Fatty acids unsaturated fats

Degussa A.G., WO 95/22591, Hydrogenation of Unsaturated Fats, Fatty Acids or Fatty Acid Esters, 1995. 

T Tacke, S Wieland, P Panster, M Bankmaim, R Brand, H Magerlein. Hardening of unsaturated fats, fatty acids or fatty acid esters. U.S. Patent No. 5,734,070, 1998. 

Hardening of Unsaturated Fats, Fatty Acids or Fatty Acid... 

A process is disclosed for continuously hydrogenating unsaturated fats, fatty acids, or fatty acid esters on a shaped catalyst in a solid bed in the presence of an SCF solvent medium. 

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]. 

The rate of oxidation of fats and oils is affected by the oxygen partial pressure, access of oxygen, the degree of unsaturation of fatty acids, the presence of light, heat, antioxidants, and pro-oxidants such as copper, iron, and pigments. The optimal stability of oil was achieved when iron and copper were below 0.1 and 0.02 ppm, respectively (28). 

The fat in beef, mutton, milk, and cheese contains 2-8% trans fatty acids. These naturally occurring trans fatty acids are formed in the rumen of the stomach (of ruminants) by the action of bacterial enzymes. Most of the trans fatty acids of the diet arise from the industrial hydrogenation of food oils. During this process, most of the unsaturated cis fatty acids are converted to saturated fatty acids, but a fraction is converted to trans fatty acids. In relation to all fatty acids present in the indicated food, salad oils contain 8-17% trans fatty acid, shortening contains 14-60%, and margarines 16-70% (Simopoulos, 1996). Overall, about 6% of our dietary fatty acids are trans fatty acids, where most of these are elaidic acid (McKeigue, 1995). 

A soap is a metallic salt of a saturated or an unsaturated higher fatty acid. There may be lead, calcium, magnesium or other metallic soaps, but in practice the only ones which are used as detergents are those containing sodium or potassium. Soap is made on a commercial scale by boiling natural oils or fats with aqueous solutions of sodium or potassium hydroxide, when the following reaction takes place ... 

Nitrosyl chloride is also applied to the determination of C=C groups in fats, fatty acids, and unsaturated hydrocarbons (a review exists).322... 

The liver is the most important organ involved in fatty acid and triglyceride synthesis. It is able to modify body fats by lengthening or shortening and saturating or unsaturating the fatty acid chains. The only fatty acids that cannot be synthesized by the body are those that are polyunsaturated. However, linoleic acid (two double bonds) and linolenic acid (three double bonds) from the diet can be converted to other polyunsaturated fatty acids. This utilization of linoleic and linolenic acids as sources of other polyunsaturated fatty acids is the basis for classifying them as essential fatty acids for humans (Section 8.2). 

Chromosomes are composed of proteins and nucleic acids. 6. Fatty acids in vegetable oils are more unsaturated than fatty acids in animal fats. 

Dietary fats consumed by ruminants first undergo hydrolysis in the rumen and this is followed by progressive hydrogenation of the unsaturated free fatty acids (mainly 18 2 and 18 3 acids) to stearic acid. This helps to explain the apparent anomaly that, whereas their dietary fats are highly unsaturated, the body fats of ruminants are highly saturated. 

The nutritional value of nut and seed products is closely associated with the fatty acid content of the oil. High Unoleic acid content decreases shelf-life. Increasing the oleic/linoleic acid ratio produces a more stable oil with a longer shelf-life. Nutritionally, a high linoleic acid content is desirable, because this acid is an essential fatty acid and produces a hypocholenic effect. Of more than 100 fatty acids, three are essential, linoleic, linolenic and arachidonic. The consensus is that polyunsaturated fat (fatty acids) lowers total blood cholesterol and low-density lipoprotein levels. Lx)w levels of these substances are associated with reduced risk of coronary heart disease and atherogenesis. Mono-unsaturated fatty acids may be beneficial in lower blood cholesterol (Sheppard and Rudolf, 1991). 

Fatty acids consist of a long, nonpolar hydrocarbon tail and a polar carboxylic acid functional group at the head. Fatty acids are the simplest lipid molecules. They have hydrophilic polar heads, but their hydrocarbon chains make them insoluble in water. Fatty acids can also be saturated or unsaturated. Saturated fatty acids have no carbon-carbon double bonds, while unsaturated fatty acids have one or more double bonds in the hydrocarbon chain. The Upid shown below is oleic acid, which is found in animal fat. 

Hydrogenation is utilized to reduce the unsaturation and poly-unsaturation of fatty acids. Hydrogenated fatty acids also can be produced by the hydrogenation of triglycerides followed by splitting of the resulting fat/oil blend. The selective reduction of di- and poly-unsaturation often is accomplished by the use of nickel-based specialized catalysts, by a process often called touch hydrogenation. 

The intermediate m hydrogenation formed by reaction of the unsaturated ester with the hydrogenated surface of the metal catalyst not only can proceed to the saturated fatty acid ester but also can dissociate to the original ester having a cis double bond or to its trans stereoisomer Unlike polyunsaturated vegetable oils which tend to reduce serum cholesterol levels the trans fats produced by partial hydrogenation have cholesterol raising effects similar to those of saturated fats... 

The state of knowledge in the early 1990s of the effects of fat on health lacks clarity and general agreement. There is great support for the thesis that fully saturated fats are associated with problems of atherosclerosis and arterial fatty deposit, but there is evidence that stearates, which are saturates, are only poorly utilized in human digestion. Another body of work has estabUshed a connection between unsaturated fatty acids and a better state of arterial health and lowered fat body attachment to the arterial wall (23) contrary evidence exists that highly unsaturated fats polymerize more readily and thus contribute to arterial plaque formation. 

The unsaturated fatty acids, linoleic [60-33-3] and linolenic [463-40-17, contain two and three double bonds and are considered beneficial components of the diet. The double bond is an essential ingredient for human nutrition when it is in the correct position on the fat molecule. Humans are unable to insert the double bond at the omega-3 and -6 position. Therefore, fatty acids containing double bonds at these positions are essential in the diet, including linoleic and linolenic acids. They are accordingly described as essential fatty acids (EFA) (23). 

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