Deodorizer distillate fraction

Supercritical fractionation of a liquid lipid feed material is usually carried out in a packed column. Standard columns are not available commercially and have to be custom built either in-house or by manufacturers of extraction units. Lab-scale and pilot-scale supercritical columns, 0.6-13.6 m high with internal diameters of 14.3-68 mm are available in research labs around the world and have been used for the processing of deodorizer distillates (56, 57, 86-90), vegetable and fish oils (91-105), cocoa butter, and milkfat (106-109). A schematic diagram of a typical SCCO2 fractionation column (2.8 m, 2.54 cm o.d.), which was designed and built... 

SCCO2 fractional extraction of soybean deodorizer distillate using an extractor with a reboiler at the bottom and obtained 83.6% tocopherol recovery at the optimal conditions of 31.03 MPa, 363 K top, and 343 K bottom temperature. Free fatty acids and squalene were concentrated in the extract together with tocopherols, whereas sterols were concentrated in the raffinate. 

Supercritical CO2 column fractionation of soybean (57, 86, 88, 89) and rice bran oil (57) deodorizer distillates has been investigated to enrich their sterol and tocopherol contents. Brunner et al. (89) reported that the FFA were enriched in the top (in the extract), whereas the monoacylglycerols, tocopherols, and diacylglycerols were enriched in the bottom (in the raffinate) fraction during the fractionation of soybean oil deodorizer distillate. Saure and Brunner (88) achieved a tocopherol concentration of more than 70% (w/w) using continuous column fractionation of soybean deodorizer distillate where squalene was almost completely found in the top product, whereas sterols and tocopherols were enriched in the bottom product. King and Dunford (57) developed a two-step column fractionation scheme (13.6 MPa and 27.2 MPa at 313 K) for the enrichment of phytosterols from soybean and rice bran oil deodorizer distillates such that the FFA were removed in the first step and sterols were enriched in the oil fraction in the second step. 

Supercritical CO2 column fractionation has also been investigated for the production of squalene concentrates from olive oil deodorizer distillates (56, 87). Bon-dioli et al. (87) used saponification and esterification steps to convert the FFA and fatty acid esters to triacylglycerols in order to improve squalene separation prior to countercurrent continuous fractionation. The highest squalene purity and extraction yield was achieved at 15 MPa and 313 K, using a temperature gradient of 303-323 K along the column to improve the squalene purity and yield. Ruivo et al. 

S.3.2.2. Pretreatment for Fractionation and Anaiyticai Purposes Chemical reactions can be used to modify the composition of a lipid mixture to facilitate its fractionation. As mentioned previously, such approaches have been employed in the fractionation of soybean (117) and olive oil deodorizer distillates (87) and fish oils (97). However, although the fractionation steps in these studies were carried out under supercritical conditions, the use of SCCO2 as a reaction medium in the pretreatment reactions has not been explored. Gunnlaugsdottir et al. (151, 165-168) investigated the alcoholysis of cod liver oil in SCCO2 for the concentration of fatty acids such as EPA and DHA. A process for the purification of polyunsaturated fatty acids from biomass on an analytical scale using in situ SEE/SCF reaction and chromatography has been patented (215). 

The concentration of sterols, di- and triglycerides in the extract fractions was lower than the respective feed concentrations under all of the investigated operating parameters the distribution of other components was affected by fractionation time, temperature and pressure. The volatiles were enriched up to a factor of 6.3, but the decrease in volatile concentration with time resulted in concentrations lower than the feed values in the latter fractions. The free fatty acids were enriched in the latter fractions relative to their concentration in the feed. Semi-continuous processing of the deodorizer distillate at 25 MPa and 70-100°C yielded a residue containing 40% sterols and this study highlights the value of using the canola deodorizer distillate as a source for the extractiou of phytosterols. 

Gil lu-Ustundag, O. and Temelli, F. 2007. Column fractionation of canola oil deodorizer distillate using supercritical carbon dioxide, J. Amer. Oil Chem. Soc. 84 953-961. 

King JW, Dunford NT. 2001. Phytosterol-Eniiched Triglyceride Fractions from Vegetable Oil Deodorizer Distillates Utilizing Supercritical Fluid Fractionation Technology. Separation Science and Technology 37(2) 451-462. 

Pine Oil. This oil is obtained by extraction and fractionation or by steam distillation of the wood of Pinuspalustris Mill, and other species. Most of the oil is produced ia the southeastern United States. The composition of the oil depends on the fractions chosen, but the chief constituents are terpene alcohols, mainly terpiaeol. Piae oil finds use as a germicide ia disiafectants and soaps as an ingredient ia iasecticides, deodorants, poHshes, sweepiag compounds, and catde sprays and as raw material for the manufacture of perfumery-grade terpiaeol [8000-41 -7], anethole [104-46-1], fenchone (137), and camphor (35). 

After acidification, the lipid fraction is extracted into hexane and the solvent subsequently removed by evaporation. This gives a material consisting of 60-75% (w/w) CLA (depending on the starting materials), with the remainder consisting of unchanged saturated and monounsaturated fatty acids from the starting material. Deodorization of CLA removes volatile compounds such as hexane that may be residual solvent or secondary autoxidation products from CLA. Fractional distillation and crystallization remove metal catalysts (which may stimulate oxidation), as well as undesirable components such as dimers and polymers. The reactor type will affect the amounts of metals found. 

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