Sunflower linoleic acid

Up until now, mostly pure substrates such as methyl oleate and its -isomer, methyl elaidate, have been tested as model substrates for hydroformylation, but in a few cases, linoleates, linolenates, and esters of ricinoleic acid have also been investigated (Figure 6.10). Oleic acid can be derived from new sunflower, linoleic acid from soybean, linolenic acid from linseed, and ricinoleic acid from castor oil. The long-chain mono-unsaturated fatty acid erucic acid (C22) can be extracted from old rapeseed oil. 

Liquid—hquid extraction can be used to obtain high purity linoleic acid from safflower fatty acids or linoleic acid from linseed fatty acids using furfural and hexane as solvents (18). High purity linoleic acid has been obtained from sunflower fatty acids using a dimethylformamide and hexane solvent system (19). 

Even today renewable resources play a dominant role as raw materials for surfactants, but only because of the great contribution made by soaps to the production of surfactants. If the soaps are left out of consideration as native surfactants, petrochemistry holds 65-70% of the production of synthetic surfactants [2]. But for the future a further increase of renewable raw materials is expected in surfactant production [3]. The main reason for this development is the superior digestibility in the environment of products produced from natural materials. The future importance of the renewable raw materials becomes evident from the fact that even now new plants are cultivated or plants are modified to obtain an improved yield. A new type of sunflower has been cultivated to obtain a higher proportion of monounsaturated oleic acid compared with doubly unsaturated linoleic acid [4],... 

As mentioned earlier, both MCTs and LCTs are used in tube feeding products. Corn, soy, and safflower oils have been the mainstay sources of fat in these products, providing mainly co-6 polyunsaturated fatty acids (PUFAs). On the other hand, some newer EN products contain higher quantities of co-3 PUFAs from sources such as fish oil [i.e., docosahexenoic acid (DHA) and eicosapentenoic acid or (EPA)]. Still other formulas contain higher quantities of monounsaturated fatty acids from canola oil and high-oleic safflower or sunflower oils. The essential fatty acid (EFA) content (mainly linoleic acid) of EN... 

Figure 29 shows the separation of triacylglycerols from sunflower seed oil. In the analysis of linoleic acid-rich seed oils, well-shaped peaks are obtained, and excellent resolution of all the main fractions is achieved, with species containing linoleic acid being predominant. 

Loor, J.J., Ueda, K., Ferlay, A., Chilliard, Y., and Doreau, M. 2005. Intestinal flow and digestibility of trans fatty acids and conjugated linoleic acids (CLA) in dairy cows fed a high-concentrate diet supplemented with fish oil, linseed oil, or sunflower oil. Anim. Feed Sci. Tech. 119, 203-225. 

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. 

Oleic acid was increased to 48% of total milk fatty acids by feeding oleamide as a rumen-protected source of oleic acid (Jenkins, 1998). The response was nearly linear up to 5% of supplement in the diet dry matter. Proportions of all de uovo-synthesized milk fatty acids, except butyric, were reduced (Jenkins, 1999). LaCount et al. (1994) abomasally infused fatty acids from canola or high oleic acid sunflower oil into lactating cows. The transfer of oleic acid to milk fat was linear (slope = 0.541 0 350 g infused/ day) the proportion of oleic acid in milk fat increased and proportions of all de novo-synthesized fatty acids, except C4 and C6 decreased. The proportion of Ci8 o also was unchanged. Linoleic acid from canola also was transferred linearly (slope = 0.527 0-90 g infused/day). These transfers from the intestine are nearly identical to that reported by Banks et al. (1976). Hagemeister et al. (1991) reported 42 to 57% transfer of abomasally-infused linolenic acid to milk fat. 

The earliest efforts to modify the composition of milk fat used an insoluble formaldehyde-crosslinked protein to encapsulate unsaturated vegetable oils. In numerous studies using this approach, linoleic acid was increased to as high as 35%, w/w, of the total milk fatty acids (reviewed by McDonald and Scott, 1977). Bitman et al. (1973) fed increasing amounts of safflower oil encapsulated in formaldehyde-treated casein. The content of milk fat increased linearly from 3.5 to 4.6% as supplemental protected oil was increased from 0 to 1320 g/day per cow. The concentration of linoleic acid increased to 33% of total milk fatty acids, with a compensating decrease in Ci6 o and a smaller decrease in Ci4 0. The concentration of milk fat decreased to lower than pretreatment levels when the supplement was removed, a common observation (Pan et al., 1972). A typical milk fatty acid profile from cows fed a protected sunflower/soybean (70/30) supplement is shown in Table 2.1. 

Three fatty acid molecules and one glycerol molecule combine to form the fats that store energy In our bodies and are used to construct the membranes around our cells. This particular fatty acid, linoleic acid, cannot be manufactured in the human body, and is an essential pa> t of a healthy diet found, for example, in sunflower oil. 

Conversely, SFME exhibited relatively poor improvement in oxidative stability with the use of antioxidants, presumably due to the higher concentrations of linoleic acid methyl esters in sunflower oil in comparison to the other biodiesel samples evaluated by the authors. Therefore, a good correlation was found between the improvement in oxidative stability as measured by OSI when antioxidants are used and the fatty acid composition of the biodiesel sample (Mittelbach and Schober, 2003). 

Linoleic Acid occurs as a colorless to pale yellow, oily liquid that is easily oxidized by air. It is an essential fatty acid and the major constituent of many vegetable oils, including cottonseed, soybean, peanut, corn, sunflower seed, safflower, poppy seed, and linseed. Its specific gravity is about 0.901, and its refractive index is about 1.469. It has a boiling point ranging from 225° to 230° and a melting point around -5°. One milliliter dissolves in 10 mL of petroleum ether. It is freely soluble in ether soluble in absolute alcohol and in chloroform and miscible with dimethylformamide, fat solvents, and oils. It is insoluble in water. 

Another class of compounds formed during frying is cyclic monomers of fatty acids. Linoleic acid can react at either the C9 or C12 double bonds to give rings between carbons 5 and 9, 5 and 10, 8 and 12, 12 and 17, and 13 and 17. Cyclic monomers with a cyclopente-nyl ring have been isolated from heated sunflower oil, and their structure is illustrated in Figure 2-26 (Le Quere and Sebedio 1996). 

The following oils are recommended in decreasing order of preference, the bracketed numbers indicating the approximate linoleic acid content sunflower-seed oil (60), poppy-seed oil (60), cotton-seed oil (45). 

These figures are based on the use of sunflower-seed oil containing 5 7 per cent linoleic acid. With other oils, the yield will be proportionally larger or smaller, depending on the analysis of the oil. Approximate values for three oils may be calculated from the values given in Note 3 above. The yield from cotton-seed oil is 26-30 g. The checkers have brominated about nine times the amounts stated in these directions and have obtained proportionate yields. 

Lipids. Representative fatty acid compositions of the unprocessed triglyceride oils found in the four oilseeds are given in Table 4 (see Fats AND FATTYOiLs). Cottonseed, peanut, and sunflower oils are classified as oleic—linoleic acid oils because of the high (>50%) content of these fatty acids. Although the oleic and linoleic acid content of soybean oils is high, it is distinguished from the others by a content of 4—10% of linolenic acid, and hence is called a linolenic acid oil. 

Given the current widespread interest in reducing cancer, obesity, and other maladies, there is considerable interest in the use of the CLAs, either as a mixture or in the form of individual isomers, as beneficial dietary adjuncts. Cow s milk, beef tallow, and products made from them are natural sources of CLA. However, CLA is also readily synthesized in high yield in the laboratory from vegetable oils that are rich in linoleic acid, such as sunflower and safflower. The resulting synthetic product has CLA levels of about 80%, not the 0.3-0.5% (fat basis) found in beef tallow and dairy products (176). As a result, except for studies of the specific effects of foods containing CLA, vegetable oil is the typical source of CLA in contemporary studies and in commercial dietary supplements. This trend will probably continue. 

The Oleic Linoleic Acid Group This is the most common type of vegetable oil and includes peanut or groundnut (38% oleic and 41% linoleic acid), safflower (14% and 75%), sesame (38% and 45%), and sunflower (20% and 69%). The sum of these two acids is generally 80-90% so there can only be low levels of saturated or other acids. At the present time, there is a demand for high oleic oils, so variants of these oils enriched in oleic acid have been developed (Section 4.2.4). Cottonseed (18% and 51%) differs from the others cited here in its higher level of palmitic acid. Low-erucic rape/canola (56% and 26%) and soybean oil (22%... 

Sunflower seed oil is obtained from Helianthus annus grown mainly in the USSR, Argentina, Western and Eastern Europe, China, and the United States. The oil normally contains 60-75% of linoleic acid, >90% of oleic and linoleic acids combined, and virtually no linolenic acid. Its major triacylglycerols are typically LLL (14%), LLO (39%), LLS (14%), LOO (19%), LOS (11%), and other (3%). 

---