Palm oil deodorization

Parameter Pretreat Palm Oil (Degummed/Bleached) Refined Bleached and Deodorized Palm Oil... 

Figure 5 shows the Fisher-Tumbull plot for the crystallization of blends of PS in sesame oil (26, 42, 60, and 80%) (9). This model system is a complex crystallization system. PS is a mixture of TAG obtained through fractional crystallization from refined, bleached, and deodorized palm oil (14). Tripalmitin is the TAG with the highest melting temperature in PS (15), and here its concentration was 16.46% w/w ( 0.17%) (9). Our previous research showed that tripalmitin mostly determines the crystallization kinetics of PS and its blends with vegetable oils (i.e.. 

PPO = processed palm oil, stands for different categories of treatment, i.e. neutralized, bleached, deodorized and/or fractionated according to the degree of processing different export duty tariffs may apply N/RPO = neutralized/refined palm oil, BPO = bleached palm oil, CPL = crude palm olein, N/RBPO = neutralized/refined bleached palm oil, N/RPL = neutralized refined palm olein, BPL = bleached palm olein, N/RBDPO = neutralized refined bleached deodorized palm oil, N/RBPL = neutralized refined bleached palm olein, N/RBDPL = neutralized/refined bleached deodorized palm olein. Dp = duty on PPO and Dc = duty on CPO source A. Mohd Nasir. ... 

Ouyang, J. et al. (1980). Formation of carbonyl compounds from beta-carotene during palm oil deodorization. J. Food Sci. 43 1214-1222. 

Tocopherols and tocotrienols are precursors of vitamin E and are important antioxidants in oils. Their reactivity means that they are not stable to many oil processing procedures, including deodorization, which reduces levels by up to 15%. Levels of tocopherols in cocoa butter are usually about 100-300 mg/kg, with the y-isomer (IV) being the major component (about 90%), but they can be entirely absent (Lipp et al., 2001) (Figure 3.3). Tocotrienols have a similar structure with unsaturation of alternate bonds along the alkyl chain. Only y-tocotrienol is found in cocoa butter and this at low levels (< 5 mg/kg). Palm oil is notably high in tocopherols and tocotrienols, of which a-tocopherol and a-tocotrienol make up 20% to 30% each with most of the remainder as y-tocotrienol. 

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. 

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°. 

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). 

Development in Palm Oil Deodorization. The main operation in the deodorizer is the stripping of volatile materials and thermal action due to the combined effects of superheated steam, high temperature, and efficient vacuum. The older deodorizers (prior to 1985) use bubble caps or sieve-tray designs to effect the... 

Refining of Other Palm Products. Beside crude palm oil, crude palm olein, crude palm stearin, cmde kernel oil, crude palm kernel olein, and crude palm kernel stearin can also be refined by either chemical or physical processes described before. The basic unit operations and processing conditions for crude palm olein and stearin are similar to those of palm oil. However, in refining palm kernel products, due to the virtual absence of carotenoids, the earth dosage required in the bleaching stage is lower, usually less than 1.0%. Furthermore, due to the presence of shorter chain (C8-C14) fatty acids, the deodorization temperature required is about 230-250°C. Typical achievable quality of RBD/NBD palm kernel oil is given in Table 34. 

Physical Refining. The by-product in the physical refining of crude palm oil is the pahn fatty acid distillate (PFAD). It is obtained as a condensate of the volatile matters carried over from the deodorizer by the action of the stripping steam. It consists of 80-90% of free fatty acid. It has often been used as a raw material for soap making, feed compounding, and oleochemical feedstock. An important and valuable constituent of PFAD is vitamin E in the form of tocopherols and... 

Palm oil and coconut oil are refined by the physical refining method. The crude oil is bleached with acid-activated clay and citric acid at elevated temperamres under vacuum. The objective is to remove phosphorus (phospholipids), trace metals, oil decomposition products, and some of the color bodies from the crude oil. The volatile impurities in the bleached oil are then removed via steam distillation under very low absolute pressure and high temperature in a deodorizer. 

Figure 19. Palm oil bleaching with natural clay Effect of dosage on bleached and deodorized color (Lovibond red). (This figure is available in full color at http //www.mrw.interscience.wHey. com/biofp.)...

Timms (21) has heat of fusion to 17.7-22.3 kcal/kg for milkfat, 24-31 kcal/kg for fully hardened milkfat, 26-29 kcal/kg for cocoa butter in the p polymorph, 22.6 kcal/kg for refined, bleached, and deodorized (RBD) palm oil, 29.7 kcal/kg for RBD palm kernel oil, 26.0 kcal/kg for RBD coconut oil, 31.6 kcal/kg for fully hardened palm kernel oil, and 31.2 kcal/kg for fully hardened coconut oil. The heat of fusion is an empirical physical property dependent on the thermal history or tempering of the oil. 

Fig. 1. Avrami equation plots for refined, bleached, deodorized (RBD), palm oil (PO) under isothermal.

Refined, bleached, and deodorized palm stearine was obtained from CanAmera Foods (Toronto, Ontario, Canada) lard and canola oil were purchased from a local supermarket. Tween 80 was supplied by Quest International (Lachine, Quebec, Canada). Free fatty acid content was determined [as percentage oleic acid (w/w)] by titration (12). Free fatty acid contents were 0.03, 0.1, and 0.02%, respectively, for the lard, palm stearine, and canola oil. 

Palm fatty acid distillate (PFAD) is a valuable by-product of palm oil processing, from which the production of tocopherols and tocotrienols is technically feasible (Ong and Choo, 1997). PFAD is wildly abundant, as palm oil is the second largest oil produced in the world. It contains 4000-8000 pg/g total vitamin E compounds, which is up to 10 times as much as crude palm oil contains (Tan, 1989 Ong and Choo, 1997). The tocopherol and tocotrienol profiles of PFAD and crude palm oil are similar, consisting of about 85% of tocotrienols, i.e., y-tocotrienol > a-tocotrienol > 8-tocotrienol (Tan, 1989). Because of cholesterol-lowering properties (Lane et al., 1999), the high level of tocotrienols makes PFAD an important source, because most other natural sources are devoid of tocotrienols. Fatty acids and esters, sterols and squalene are removed from PFAD as described above. Finally, the vitamin-E-rich product is purified and deodorized to yield a tocopherol/tocotrienol-rich product of 95-99% purity. 

Kritchevsky, D., Tepper, S. A., Kuksis, A., Wright, S., and Czamecki, S.K. Cholesterol vehicle in experimental atherosclerosis. 22. Refined, bleached, deodorized (RBD) pahn oil, randomized pahn oil and red palm oil. Nutrition Research, 20(6), 887-892. 2000. 

Malaysia Palm Oil Research Institute patented the physical refine method that involves degumming and bleaching, followed by clarification and desodorisation by molecular distillation using lower temperatures (< 170 C) and pressure (100 mTorr), obtaining an oil comparable to the RED (bleached and deodorized) with less than 0.1 % of acidity and impurities, but with vitamin E retention and 80 % of carotenoids, called carotino [28, 29, 33, 34], It is also observed the use of crude palm oil in Bahia (Brazil) and Africa, being part of many culinary dishes [36]. The crude palm oil is reddish because it contains a high amount of y9-caroten (500-1000 mg-kg ) [37]. 

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