Triglyceride saponification

Fatty acid No. C atoms No. double bonds Mol. wt.of acid Mol. wt. of triglyceride Saponification value of triglyceride Iodine value of acid Iodine value of triglyceride... 

There are several soap-making processes which utilize the continuous neutralization of fatty acids. In the MILLS process (McBride, 1947), distilled fatty acids at 75 °C are fed with a metered supply of sodium hydroxide solution to a high-speed mixer. Sufficient sodium chloride is added to the alkali so that the final soap composition is similar to that obtained by the triglyceride saponification route. 

When soap is produced from most triglyceride saponification or fatty acid neutralization soap-... 

The process flow diagram of a typical triglyceride saponification plant is illustrated... 

Eats and oils from a number of animal and vegetable sources are the feedstocks for the manufacture of natural higher alcohols. These materials consist of triglycerides glycerol esterified with three moles of a fatty acid. The alcohol is manufactured by reduction of the fatty acid functional group. A small amount of natural alcohol is also obtained commercially by saponification of natural wax esters of the higher alcohols, such as wool grease. 

MetaUic ions are precipitated as their hydroxides from aqueous caustic solutions. The reactions of importance in chlor—alkali operations are removal of magnesium as Mg(OH)2 during primary purification and of other impurities for pollution control. Organic acids react with NaOH to form soluble salts. Saponification of esters to form the organic acid salt and an alcohol and internal coupling reactions involve NaOH, as exemplified by reaction with triglycerides to form soap and glycerol,... 

Free Fatty Acid and Saponification Value. High concentrations of free fatty acid are undesirable in cmde triglyceride oils because they... 

Carboxylate soaps are most commonly formed through either direct or indirect reaction of aqueous caustic soda, ie, alkaH earth metal hydroxides such as NaOH, with fats and oils from natural sources, ie, triglycerides. Fats and oils are typically composed of both saturated and unsaturated fatty acid molecules containing between 8 and 20 carbons randomly linked through ester bonds to a glycerol [56-81-5] backbone. Overall, the reaction of caustic with triglyceride yields glycerol (qv) and soap in a reaction known as saponification. The reaction is shown in equation 1. 

Japan Wax. Japan wax [8001-39-6] is a fat and is derived from the berries of a small tree native to Japan and China cultivated for its wax. Japan wax is composed of triglycerides, primarily tripalmitin. Japan wax typically has a melting point of 53°C, an acid number of 18, and a saponification number of 217. Principal markets include the formulation of candles, poHshes, lubricants, and as an additive to thermoplastic resins. The product has some food-related apphcations. 

The fatty adds commonly encountered in biological systems are straight chained alkanoic or alkenoic adds, containing an even number of carbon atoms (usually Ch-Ch). natural n Senera / these fatty adds can be produced readily by extraction of the lipids from sources natural sources and saponifying the neutral triglycerides. This is satisfactory providing a mixture of fatty acids is acceptable. Purification of spedfic fatty adds from the saponification mixture increases the costs considerably. 

Fatty acids, respectively the alkali salts of fatty acids, have long been produced by saponification of fats or fatty oils by alkali lye. At present the free acids are produced either by hydrolysis of the triglycerides with water in an uncatalyzed reaction at 210-260°C under a pressure of 20-60 bar or in a cata-... 

Figure 13.16.5 The hydrolysis or saponification of a triglyceride to yield the constituent acids and glycerol.

Generally, alkaline saponification in hydroalcoholic KOH is the most widespread approach [11 13]. This allows us to cleave ester bonds and, if necessary, to separate the saponifiable fraction (acids) and unsaponificable fraction (alcohols, sterols, and hydrocarbons). Generally, 3 h of saponification in 10% KOH in water/methanol (3 1) at 60 °C achieves a quantitative yield for triglycerides. Wax esters are less prone to hydrolysis and generally need stronger conditions. Quantitative hydrolysis of beeswax long chain esters has been obtained using 10% KOH in ethanol assisted by microwaves, for 60 min at 80 °C and at 200 W [21],... 

These reactions, which are believed to occur predominantly inter-molecularly, are capable of producing intermediates which hold some potential as precursors for important chemical products. For example, metathesis of olive oil, which consists chiefly of triglycerides of oleic acid, produces the glyceride of 9-octadecene-l,l8-dioic acid from which can be obtained, after saponification, acidification, and low-temperature crystallization, the free acid, which can be transformed by intramolecular condensation to civetone. 

Applying Concepts The reaction between a triglyceride and a strong base such as sodium hydroxide is called saponification. In this reaction, the ester bonds in the triglyceride are hydrolyzed by the base. The sodium salts of the fatty acids, called soaps, precipitate out, and glycerol is left in solution. 

What type of bonds present in the triglycerides are broken during the saponification reaction ... 

Retinoids The challenge in fat-soluble vitamins analysis is to separate them from the lipid fraction that contains interferents. Alkaline hydrolysis, followed by LLE, is widely applied to remove triglycerides. This technique converts the vitamin A ester to all-trani-retinol. A milder process, which does not hydrolyze vitamin A ester, is alcoholysis carried out with metha-nolic KOH solution under specific conditions that favor alcoholysis rather than saponification. A more accurate explanation of this technique is reported in the book Food Analysis by FIPLC [409]. For some kind of matrices a simple liquid extraction can be sufficient with [421-423] or without [424,425] the purification... 

Natural surfactants, such as soaps, are made by saponification of fats or triglycerides, such as tri-palmitin in palm oil. The main component of common soap is sodium stearate, C17H35COO" Na , which is made from the saponification of animal fats. When dissolved in water, the carboxylic headgroup ionizes and is strongly hydrophilic, whereas the hydrocarbon chain is hydrophobic. The hydrocarbon chain, alone, is almost completely insoluble in water. When dissolved into aqueous solution, the molecules can adsorb and orientate at the air/solution interface, as illustrated in Figure 4.1, to reduce the surface tension of water ... 

In saponification, triglycerides are heated in a basic solution to give glycerol and soap. R represents long carbon chains. 

Again, as with the IV, the saponification value provides some basic information about a lipid system. In a pure system (Table DI.4.3), with a series of triglycerides of increasing chain length, as the chain length increases there is a decrease in saponification value. With triglycerides of the same or close chain lengths,... 

Enzymatic hydrolysis is a nondestructive alternative to saponification for removing triglycerides in vitamin K determinations. For the simultaneous determination of vitamins A, D, E, and K in milk- and soy-based infant formulas and dairy products fortified with these vitamins (81), an amount of sample containing approximately 3.5-4.0 g of fat was digested for 1 h with lipase at 37°C and at pH 7.7. This treatment effectively hydrolyzed the glycerides, but only partially converted retinyl palmitate and a-tocopheryl acetate to their alcohol forms vitamin D and phyllo-quinone were unaffected. The hydrolysate was made alkaline in order to precipitate the fatty acids as soaps and then diluted with ethanol and extracted with pentane. A final water wash yielded an organic phase containing primarily the fat-soluble vitamins and cholesterol. 

The removal of triglycerides from the food sample by saponification provides the opportunity to utilize reversed-phase chromatography. The unsaponifiable matter is conventionally extracted into a solvent [e.g., diethyl ether/petroleum ether (50 50) or hexane] that is incompatible with a semiaqueous mobile phase. It then becomes necessary to evaporate the unsaponifiable extract to dryness and to dissolve the residue in a small volume of methanol (if methanol is the organic component of the mobile phase). For the analysis of breakfast cereals, margarine, and butter, Egberg et al. (153) avoided the time-consuming extraction of the unsaponifiable matter and the evaporation step by acidifying the unsaponifiable matter with acetic acid in acetonitrile to precipitate the soaps. An aliquot of the filtered extract could then be injected, after dilution with water, onto an ODS column eluted with a compatible mobile phase (65% acetonitrile in water). 

Normally, odd-numbered fatty acids are used as internal standards. While the use of internal standards ensures the correctness of the extraction procedure, it does not guarantee the completeness of extraction for different fatty acids. Due to this reason, a comparison between the methods is essential to truly determine the efficacy of extraction. Chavarri et al. (1997) compared two sample preparation procedures. The first method was the direct method developed by de Jong and Badings (1990), described above. The second method involved saponification with TMAH as described by Martin-Hemandez et al. (1988) and the formation of methyl esters in the injector prior to analysis. The authors found that separation of the FFAs from the triglycerides prior to derivatization improved the analysis. Another comparative study by Ardo and Polychroniadou (1999) reported that the saponification method described above (Martin-Hernandez et al., 1988) was found suitable for both low and high FFA levels in cheese. 

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