Animal fats fatty acid source

Figure 2-5 Chromatogram of Milk Fat Fatty Acid Composition Analyzed as Butyl Esters on a 30-m Capillary Column. Source Reprinted from R.G. Ackman, Animal and Marine Lipids, in Improved and Technological Advances in Alternative Sources of Lipids, B. Kamel and Y. Kakuda, eds., p. 298, 1994, Aspen Publishers, Inc.

Table 10.3 Fatty acids of some animal fats from UK sources ...

Soap Soap has been known since antiquity as a surfactant for removal of soil from textiles. Soap is readily made by basic hydrolysis (saponification) of animal fats (fatty esters of glycerol). Soap is the resultant sodium sal t of the fatty acids, with the composition depending on the source of fatty acid esters. Soap suffers from one major deficiency as a surfactant in hard water containing calcium and magnesium cations, the sodium ion in soap is replaced by these multivalent ions to form insoluble salts which caimot act effectively as surfactants. 

Fatty acids derived from animal and vegetable sources generally contain an even number of carbon atoms siace they are biochemically derived by condensation of two carbon units through acetyl or malonyl coenzyme A. However, odd-numbered and branched fatty acid chains are observed ia small concentrations ia natural triglycerides, particularly mminant animal fats through propionyl and methylmalonyl coenzyme respectively. The glycerol backbone is derived by biospeciftc reduction of dihydroxyacetone. 

Fats and oils may be synthesized in enantiomerically pure forms in the laboratory (30) or derived from vegetable sources (mainly from nuts, beans, and seeds), animal depot fats, fish, or marine mammals. Oils obtained from other sources differ markedly in their fatty acid distribution. Table 2 shows compositions for a wide variety of oils. One variation in composition is the chain length of the fatty acid. Butterfat, for example, has a fairly high concentration of short- and medium-chain saturated fatty acids. Oils derived from cuphea are also a rich source of capric acid which is considered to be medium in chain length (32). Palm kernel and coconut oils are known as lauric oils because of their high content of C-12 saturated fatty acid (lauric acid). Rapeseed oil, on the other hand, has a fairly high concentration of long-chain (C-20 and C-22) fatty acids. 

Fa.ts nd Oils. Eats and oils from rendering animal and fish offal and vegetable oilseeds provide nutritional by-products used as a source of energy, unsaturated fatty acids, and palatabiHty enhancement. Eats influence the texture in finished pet foods. The use and price of the various melting point fats is deterrnined by the type and appearance of the desired finished food appearance. 

Xanthates and dithiophosphates dominate sulfide flotation usage, though several other collectors including more recently developed ones are gaining acceptance rapidly (43). As of this writing, this is an active area of research. Many of the sulfide collectors were first used ia the mbber iadustry as vulcanizers (16). Fatty acids, amines, and sulfonates dominate the nonsulfide flotation usage. The fatty acids are by-products from natural plant or animal fat sources (see Fats and fatty oils). Similarly petroleum sulfonates are by-products of the wood (qv) pulp (qv) iadustry, and amines are generally fatty amines derived from fatty acids. 

The quaHty, ie, level of impurities, of the fats and oils used in the manufacture of soap is important in the production of commercial products. Fats and oils are isolated from various animal and vegetable sources and contain different intrinsic impurities. These impurities may include hydrolysis products of the triglyceride, eg, fatty acid and mono/diglycerides proteinaceous materials and particulate dirt, eg, bone meal and various vitamins, pigments, phosphatides, and sterols, ie, cholesterol and tocopherol as weU as less descript odor and color bodies. These impurities affect the physical properties such as odor and color of the fats and oils and can cause additional degradation of the fats and oils upon storage. For commercial soaps, it is desirable to keep these impurities at the absolute minimum for both storage stabiHty and finished product quaHty considerations. 

Although vegetable oils and animals fats were commonly used in ancient times, most higher acids were not known until the beginning of the nineteenth century. Then the nature of the naturally occurring 18-carbon fatty acids was estabHshed, and hundreds of long-chain fatty acids have been isolated from natural sources and characterized. 

The main difference between oils and fats is that oils are liquid at room temperature and fats are solid at room temperature. Oils, such as olive oil or corn oil, usually come from plant sources and contain mainly unsaturated fatty acids. Fats, such as butter and lard, contain an abundance of saturated fatty acids and generally come from animal sources. 

To summarise, a fractionation step allows the isolation of the compounds of interest from the other molecular constituents, particularly from the fatty acids that are well-ionised. To compensate for the low ionisation yield of some compounds, such as TAGs, the solutions may be doped with a cation. Samples are then directly infused into the ion electrospray source of the mass spectrometer. A first spectrum provides an overview of the main molecular compounds present in the solution based on the peaks related to molecular cations. The MS/MS experiment is then performed to elucidate the structure of each high molecular compound. Table 4.2 shows the different methods of sample preparation and analysis of nonvolatile compounds as esters and TAGs from reference beeswax, animal fats and archaeological samples. 

Technique selection Carbon-13 ratios of the extracted fatty acids may provide further information on the source of the animal fat. 

Oleic acid is a normal constituent of animal fat, including ant fat. When an ant dies and its body begins to decompose, its fat breaks down and releases odoriferous fatty acids. If the ant dies within its nest, the odor of oleic acid serves as a posthumous chemical signal to its surviving nestmates. On detecting oleic acid, an ant worker s response is to pick up the source (the dead ant) and carry it a short distance toward the nest entrance before setting it down. Eventually, after several workers have moved it, the carcass reaches the entrance, where it is finally ejected from the nest. 

Fuel. Lipids are an important source of energy in the diet. In quantitative terms, they represent the principal energy reserve in animals. Neutral fats in particular are stored in specialized cells, known as adipocytes. Fatty acids are released from these again as needed, and these are then oxidized in the mitochondria to form water and carbon dioxide, with oxygen being consumed. This process also gives rise to reduced coenzymes, which are used for ATP production in the respiratory chain (see p. 140). 

Butyric acid is a carboxylic acid also classified as a fatty acid. It exists in two isomeric forms as shown previously, but this entry focuses on n-butyric acid or butanoic acid. It is a colorless, viscous, rancid-smelling liquid that is present as esters in animal fats and plant oils. Butyric acid exists as a glyceride in butter, with a concentration of about 4% dairy and egg products are a primary source of butyric acid. When butter or other food products go rancid, free butyric acid is liberated by hydrolysis, producing the rancid smell. It also occurs in animal fat and plant oils. Butyric acid gets its name from the Latin butyrum, or butter. It was discovered by Adolf Lieben (1836—1914) and Antonio Rossi in 1869. 

Butyric acid is one of the simplest fatty acids. Fatty acids, which are the building units of fats and oils, are natural compounds of carbon chains with a carboxyl group (-COOH) at one end. Most natural fatty acids have an unbranched carbon chain and contain an even number of carbon atoms because during biosynthesis they are built in two carbon units from acetyl coenzyme A (CoA). Butyric acid is an unsaturated fatty acid, which means all carbon-carbon bonds are single bonds. Common names for fatty acids stem from their natural sources. In addition to butyric acid, some other common saturated fatty acids include lauric acid, palmitic acid, and stearic acid. Lauric acid was first discovered in Lauraceae (Laurus nobilis) seeds, palmitic oil was prepared from palm oil, and stearic acid was discovered in animal fat and gets its name from the Greek word stear for tallow. 

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