Vegetable oils, refining

There are many types, and only the most important can be mentioned here. [See also Hunter, in Dunstan (ed.). Science of Petroleum, vol. 3, Oxford, New York, 1938, pp. 1779-1797.] They are used fairly extensively in treating petroleum distillates, in vegetable-oil, refining, in extraction of phenol-bearing coke-oven liquors, in some met extractions, and the like. Kalichevsky and Kobe (Petroleum Refining... 

Sometimes natural fine chemicals are by-products in bulk products refining. Examples are (a) lecithin and steroids in vegetable oil refining (b) betaine, pectin and raffinose in sugar manufacture (c) quinic acid in quinine extraction of the bark of Cinchona trees (d) chitin and the red pigment asthaxanthin in lobster and shrimp processing and (e) lanolin, lanosterol and cholesterol in sheep wool purification. 

Uses Stabilizer for latex rubber intermediate for dyestuffs and medicinals resin and detergent manufacturing solvent in petroleum and vegetable oil refining starting material for manufacturing amides plasticizer stabilizer for rubber latex in organic synthesis. 

Watanabe, Y., Pinsirodom, P, Nagao, T., Yamauchi, A., Kobayashi, T., Nishida, Y., Takagi, Y., and Shimada, Y. 2007. Conversion of acid oil by-produced in vegetable oil refining to biodiesel fuel by immobilized Candida antarctica lipase. J. Mol. Catal. B Enzym., 44, 99-105. 

STEROLS Phytosterols are mostly associated with unrefined vegetable oils and exist as derivatives of phenolic acids (e.g., ferulic acid). Several studies are available on antioxidant activity of sterols and their derivatives from sources such as corn fiber, oats, and rice. These compounds can be obtained from the unsa-ponifiable fraction that is removed during vegetable oil refining. Triterpene alcohols and hydrocarbons (131), or sterols (Figure 20) from oats (132, 133), rice (134, 135),... 

Fresh Oil. Fresh frying oil is obtained by refining palm oil or seed oils. It would be appropriate to briefly discuss the vegetable oil refining process for the readers to understand how various processing steps impact the quality of freshly refined oil. Vegetable oils are refined principally by ... 

Any new developments by equipment manufacturers in vegetable oil refining are transferable to rendered fat processing. In-line monitoring of the free fatty acid (FFA) content with automatic addition of the caustic solution followed by mixing and separation by centrifuge has improved refining yields. Some processors have... 

Vegetable lecithins are obtained as a by-product in the vegetable oil refining process. Polar lipids are extracted with hexane and, after removal of the solvent, a crude vegetable oil is obtained. Lecithin is then removed from the crude oil by water extraction. Following drying, the lecithin may be further purified. ... 

About one tenth of the total amount of vitamin E produced is semi-synthetic, isomerically pure (2R,4 K,8 R)-a-tocopherol (RRR-3) which is used almost exclusively in human applications (mainly pharma). This product, originating from natural sources, is obtained from soya deodorizer distillates (SDD). Vegetable oils refined on a large scale are the major sources of vitamin E compounds [26-28]. The deodorizer distillate, originally a waste stream, contains considerable amounts (up to 10%) of a-, [I-, y- and b-tocopherols (RRR-3 to RRR-6) which are isolated by several separation methods. To increase the value of the vitamin E concentrate of mixed tocopherols obtained from SDD, the lower (I-, y- and d-homologues (RRR-4 to RRR-6, content ca. 90%) have to be transformed subsequently into the biologically more active a-tocopherol (RRR-3, only ca. 5% in the original mixture) by permethylation reactions. Permethylations are performed by chloro-, amino-, or hydroxymethylation reactions to provide functionalized alkylated intermediates, which are reductively converted into RRR-3 (Fig. 3) [29]. 

Alternative techniques of vegetable oil refining have been developed. Simple refining methods were explored to process extruded-expelled (E-E) soybean oils with various fatty acid compositions (Wang and Johnson 2001b, 2001c). E-E... 

Verleyen, T U. Sosinska S. loannidou R. Verhe K. Dewettinck A. Huyghebaert W. De Greyt. Influence of the vegetable oil refining process on free and esterified sterols. /. Am. Oil Chem. Soc. 2002b, 79, 947-953. 

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