Fatty acids, fixed oils

Properties (Commercial grades) Yellow to red oily liquid lardlike odor, darkens on exposure to air. Insoluble in water soluble in alcohol, ether, and most organic solvents, fixed and volatile oils. Solvent for other oils, fatty acids and oil-soluble materials. (Purified grades) Water-white liquid. D 0.895 (20/4C), fp 4C, bp 286C (100 mm Hg), 225C (10 mm Hg), refr index 1.4599 (20C), acid value 196-204, iodine value 83-103, saponification value 196-206, flash p 372 (189C), Combustible. 

Characterisation of volatile oils (which may be used as excipients in formulations), proprietary cough mixtures and tonics, and fatty acids in fixed oils. 

The BP monographs for many of the fixed oils contain a GC analysis to confirm the content of the fatty acids composing the triglycerides (fatty acid triesters of glycerol) present in the oil. The monograph for almond oil states the composition of the fatty acids making up the triglyceride should be ... 

Lipids are esters of long-chain fatty acids and alcohols or of closely related derivatives. The chief difference between these substances is the type of alcohol in fixed oils and fats, glycerol combines with the fatty acids in waxes, the alcohol has a higher molecular weight, e.g., cetyl alcohols. 

In order to overcome the existing problems with the state-of-the-art technology in vegetable oil and free fatty acid hardening, we have investigated hydrogenation reactions in liquid, near-critical, and supercritical C02, as well as C02/propane mixtures with precious-metal fixed-bed catalysts supported on acid-resistant supports. 

The catalytic activity is measured by determining the amount of free fatty acids formed over a fixed time interval from an oiive oil emuision, at 37 C, pH 7.0, and in the presence of 0.025% (final concentration) of sodium taurocholflte. 

The saponifiable portion of the fatty oil accounts for about 90% of the total fixed oil and is characterized by a very high content of octadecenoic acids. Petroselinic and oleic acid occur at similar levels and jointly comprise 74-85%, linoleic 7-16% and palmitic 4-8%, of the constituent fatty acids. During prolonged storage of the spice, the free fatty acid content gradually increases and this is a good indicator of the age of the material. The contents of fatty acids, sterols and total tocopherols in a deodorized oil derived from coriander seeds (yield up to 28%) are compared with those in sunflower oil and tests on the biological effects of coriander oil are reported by Mironova et al. (1991). Of the fatty acids present, total C18 1 acids (petroselinic acid + oleinic acids) constituted 80—82% and petroselinic acid alone 50—60%, and the food value was lower than that of sunflower oif. Kim et al. (1996) found the production of petroselinic acid from cell suspension cultures of C. Sativum. 

Of the fatty acid in the fixed oil, most of which is contained in the polygonal cells in the seed endosperm, total monounsaturated acids account for 10% and total polyunsaturated fatty acids 2%. The main components of an expressed oil are petroselinic acid (up to 75%), oleic acid (up to 25%), linoleic acid (up to 15%) and palmitic acid (up to 5%) (Weiss, 2002). 

The seeds contain about 7% fixed oil consisting mainly of linoleic, oleic and lino-lenic acids. Fenugreek seeds from Andhra Pradesh contained 5.00-6.45% fatty oil (Ramachandraiah et al., 1986). Hot alcohol was reported as the best solvent for extract-... 

Ambrette Seed Oil occurs as a clear yellow to amber liquid with the strong, musky odor of ambrettolide. It is a volatile oil obtained by steam distillation from the partially dried and crushed seeds of the plant Abeltnoschus moschatus Moench, syn. Hibiscus abeltnoschus L. (Fam. Malvaceae). It is refined by solvent extraction to remove fatty acids or by precipitation of the fatty acid salts. It is soluble in most fixed oils and in mineral oil, often with cloudiness, but relatively insoluble in glycerin and in propylene glycol. 

It is a complex mixture of acetone-insoluble phosphatides that consists chiefly of phosphatidyl choline, phosphatidyl ethanolamine, and phosphatidyl inositol combined with various amounts of other substances such as triglycerides, fatty acids, and carbohydrates. Refined grades of Lecithin may contain any of these components in varying proportions and combinations depending on the type of fractionation used. In its oil-free form, the preponderance of triglycerides and fatty acids is removed and the product contains 90% or more of phosphatides representing ah or certain fractions of the total phosphatide complex. Edible diluents, such as cocoa butter and vegetable oils, often replace soybean oil to improve functional and flavor characteristics. Lecithin is only partially soluble in water, but it readily hydrates to form emulsions. The oil-free phosphatides are soluble in fatty acids, but they are practically insoluble in fixed oils. When ah phosphatide fractions are present, Lecithin is partially soluble in alcohol and practically insoluble in acetone. 

This procedure is used to determine the lipase activity in preparations derived from microbial sources. The assay is based on the measurement of the amount of free fatty acids formed from an olive oil emulsion in the presence of sodium taurocholate over a fixed time interval. This assay is particularly used for measuring lipase activity in foods. 

Edible oils and fatty acid esters were selectively hardened in sc CO2 at temperatures between 60°C and 90°C and at a total pressure of 10.0 MPa. In order to get different degrees of hardening, we investigated activated carbon and different DELOXAN supported precious metal fixed bed catalysts at space velocities (LHSV) between 5 and 60 h1. 

The annual capacity of the extraction unit was fixed in 10 kton of virgin olive oil with an average composition in free fatty acids of 4 wt%. Although this composition may change with the harvesting year it was taken as a mean value for the intake oil. The extraction process is intended to reduce the residual concentration of FFA to a value less than 0.7 wt%. 

When gas chromatography became established as an analytical technique, certain classes of metabolite proved particularly amenable to study. These were volatile oils (see monoterpenes), the constituents of leaf surface waxes and, in the form of their methyl esters, the fatty acid components of fixed oils and fats, particularly those occurring in seeds. Structural variation within each of these t)q)es of compound proved to be somewhat less pronounced than with many other groups of metabolites. Nevertheless, the classification of plant families on the basis of the chain length and degree of unsaturation of the predominant fatty acids was proposed (Smith, 1976). 

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