Refining palm oil

Crude and refined palm oils, refined palm kernel oil, and refined palm stearin of iodine value (IV) 35 and 41 are commercial samples obtained from various refineries around the Klang Valley region and used without any treatment. 

Crude/palm oil Refined (RBD) palm oil Refined palm kernel oil ... 

Besides the by-products from palm oil refining processes, the feasibility of using POME as the feedstock in PHA production had also been studied. Anaerobically, treated POME was used as carbon source for PHA production by Rhodobacter sphaeroides IPO 12203 and Comamonas sp. EB172 (Hassan et al. 1996, 1997b Zakaria et al. 2010a). The organic acids produced from anaerobic treatment of POME, particularly acetic and propionic acids, were successfully converted into PHA with polymer contents ranging from 59 to 67 wt% of CDW. 

Palm Oil Refiners Association of Malaysia, PORAM. Standard Specifications for Crude Palm Oil [online]. 2014 [2014 Feb 17]. Available from URL http //www.poram.org.my/database/contract/specifications.htm. 

In addition to hydrolysed triglycerides, palm fatty acid distillates also contains a significant amount of palmitic acid. Palm fatty acid distillates is a byproduct of the palm oil refining process and contains predominantly FFA (palmitic, oleic and linoleic, and possibly some stearic acid) [71]. This byproduct, as well as similar byproducts from other crude oil refining processes, are thus also potential sources of palmitic acid. 

Palm Oil Refiners Association of Malaysia representing the interest of refiners in the oil palm industry. 

Oils from livers of cod and other fish species were early sources of vitamin D3 also, ergosterol was irradiated by ultraviolet light to produce vitamin D2. Currently, most of the commercial vitamin D also is produced synthetically. Vitamin E has been obtained commercially from extracted wheat germ oil, and recovered from deodorizer condensates from oil refining plants. Palm oil refining residues also are indicated major sources in the future. 

For the purposes of making polyols from these triglycerides, oils which contain a high level of unsaturation are desirable. Oils such as soy, canola, and sunflower are acceptable due to relatively low levels of saturated fatty acids, while feedstocks such as palm oil are considered unusable without further purification or refinement due to high levels of saturated fatty acids. Table 1 outlines the composition of several oils (3). 

Non-refined oils are easier to detect and authenticate than organic oils, though the absence of a small percentage of some refined oil in the product would be difficult to prove. Where unrefined palm oil was adulterated with rapeseed has already been described above. Where an oil is authentic as to its source, but possibly at least partially refined, in order to check its authenticity, it would then be necessary to build up a database of the expected ranges of values for refined and non-refined oils. Chemical and physical techniques that should be checked are ... 

In the following study the conversion of non-refined palm oil, waste cooking oil, animal fats, deodorizer distillate, and soap stocks into biodiesel will be reported. Finally, the direct use of animal fat for the production of electricity will be discussed. 

A flow sheet for a semi-continuous interesterification line with postbleaching ability is shown in Fig. 34.27. The oil must be degummed, well-refined (<0.05 percent FFA), and free from peroxides and moisture that causes production of soaps. Palm oil stearin and completely saturated (<5 IV) Cl 8 hydrogenated fats generally are trans free and may be used as part of the feed. Reactions are run under vacuum, and oil is best stored under nitrogen between processes.44... 

Palm Oil (Unhydrogenated) is a deep orange-red fat obtained from the pulp of the fruit of the oil palm Elaeis guineensis Jacq. (Fam. Aracaceae) usually by boiling, centrifugation, and mechanical expression. It is refined, bleached, and deodorized to substantially remove free fatty acids, phospholipids, color, odor and flavor components, and miscellaneous other non-oil materials. It is a semisolid at 21° to 27°. 

One of the highest known concentrations of carotenoids occurs in crude palm oil. It contains about 15 to 300 times more retinol equivalent than carrots, green leafy vegetables, and tomatoes. All of the carotenoids in crude palm oil are destroyed by the normal processing and refining operations. Recently, improved gentler processes have been developed that result in a red palm oil that retains most of the carotenoids. The composition of the carotenes in crude palm oil with a total carotene concentration of 673 mg/kg is shown in Table 6-5. 

Cmde oils generally contain phospholipids that are removed during the degum-ming stage of refining as a crude mixture (lecithin). This valuable product is the basis of the phospholipid industry, and phospholipids are used extensively in food products, in animal feeds, and in industrial processes. The major members are phosphatidylcholines, phosphatidylethanolamines, and phosphatidylinositols and are accompanied by smaller proportions of other phospholipids. Soybean oil (3.2%), rapeseed oil (2.5%), and sunflower seed oil (1.5%) contain the proportions of total phospholipids indicated in parentheses and are the main sources of commercial lecithins, especially soya lecithin. Palm oil contains little or no phospholipids (7-9). 

Crude palm oil used to be the main form of export in the past. With the establishment of refineries especially in Malaysia during the mid-1970s and 1980s, refined palm oil products have replaced the crude as the main form of palm oil export. A wide range of processed or semiprocessed products are exported, and these include the different fractions of processed pahn oil known as palm olein (liquid) and palm stearin (solid). The availability of refineries also led to the production of specialty fats products aimed at the confectionery markets. A similar trend has been seen in the export of pahn kernel oil. Palm kernel oil is a coproduct to palm oil produced at a ratio of 10-13 tons of palm kernel oil for every 100 tons of palm oil. Even the export of refined palm kernel oil has begun to decline as more is being used locally by the oleochemical industry that has been estabhshed in recent years. 

The major importers of palm oil used to be the developed countries of the European Economic Community (EEC), the United States, and Japan. They accounted for about 75% of the imports of palm oil in the early 1970s. With the increasing exports of refined palm oil products, many developing countries, which did not have refining capacities, were able to import processed palm oil for direct consumption with minimal or no further refining. This helped to expand the market for palm... 

As mentioned previously, partial glycerides are artifacts of the extraction process, especially the stages prior to sterilization. Oil obtained from unbruised sterilized fruits shows trace levels of partial glycerides. Random analyses of samples of refined palm oil, pahn olein, and palm stearin have shown the presence of about 2% of 1,2-diglycerides and about 4% of 1,3-diglycerides with trace amounts of monoglycerides. These partial glycerides are important as they are known to affect the crystallization behavior of the oil. 

Cmde palm oil contains tocopherols and tocotrienols in the range of 600-1000 ppm. Refined palm oil retains about 50% of these products. Tocopherols and tocotrienols are antioxidants and provide some natural oxidative protection to the oil. Table 8 shows the types of tocopherols and tocotrienols present in palm oil. 

TABLE 10. Sterol Composition of Crude and Refined Palm Oil and Their Products (ppm) (11). ... 

Production cost of crude palm oil is made up of cost of production of fresh fruit bunches (EFB) and the cost to mill the FFB. Refining costs are incurred when crude palm oil undergoes refining to produce processed palm products. 

Refining Cost. Crude palm oil can be further processed by refining. Presently, most of the palm products obtained in the market are processed using physical or steam refining. Crude or processed palm products may also undergo fractionation where the solid and the liquid portions are separated. The total cost of refining a ton of palm oil is about 25.92 while the cost of fractionation is about 5.55 per ton. 

Two methods, namely physical rehning and chemical rehning, are available for refining crude palm oil. They differ basically in the manner in which the free fatty acids are removed. Physical rehning has become the major processing route because of its cost effectiveness, efficiency, and simple effiuent treatment (39). Both processes are able to produce rehned, bleached, and deodorized (RBD) palm oil of desirable quality and stability suitable for edible purposes (40). The unit operations involved in these two processes and the components removed are shown in Figure 12 and Table 31, respectively. 

Physical Refining. Physical rehning was introduced to palm oil processing in 1973 (41). Its unique feature is that the deacidihcation, deodorization, and thermal decomposition of carotenoids are accomplished in one process in a stainless steel deodorizer. It is a continuous processing consisting of a two-step operahon of pretreatment followed by steam distillation (42). 

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