Fatty acid in palm oil

Renaud, S.C., Ruf, J.C., and Pethitory, D. (1995) The Positional Distribution of Fatty Acids in Palm Oil and Lard Influences Their Biological Effects in Rats, J. Nutr. 125,229-237. 

Ng, S. (1985) Analysis of positional distribution of fatty acids in palm oil by C-NMR spectroscopy. Lipids, 20, 778-82. 

Two distinctly different types of oils are produced from the fruit of the Southeast Asia and African oil palm, Elaeis guineensis, and its hybrids with the South and Central American palm E. oleifera. Palm oil is otained from the fleshy part of the fruit, which resembles an oversized olive about the size of a small chicken egg. Palm kernel oil is derived from the kernel within the nut. Well over 98 percent of the fatty acids in palm oil belong to the C 16 and C 18 group, whereas approximately 64 percent of the fatty acids in palm kernel oil consist of the C 12 and C 14 lauric group. 

Seven cycles of condensation and reduction produce the 16-carbon saturated palmitoyl group, still bound to ACP. For reasons not well understood, chain elongation by the synthase complex generally stops at this point and free palmitate is released from the ACP by a hydrolytic activity in the complex. Small amounts of longer fatty acids such as stearate (18 0) are also formed. In certain plants (coconut and palm, for example) chain termination occurs earlier up to 90% of the fatty acids in the oils of these plants are between 8 and 14 carbons long. 

The most abundant fatty acids in vegetable oils and fats are palmitic acid (hexa-decanoic acid or 16 0), oleic acid ([9Z]-octadec-9-enoic acid or 18 1 cis-9), and lino-leic acid (cis, cis-9,12-octadccadicnoic acid or 18 2 cis-9 cis-12) [21], Other fatty acids are found in special oils (e.g. 80% 87% ricinoleic acid in castor oil) [23], but these oils are quite rare. Castor oil, for example, has a production rate of 610,000 tons/year compared to the top four palm oil (46 million tons/year), soya oil (40 million tons/year), rapeseed oil (24 million tons/year), and sunflower oil (12 million tons/ year) [24]. Further sources of fatty acids are tall oils (2 million tons/year) [25] and to a lesser degree synthetic fatty acids derived by mainly hydroformylation and hy-drocarboxylation of olefins [23], The summed fatty acid production is estimated to be 8 million tons/year (2006) [23],... 

Oxidation. Oxidation of oils and fats is due to prolonged exposure to air. By virtue of the low polyunsaturated fatty acid content, palm oil is relatively more stable to oxidative deterioration than the polyunsaturated vegetable oils. However, in the presence of trace metals such as iron and copper, excessive oxidation at the olefin bonds of the oleic and linoleic acids can occur, resulting in rancidity. Highly oxidized crude palm oil is known to have poor bleachability and thus requires more bleaching earth and more severe refining conditions, and the final product will likely be of poor stability (44, 45, 68). 

The 10% level of linoleic acid in palm oil seems ideal in meeting the nutritional requirements of this essential fatty acid, without eliciting growth responses in the tumor cells in comparison to more polyunsaturated oils. However, when compared... 

As previously mentioned, the triglycerides found in biomass are esters of the triol, glycerol, and fatty acids (Fig. 3.6). These water-insoluble, oil-soluble esters are common in many biomass species, especially the oilseed crops, but the concentrations are small compared to those of the polysaccharides and lignins. Many saturated fatty acids have been identified as constituents of the lipids. Surprisingly, almost all the fatty acids that have been found in natural lipids are straight-chain acids containing an even number of carbon atoms. Most lipids in biomass are esters of two or three fatty acids, the most common of which are lauric (Cn), myristic (Cu), palmitic (Cia), oleic (Cis), and linoleic (Cis) acids. Palmitic acid is of widest occurrence and is the major constituent (35 to 45%) of the fatty acids of palm oil. Lauric acid is the most abundant fatty acid of palm-kemel oil (52%), coconut oil (48%), and babassu nut oil (46%). The monounsaturated oleic acid and polyunsaturated linoleic acid comprise about 90% of sunflower oil fatty acids. Linoleic acid is the dominant fatty acid in com oil (55%), soybean oil (53%), and safflower oil (75%). Saturated fatty acids of 18 or more carbon atoms are widely distributed, but are usually present in biomass only in trace amounts, except in waxes. 

Large supply of naturally derived lipids can be obtained from plants in which many oils and fatty acids can be readily extracted and purified. Animal sources (e.g., eggs or milkfats) are used to derive complex lipids such as phospholipids and cholesterol. Yield from natural sources is dependent on the weight-percent composition and the efficiency of the extraction procedure. The constitution of fatty acids in vegetable oils varies widely from different sources. For example, oleic acid is present at 64.6% by weight in olive oil but is present at only 0.7% in palm kernel oil. Similarly, castor oil triglyceride is comprised of almost entirely ricinoleic chains. There are numerous raw material suppliers of oils and oil fractions worldwide. As such, the relative cost of bulk purified... 

Wild-type C. necator H16 was used by Kek and co-workers for the production of P(3HB) using two major by-products rich in free fatty acids from palm oil chanical refining processes RAO and PKAO, as the sole carbon source (Kek et al. 2008). A total of 5 g/L of these by-products resulted in approximately... 

Mosley, S.A., Mosley, E.E., Hatch, B., Szasz, J.I., Corato, A., Zacharias, N., Howes, D. and McGuire, M.A. (2007). Effect of varying levels of fatty acids from palm oil on feed intake and milk production in Holstein cows. Journal of Dairy Science, 90,987-993. 

Khosla and Hayes [141] conclusions about cholesterolaemic effects of the saturated fatty acid of palm oil suggest that not all SFAs are cholesterol-raising. According to authors, when fatty acids contents are similar, the palmitic acid appears to have no impact on the plasma cholesterol in normocholesterolaemic subjects. Above 400 mg of dietary cholesterol intakeed per day, PA might be cholesterol increasing, even more than myristic acid and quite neutral underneath this value. Nevertheless, if cholesterol consmnption exceeds the critical value or when hypercholesterolaemic subjects are studied, the PA appears to increase the plasma cholesterol. Furthermore, authors linked the different PA actions to the differences in LDL-receptor status. It seems that more studies are needed to explain these inconclusive results. 

Laurie acid n-dodecanoic acid, CHj-(CH2)u -COOH, one of the most widespread fatty adds, a typical wax fatty add, M, 200.3, m.p. 44 C, b.p.ioo 225°C.L.a. is present esterified in the seed fats of the laurel family (Lauraceae), and makes up 52% of the fatty acids in palm seed oil, 48% in coconut fat,... 

The composition of common fats and oils are found in Table 1. The most predominant feedstocks for the manufacture of fatty acids are tallow and grease, coconut oil, palm oil, palm kernel oil, soybean oil, rapeseed oil, and cottonseed oil. Another large source of fatty acids comes from the distillation of cmde tall oil obtained as a by-product from the Kraft pulping process (see Tall oil Carboxylic acids, fatty acids from tall oil). 

Fats and oils are triesters of the trivalent alcohol glycerol and three (different) even-numbered aliphatic carboxylic acids, the fatty acids. Fats and oils differ in the length and the number of unsaturated bonds in the carbon chain. The shorter Cio-Ci4-fatty acids are obtained from coconut oil and palm kernel oil. These fatty acids are mostly saturated, and they are used in the manufacture of detergents. Cig-fatty acids are more widely used. Oleic acid, a Cig-fatty acid with an unsaturated bond on the ninth carbon atom, can be produced from many crops. Specific varieties or genetically modified plants, such as rape, have a content of over 90% oleic acid [4]. 

The most produced oils and fats are palm and palm kernel oil, soybean oil, and rapeseed oil, and of these, palm and rapeseed oil are mostly used for biodiesel production. The major components of these oils are saturated fatty acids with C8-C18 chain lengths and unsaturated C18 fatty acids, such as oleic acid (one double bond, Fig. 9), linoleic acid (two double bonds) and linolenic acid (three double bonds), which all contain cis double bonds only. In palm oil, the major unsaturated constituent is oleic acid (39%) followed by linoleic acid (11%), while in soybean oil, linoleic acid is the major constituent (54%) followed by oleic acid (22%) and linolenic acid (8%) [70]. 

A remarkable feature of lipids, either vegetal or animal, is that they share the same fatty acids in triglycerides in the range C12-C20 (Table 14.3). However, there are significant differences in composition. Thus, soybean, sunflower and rapeseed oils are all based on C18 acids, the first two being richer in unsaturated linoleic acid, which could introduce a problem of stability with respect to oxidation. The palm oil has an important amount of C16 acid. Coconut oil is given as an example of Cl2-04 rich oil. As in palm oil the composition of tallow spreads over Cl6-08 acids. 

It is important to emphasize that lower homologs of these and other fatty acids are also of biological significance. Specifically, the shorter-chain saturated fatty acids [e.g., butyric acid (4 0) and caproic acid (6 0)], are important constituents of milk lipids, and octanoic acid (8 0) and decanoic acid (10 0) are present in high concentrations in palm oil. The short-chain fatty acids are rarely found in mammalian organs or tissues—with the exception of milk, where they are in relatively high concentration. 

It is generally accepted that the production of biodiesel meeting the E. U. standards is possible from crude oils with a free fatty acid content lower than 2-2.5%, and levels of phospholipids up to 300ppm (Dorado et al., 2004). However the presence of a high amount of phospholipids results in poor biodiesel-glycerol and biodiesel-water separations which in turn results in a lower yield. Due to the lower concentration of P-compounds in palm oil and animal fat, these raw materials can be used without further degumming treatment. 

Most commodity oils contain fatty acids with chain lengths between Cie and C22, with Cig fatty acids dominating in most plant oils. Palm kernel and coconut, sources of medium-chain fatty acids, are referred to as lauric oils. Animal fats have a wider range of chain length, and high erucic varieties of rape are rich in this C22 monoene acid. Potential new oil crops with unusual unsaturation or additional functionahty are under development. Compilations of the fatty acid composition of oils and fats (6, 9, 11, 12) and less-common fatty acids (13) are available. 

Coconut oil belongs to unique group of vegetable oils called lauric oils. The most abundant fatty acid in this group is lauric acid, CH3(CH2)ioCOOH. Other sources of lauric oils are palm kernel, babassu, cohune, and cuphea. 

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