Vegetable oils and animal fats

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. 

Table 1. Common fatty acids in vegetable oil and animal fat triglycerides [2,3]...

In biodiesel preparation, vegetable oils and animal fats are typically employed as biomass feedstocks, but waste greases such as yellow grease and brown grease can also be used. Thus, biodiesel synthesis provides a means for... 

Figure 1 Chemical structures of vegetable oils and animal fats (Ri, R2, R3 = alkyl groups )...

Chromarod FID peaks of sterols, diglycerides, monoglycerides, and polar lipids are narrower and sharper than peaks of triglycerides and free fatty acids when analyzed using either method described in this unit (see Basic Protocol and Alternate Protocol). Hydrogenation of total lipids (see Support Protocol) results in much sharper and narrower peaks, which in turn substantially improves the resolution between lipid classes. The accuracy and precision in quantitating lipid classes of vegetable oils and animal fats are expected to be better than those from marine lipids. 

Volatile acid number (Reichert) — 25-30, exceptionally 33. That for cacao butter = 7-9, and that for vegetable oils and animal fats about 1 or rather more. 

A case-control study (Ascherio et al., 1994), a cross-sectional study (Bolton-Smith et al., 1996) and three prospective studies the Nurses Health Study (Willett et al., 1993), the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study (Pietinen et al., 1997), and the Zutphen Elderly Study (Oomen et al., 2001), separately assessed the effect of TFAs from hydrogenated vegetable oil and animal fat on the risk of CHD. With the exception of the small Zutpen Elderly Study (Oomen et al., 2001), the studies found that the positive association with the risk of CHD was explained entirely by the intake of TFAs from hydrogenated vegetable oil. 

Some of the renewable resources for the production of green energy are vegetable oils and animal fats. The use of neat lipids as transportation fuel has not been very successful due to their high viscosity which is leading to engine problems. The production of biodiesel (alkyl esters of fatty acids) is one of the best alternatives, and the blending of biodiesel with petroleum diesel is now widespread in Europe and in the U.S. 

NExBTI A process for making diesel fuel from vegetable oils and animal fats. Developed by Neste Oil and awarded the 2006 Finnish Chemical Industry Innovation Award. Expected to commercialized in Porvoo, Finland, in 2007. 

Although petroleum products had been used earlier, their use only became important from the middle of the nineteenth century. They then slowly revolutionised lubrication because of their effectiveness, stability, availability and cheapness, and because of the wide range of viscosity grades which could be easily produced. Vegetable oils and animal fats continued to be used as alternatives, especially where there was a need for high load-carrying capacity or low friction, but otherwise little effort was made to find other types of lubricant for many years. 

Trace metals are present in crude vegetable oils at parts per million (ppm) levels. Researchers have shown that soybean oil flavor can deteriorate from autoxidation, even at an iron content as low as 0.3 ppm (26) in the deodorized oil. Metal initiators initiate autoxidation in all vegetable oils and animal fats. 

Sterols Sterols are quantitatively the most important components of the unsaponifiable fraction of vegetable oils and animal fats (Figure 7). 

Society for Testing and Materials (ASTM) are shown in Table 10.2. After fine-tuning and approval, the ASTM standards are expected to eliminate many of the potential problems that can result from the large number of vegetable oils and animal fats that can be used to produce biodiesel. In other words, when a particular manufacturing source supplies biodiesel that meets the ASTM standards, it is assumed it will be fully compatible with all other sources of biodiesel and exhibit the same end-use characteristics even though the feedstock may not be the same at each manufacturing site. 

A variety of unsaturated FAs occur naturally in large quantities. These acids contain an even number of carbon atoms 18-carbon atoms containing one, two, and three double bonds occur most frequently. The most abundant monoenic acid in vegetable oils and animal fats is oleic acid (C18 1). Rich sources of C181 are olive oil (70%), peanut oil (40%), sesame oil (40%), rice bran oil (45%), Camellia oleifera tea seed oil (80%), beef tallow (40%), and lard (45%). 

Most vegetable oils (and animal fats and oils) have the triglyceride structure. Fig. 6.8, as tri-esters derived from glycerol and fatty, carboxylic, acids. The fatty acids are almost always straight chains containing between 8 and 22 carbon atoms and may be saturated, mono- or polyunsaturated. Vegetable oil compositions are normally described in terms of their fatty acid content, referring to the acid ester moieties actual fatty acids present in the oil are known as free fatty acids. 

Biodiesel (fatty acid methyl esters) is an alternative and renewable energy source, the development of which is hoped to reduce global dependence on petroleum, as well as air pollution. Biodiesel generated Ifom a variety of vegetable oils and animal fats has characteristics similar to those associated with petro-diesel, including viscosity, volumetric heating value, cetane number, and flash point [1-3]. Several processes have thus far been developed for the production of biodiesel via acid-, alkali-, and enzyme-catalyzed... 

Soap Real soap is made from natural products such as vegetable oils and animal fats. It is an effective cleaning agent that biodegrades quickly and has a minimal impact on the environment. Second best is an environmentally friendly dishwashing liquid. 

A new development in the area of alternative diesel fuels is a fuel produced from vegetable oils and animal fats using specially modified hydrogenation processes in a conventional petroleum processing facility (Rantanen et al., 2005). This fuel retains the low sulfur and low aromatic character of biodiesel but contains no oxygen and has a heating value that is similar to petroleum diesel fuel. Recent U.S. interest in this approach has expanded due to governmental announcements that the fuel qualifies for federal excise tax credits. 

With triacylglycerols being the major components of vegetable oils and animal fats, the properties of biodiesel are significantly influenced by the fatty acids found in these triglycerides. The fatty acid profile of biodiesel corresponds to that of the feedstock used for its production. Table 16.1 gives the fatty acid profiles for several common vegetable oils. 

Demirbas, A. S. Karslioglu. Biodiesel production facilities from vegetable oils and animal fats. Energy Sources, Part A 2007, 29, 133-141. 

Hirata et al (1987) conducted extensive tests comparing the FA composition of egg yolk after feed supplements of vegetable oil and animal fat. The FA sample of the dietary fat supplement is reflected considerably more clearly in TAG than in polar lipids. Table 14.10B reveals that compared to the supplement of animal fats, the proportion of linoleic acid in the TAG of the egg yolk is highest after a 10% soy oil supplementation, and the proportion of oleic acid the lowest this also applies to a coconut oil supplementation. Furthermore, after coconut oil supplementation, the TAG contain substantially more myristic, myristoleic, and patmitoleic acids. Because myristoleic acid (C14,) and pahnitoleic acid (Cjea) are not present in coconut oil, but do occur in egg yolk lipids, the production of a double bond in myristic and palmitic acids by fat metabolism can be assumed. Although coconut oil consists of 50% lauric acid (C,2 o), only small amounts of this acid can be found in the egg yolk. It has been assumed that hens can use only very small amounts of FA with shorter chains for egg yolk lipid production. Shorter FA in the coconut oil do not contribute to egg yolk FA production. The... 

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