Characteristics of Palm Oil

Palm oil, like all oils and fats, is made up mostly of glyceridic materials with some nonglyceridic materials in small or trace quantities. It is this chemical composition that defines the chemical and physical characteristics of palm oil, which in turn will determine the suitability of the oil in various processes and applications. 

The characteristics of palm oil refinery effluent vary according to the type of refinery operation (chemical or physical refining, fractionation process, etc.), process control, and housekeeping program. It is quite difficult to derive general characteristics for raw effluent. Therefore the choice of treatment system will depend very much on the complexity of the raw effluent, i.e., its flow and characteristics. 

Characteristics of Palm Oil Refinery Effluent. Table 38 shows the characteristics of the effluent from a typical palm oil refinery employing a physical refining process. The effluent is slightly milky and is acidic in nature. It can be seen that the characteristics of the effluent vary quite widely. Nutrient (N and P) contents seem to be sufficient for biological process according to BOD N P of 100 5 1 ratio. It contains low suspended solids and fatty matter, which are mainly dirt and free oil from washwater and oil spillage. 

Siew, W.L. (2000) Characteristics of palm oil from Elaeis guineensis palm oil. MPOB Technology. No. 23, pp. 1-11. 

Palmitic acid (PA) or n-hexadecanoic acid is the most common saturated fatty acid (SFA) found in plants, animals, and microorganisms (Gunstone et al., 2012). As the name suggests, PA is characteristic of palm oil and its saponified form was discovered and isolated for the first time by Fremy (1840). The major difference between palm oil and other vegetable oils is the higher proportion of PA (Table 1). 

Table 7 Characteristics of Palm Oil Products in Dilution with Liquid Oil and Polymorphic Forms After Temperature Cycling Between 4 and 20°C... 

The effect of palm oil fatty acid additive (POEA) on curing characteristics and vulcanizate properties of sdica-filled NR compounds was studied by Ismail [30]. The incorporation of POEA improved the cure rate and state of cure of the compounds. Compared to the control, the incorporation of POEA not only enhanced the vulcanizate properties but also improved the reversion resistance of the silica-filled NR compounds. 

Fig. 34.21. Examples of stearins separated from crude palm oil by chill fractionation. (FromTan, B. K and Flingoh, C. H. OH. "PORIM Survey 1979/80 Oleins and Stearins from Malaysian Palm Oil Chemical and Physical Characteristics," PORIMTechnol. Palm Oil Res. Inst. Malaysia, No. 4, 1981. With permission.)...

Knowledge about the detailed structures of the triglycerides present in palm oil is important because they define some of the physical characteristics of the oil. The melting points of triglycerides are dependent on the structures and position of the component acids present. They also affect the crystallization behavior of the oil. The semisolid nature of palm oil at room temperature has been attributed to the presence of the oleo-disaturated fraction. 

Other characteristics of palm oleins and palm stearin are shown in Table 17. The different types of palm oil products available for export are illustrated in Table 18. 

CHEMICAL AND PHYSICAL PROPERTIES OF PALM OIL 349 TABLE 17. Additional Analytical Characteristics (16). 

Palm stearin, the more saturated fraction of palm oil, is more variable in composition and thus in physical characteristics. The wide range in solid fat content (Table 3.7) is consistent with the wide range in iodine value for the oil. The variation in composition allows food manufacturers a wide choice of materials for their formulations. In fact, many product formulations require some material to provide the solids required at a certain temperature range. Palm stearin can provide the required solids in blends with unsaturated vegetable oils. 

Trans-free vanaspati can be formulated using palm stearin with other oils (Table 3.23) (Nor Aini et al. 1997). Interesterification allows more palm stearin to be incorporated into the formula. Other trans-free formulations are obtained with ternary blends of palm oil/palm stearin/palm olein or palm oil/palm stearin/ palm kernel olein (Table 3.24). These products have characteristics similar to those of hydrogenated vanaspati. Formulations for vanaspati may be varied to suit the requirements of different consumers. Incorporation of more or fewer palm oil products in the formulation generally affects the melting point property, which is a limitation for certain countries. 

Other uses of palm oil are in snack foods, biscuits, ice-creams, salad dressings, mayonnaise, and so on. Fat plays a key role in all the above food items and formulations using palm oil products essentially replace some of the oils used traditionally. Oil suitable for ice-creams should be partly solid at 5°C and at —5°C, substantially liquid at 37°C, and have good melt feel characteristics. Palm oil, with a similar solid fat content profile to butterfat, is one such oil with suitable characteristics for ice-cream formulations. Palmkemel oil is also much used in ice cream products. 

Fat and oil manufacturers relied on tropical fat and oil replacement with soybean, com, cotton, and canola oils that can mimic the characteristics of tropical oils (coconut and palm) and animal fats (lard and tallow). Some fats and oils are considered as healthier than others due to their higher level of polyunsaturated fatty acids relatively to their saturated fatty acids content. For example canola oil shows a healthier profile than soybean oil due to its overall fatty acid composition of 50% less saturated fat and higher monounsaturates. However, the marketing approach of one fat or oil over another stems from the trend toward products offering health claims, such as heart-healthy , may lower cholesterol , etc. 

Jacob, M. Varughese, K.T. Thomas, S., (2006). Dielectric Characteristics of Sisal-Oil Palm Hybrid Biofibre Reinforced Natural Rubber Biocomposites. Journal of Materials Science, Vol. 41, No. 17, (September 2006), ISSN 0022-2461 Jonsher, A.K., (1977). The "Universal" Dielectric Response. Nature, Vo, 267, No.5613, (June 1977), pp. 673-679, ISSN 0028-0836... 

M. Jacob, K.T. Varughese, and S. Thomas, Dielectric characteristics of sisal-oil palm hybrid biofibre reinforced natural rubber biocomposites. J. Mater. Sci. 41, 5538-5547 (2006). 

It is important, however, that the temperature should not be, allowed to rise above 130° F. (54° C.) during the bleaching of palm oil, otherwise the resultant oil on saponification is apt to yield a soap of a foxy colour. The bleached oil retains the characteristic violet odour of the original oil. 

Yousif B. F. and El-Tayeb, N. S. M. (2010). Wet adhesive wear characteristics of untreated oil palm fiber-reinforced polyester and treated oil palm fiber-reinforced polyester composites using the pin-on-disc and block-on-ring techniques. Proceedings of the Institution of Mechanical Engineers, Part J Journal of Engineering Tribology 224(2), 123-131. 

Figure 8.6 Dielectric characteristics of sisal-oil palm hybrid fiber-reinforced natural rubber composites [50]. with permission from Springer Science + Business Media.

In terms of the oil itself, above 470°F (240°C) the triglycerides and the fatty acids in them begin to become reactive. With palm oil, cocoa butter, and some of the more exotic tropical oils such as illipe fat and shea butter, some interesterification may occur, possibly catalyzed by residual soap in the oils or the elevated levels of partial glycerides found naturally in these oils. This interesterification adversely affects the melting characteristics of the oils and their application as cocoa butter replacers and extenders. 

COMPARISON EFFECTS OF PALM OIL FATTY ACID AND STEARIC ACID ON DYNAMIC PROPERTIES, CURING CHARACTERISTICS AND MECHANICAL PROPERTIES OF CARBON BLACK FILLED EPOXIDIZED NATURAL RUBBER COMPOUNDS Ismail H Kamal S K Mark S E Universiti Sains Malaysia... 

The effects of palm oil fatty acid and stearic acid on dynamic properties, curing characteristics and mechanical properties of carbon black-filled epoxidised NR compounds were studied. It was found that the scorch time and cure time increased with increasing... 

The potential of palm oil fatty acid as an activator in NR gum compounds is studied. The curing characteristics and mechanical properties of NR gum compounds with palm oil fatty acid as an activator are... 

Fats and fatty oils). For the most part, oil is contained in the kernel or embryo of the seed, though it can also occur in the flesh of the ginkgo fmit and in the endosperm of coconut, palm, and pine nuts. Relative amounts of some fatty acids present in a few types of nuts are given in Table 5. Considerable variations in the percentages of fatty acids have also been reported in both pecan and peanut oils from a variety of sources. (Table 6). (For main physical characteristics and the composition of nut oils, see Fats and fatty oils. 

Current production of NR is about 5.2 X 10 tonnes. For some years it has enjoyed a premium price over SBR because of its desirable characteristics described above and, compared with other large tonnage polymers, a somewhat restricted supply. Clearly it is difficult to substantially increase the production of such a material in a short period of time and indeed the attractions of other crops such as palm oil as well as the desire to move away from a monoculture economy mitigate against this. The indications are that, unless there is undue intervention of political factors, the future of natural rubber as a major elastomer remains secure. 

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