Palmitic acid oils

Palmitic Acid Oils The commodity oil richest in palmitic acid is pahn oil (44%). This oil is also rich in oleic acid (37%), contains lower levels of linoleic acid (10%), and is a valuable source of minor components, especially carotenes, toco-pherols, and tocotrienols (Section 3). Palm oil is an important world commodity in feeding the developing world. It is fractionated extensively to give a wider range of uses as palm olein and palm stearin. The only other commodity oil with a significant level of palmitic acid is cottonseed oil (27%). 

One way to modify soybean oil FA composition is to increase (in comparison with the traditional oil) the concentration of both stearic and palmitic acids. Oils... 

Distillation By-Products. Of the CTO distiHation by-products, ie, pitch, heads, and DistiHed TaH Oil (DTO), only the last, a unique mixture of rosin and fatty acids, has significant commercial value. Pitch and heads are used as fuel the former has a fuel value of 41,800 kj/kg. TaH oil heads have outstanding solvent properties, but also have a bad odor, which is hard to remove. They contain a relatively high fraction of palmitic acid which can be recovered by crystallization. 

A series of sorbitol-based nonionic surfactants are used ia foods as water-ia-oil emulsifiers and defoamers. They are produced by reaction of fatty acids with sorbitol. During reaction, cycHc dehydration as well as esterification (primary hydroxyl group) occurs so that the hydrophilic portion is not only sorbitol but also its mono- and dianhydride. The product known as sorbitan monostearate [1338-41 -6] for example, is a mixture of partial stearic and palmitic acid esters (sorbitan monopalmitate [26266-57-9]) of sorbitol, 1,5-anhydro-D-glucitol [154-58-8] 1,4-sorbitan [27299-12-3] and isosorbide [652-67-5]. Sorbitan esters, such as the foregoing and also sorbitan monolaurate [1338-39-2] and sorbitan monooleate [1338-43-8], can be further modified by reaction with ethylene oxide to produce ethoxylated sorbitan esters, also nonionic detergents FDA approved for food use. 

Z,Z,Z,)-9,12,15-octadecatrienoic acid). Fish oils contain esters of eicosanoic and docosanoic acids with four to six double bonds separated by single methylene groups, eg, (i7//-Z)-4,7,10,13,16,19-docosahexaenoic acid [6217-54-5] in menhaden oil (4). The fatty acid with conjugated double bonds in tung oil is a-eleostearic acid [506-23-0] ((F,Z,F)-9,ll,13-octadecatrienoic acid) the predominant fatty acid in oiticica oil is licanic acid [17699-20-6] (4-oxo-(F,Z,F)-9,ll,13-octadecatrienoic acid). In all oils, other fatty acids including palmitic acid [57-10-3] (hexadecanoic acid), stearic acid [57-11-4] (octadecanoic acid), and oleic acid [112-80-1] ((Z)-9-octadecenoic acid) also are present. 

Palmitic Acid.—This acid, together with steanc and oleic-acids, in the form of the glycerides, are the chief constituents of fats. Palmitin (glyceride of palmitic acid) is also found in certain x egetable oils like palm and olive oil. The acid occurs also as the cetyl ester in spermaceti and as the myricyl ester in bees-wax. It may be obtained from oleic acid by fusion with potash,... 

Although vegetable oils usually contain a higher proportion of nnsatnrated fatty acids than do animal oils and fats, several plant oils are actually high in saturated fats. Palm oil is low in polyunsaturated fatty acids and particularly high in (saturated) palmitic acid (whence the name palmitic). Coconut oil is particularly high in lanric and myristic acids (both saturated) and contains very few nnsatnrated fatty acids. 

The Oil coutainS d-c-pinene, d-limonene, Intcea o[ palmitic acid, salicylic aHd, aud a pberiol, small quaotitles of esters of formic and valerianic acids, and a sesqnUerpene of specific gravitv 0 910, and retractive index 1-oOSO. 

To make ascorbic acid soluble in fats, it is reacted with fatty acids, such as palmitic acid, to form ascorbyl palmitate. This is used to prevent oxidation in fats and oils. 

A soap-based powder can be produced in combination with ester sulfonates. Thirty-five percent of a sodium soap mixture (5% lauric acid, 5% myristic acid, 52% palmitic acid, 21% stearic acid, 12% oleic acid, and 5% linoleic acid) is mixed with 15% sodium a-sulfo palm oil fatty acid methyl ester, 3% lauric acid ethoxylate, 5% sodium silicate, 17% sodium carbonate, 20% Na2S04- 10H2O, and 5% water [79]. 

The term fat is applied to solid esters of fatty acids with glycerol (glycerides) if the fat is liquid at the ordinary temperature, it is conventionally called a fatty oil, vegetable oil or animal oil. The acids which occur most abundantly are palmitic acid CH3(CH,),4COOH, stearic acid CH,(CH,),4C00H and oleic acid CH,(CH,),CH=CH(CH,),COOH. Upon hydrolysis, fats yield glycerol and the alkali salts of these acids (soaps) ... 

Plastic foils used for wrapping TLC plates were once reported to contain amides of oleic, stearic, or palmitic acid as antiblocking agents which may migrate from the wrapping material [28]. Similarly, Amos [447] has encountered interferences from contaminants in solvents in the TLC analysis of phenolic AOs in turbine oils. 

Oil Palmitic acid Stearic acid Oleic acid Linoleic acid Linolenic Elaeostearic Ricinoleic Gondoic Erucic acid... 

Animal and dairy fats can be differentiated from plant lipids on the basis of the FA distribution animal fats generally contain less palmitic acid than stearic acid, while palmitic acid predominates over stearic acid in plant oils. 

The ratio between the amounts of azelaic and palmitic acids (A/P) is a parameter for differentiating drying oils from egg lipids in paint samples because the amount of dicarboxylic acid formed in the ageing of egg lipids is considerably less than it is in drying oils. Values of A/P >1 indicate a drying oil, values of A/P <0.3 are typical of egg lipids,... 

The ratio of palmitic acid to stearic acid (P/S) can be used to differentiate between drying oils, since these two saturated monocarboxylic acids are less subject to chemical reactions during treatment and ageing. Also, they have a similar chemical reactivity, so their ratio can be hypothesized to be relatively unaltered during ageing. The P/S ratio approach was pioneered by Mills [10], and has been subsequently adopted in a number of studies [7 9]. Typical values of the P/S ratio are 1 2 for linseed oil, 2 3 for walnut oil, 3 8 for poppy seed oil and 2.5 3.5 for egg. 

Figure 11.2 Py/silylation GC/MS chromatograms of aged linseed oil pyrolysed in the pre sence of HMDS, (a) Pyrogram obtained with a microfurnace pyrolyser pyrolysis temperature 600 °C furnace pressure 14 psi purge flow 0.5 ml min (b) Pyrogram obtained with a resistively heated filament pyrolyser pyrolyser interface I80°C transfer line 300°C valve oven 290°C. 1, Hexenoic acid, trimethylsilyl ester 2, hexanoic acid, trimethylsilyl ester 3, heptenoic acid, trimethylsilyl ester 4, heptanoic acid, trimethylsilyl ester 5, octenoic acid, trimethylsilyl ester 6, octanoic acid, trimethylsilyl ester 7, nonenoic acid, trimethylsilyl ester 8, nonanoic acid, trimethylsilyl ester 9, decanoic acid, trimethylsilyl ester 10, lauric acid, trimethylsilyl ester 11, suberic acid, trimethylsilyl diester 12, azelaic acid, trimethylsilyl diester 13, myristic acid, trimethylsilyl ester 14, sebacic acid, trimethylsilyl diester 15, palmitic acid, trimethylsilyl ester 16, stearic acid, trimethylsilyl ester...

In the characterization of alkyd resin formulations the palmitic acid to stearic acid (P/S) ratio, often used to identify the type of oil in a binder, cannot be applied as many different oils other than the traditional ones are commonly employed in industrial formulations. Moreover, they are often in mixtures, with the additional complication that fatty acids are also sometime added to the vegetable oils, thus making it impossible to rely on measured P/S values. In any case it is important to always derivatize the samples if Py-GC/MS is used and an alkyd is suspected. Phthalic anhydride will be detected also in an underivatized alkyd pyrogram however, isophthalic acid will not, leading to confusion and the possibility of uncorrected identification [92]. 

In positive ion mode, the characteristic peaks representative of the binding media were fatty acids from lead soaps (of palmitic acid at m/z 461 463 and of stearic acid at m/z 489 491). Other peaks corresponding to mono- and diacylglycerol cations, protonated stearic acid or its acylium ions could be found in the spectra of the reference products but not in the paint sample. The spectrum of lead white egg tempera paint exhibits peaks of phosphocholine (m/z 184) and protonated ketocholesterol (m/z 401). These peaks were not found in the spectrum from the cross-section. In negative ion mode, the spectrum of the oil... 

To identify the kind of oil, Keune et al. [2005] used the classical approach based on the palmitic acid/stearic acid (P/S) ratio usually obtained from GC/MS data. Ratios less than 2 correspond to linseed oil, whereas ratios higher than 5 correspond to poppy seed oil. Intermediate values can be attributed to walnut, poppy seed oil or mixtures [Schilliing and Khaijan 1996]. Keune et al. first show that ionization efficiency is the same for the two fatty acids in negative ion mode permitting the use of ToF-SIMS for the calculation of the P/S ratio. A test on the oil-paint model system shows a ratio of 2.0 for linseed oil and 3.6 for poppy seed oil, which can allow the two oils to be differentiated. Nevertheless, it is important to note that the ratio is not constant all over the cross-section. 

Palma istle, 11 296 Palm fibers, processing of, 11 298 Palmitic acid, 22 756 boiling point, 5 53t percentage in selected fats and oils, 2 519t 5 47t... 

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