Iso oleic acid

A Linoleic acid C Iso-oleic acid B cis-oleic acid D Stearic acid... 

Iso-oleic Acid.—It should also be mentioned that a third isomeric ethene unsaturated acid of this composition is known, viz., iso-oleic acid. The isomerism in this case is probably structural and consists in a change in the position of the double bond, which is considered to be between carbon atoms two and three, viz., CH3—(CHo)i4—CH=CH— COOH. Oleic acid was discovered by Chevreul in 1846. It is a clear colorless oily liquid without odor or taste and is easily oxidized in the air. On cooling it solidifies to a white crystalline mass melting at 14 . Under a pressure of 10 m.m. it boils at 223 but distills without decomposition at 250° with superheated steam. It differs from the higher saturated acids in yielding a lead salt which is easily soluble in ether, thus affording a method for its separation and isolation. Elaidic acid is a solid melting at about 45°. 

Concurrently with hydrogenation, certain isomerization reactions invariably occur of these, the one of greatest importance is the conversion of natural low-melting oleic acid which has the cis form to elaidic acid or other high-melting Irans forms generally referred to as iso-oleic acids. 

HDZ = hydrazine Igepal CO-520 = polyoxyethylene(5)nonylphenyl ether ISO = isooctane LAc = linoleic acid MA = methylamine MST = mesitylene Ni°(cod)2 = bis (r]4-l,5-cyclooctadiene) Ni(0) NMPyr = N-methylpyrrole OA = oleylamine OAc = oleic acid Oc = octane OcA = octylamine ODA = octadecylamine PAA = poly (acrylic add) PD = 2-pyrrolidone Igepal CA-520 = polyoxyethylene(5)isooctylphenyl ether PVP = polyvinylpyrrolidone Pyr = pyrrole RAc = ricinoleic acid ... 

Fig. 21.15. Partial gas chromatogram of extracted lipids. Peaks Ci4 0 to Ci8 o> saturated straight fatty chain acids (FA) with 14 to 18 carbon atoms C45br and Ci7 r, iso- and anteiso- branched-chain fatty acids Ci8 i FA, mono-unsatu-rated CigtoOH-FA, hydroxylated form derived by bacterial hydration of the original oleic acid. (Reprinted/redrawn from Nature, 432, 35-36, Copyright 2004, Nature Publishing Group, with permission.)...

In the mid-sixties, Atlas Chemical Industries investigated the reaction of epoxides with isohexides. Transformation of isosorbide (3) by ethylene oxide affords polyoxyethylene isosorbide (62), which was treated with oleic acid to afford the corresponding diesters (63), and these were further transformed into epoxidized products167 (64) (see Scheme 12). On treating all three iso-... 

Crude oils may be up to 15% FFA, while refined oils will be <0.1%. Measurement of FFA is normally done by titration of an ether-ethanol solution of the fat with standardized aqueous sodium or potassium hydroxide, in the presence of phenolphthalein indicator (see ISO 660 1983). This method is very accurate, using the molecular weight of oleic acid (282) for all calculations. Accuracy is improved by using the average molecular mass of the fatty acids in the fat, calculated from the FA composition (e.g., for palm oil 256 is used, for palm kernel/coconut oil 200 is used). The results are expressed either as acid value the number of milligrams of potassium hydroxide required to neutralize 1 g of the fat, or, FFA% the percentage concentration of oleic acid equivalent to the free acids present. 

Iso-octane, pentane or hexane will extract only a small amount of beer compounds together with the iso-alpha acids. The evaporated extract consists of about 40-50 % iso-alpha acids. Epoxidized and hydroxylated oleic acids are also extracted (about 15 mg.r beer). The remaining material is of unknown composition. When beer is extracted (shaken) with an equal volume of a hydrocarbon solvent, the organic layer mostly turns into a very solid emulsion. This must of course be avoided by using a relatively large volume of the hydrocarbon (2.5 times as much as the beer volume). 

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