernel shell exhibited excellent energy yield values higher than 95%. EFB, on the other hand, exhibited a rather poor yield of 56%.