Detergent fractionation

Detergent Fractionation - The oil is crystallized on its own similar to the dry fraction technique, but separation is affected by employing an aqueous detergent solution and centrifugation. 

The principle of oil fractionation is based on the difference in solubility of the component TAGs. The difference in solubility is directly related to the types of TAGs in the fats and oils. Three major processes are employed commercially to produce value-added fractionated fats and oils (1) dry fractionation, (2) solvent fractionation, and (3) aqueous detergent fractionation. 

In detergent fractionation, an aqueous detergent solution (5% sodium lauryl sulfate) is added to the crystallized material to assist in the separation of the liquid olein and the solid stearin fractions. The separation of the two phases can be... 

This process involves partial crystallization under controlled conditions and separation of the remaining liquid from the solidihed part. Dry, solvent, and detergent fractionations are normally used in this system. The hrst system is the simplest separation it involves cooling the oil to a desired end temperature and then hltering the liquid oil on a vacuum hlter or in a membrane press hlter. The latter two systems, involving solvent or detergent separation of the crystallized phase from the liquid phase, are not widely used, due to their high production costs, capital investments, and contamination. 

Detergent Fractionation—a wetting agent, usually sodium lauryl sulfate, in combination with an electrolyte, usually magnesium sulfate, is added to the crystallizing oil or fat to allow the crystals to be suspended easily in the aqueous phase. The water phase with the crystals is separated from the liquid phase by means of... 

FIGURE 20.3 Schematic representation of the differential detergent fractionation procedure applied to cultured cells. Four fractions are obtained (1) cytosolic proteins, (2) membrane/organelle proteins, (3) nuclear-membrane proteins, and (4) cytoskeletal proteins. (Modified from Fazal, M. A., et al., J. Chwmatogr. A, 1130, 182-189,2006.)... 

FIG U RE 20.5 Two-dimensional eleciropherogtams of each differential detergent fraction. The digitonin fraction (A) is the cytosolic proteins, the Triton fraction (B) is the membrane/organelle proteins, the Tween fraction (C) is the nuclear-membrane proteins, and the detergent resistant fraction (D) is the eytoskeletal proteins. (Reprinted from Fazal,M. A., etal.,7. Chromatogr. A, 1130,182-189, 2006. Copyright 2006. With permission from Elsevier.)... 

Ramshy, M. L., Makowski, G. S., and KhairaUah, E. A., Differential detergent fractionation of isolated hepatocytes Biochemical, immunochemical and two-dimensional gel electrophoresis characterization of cytoskeletal and noncytoskeletal compartments. Electrophoresis, 15, 265-277,1994. 

Figure 17 Schematic layout of a detergent fractionation plant.

Figure 18 Detergent fractionation (a) crystal slurry (b) crystal slurry contacting aqueous detergent and crystals moving into the aqueous phase (c) olein separating into droplets (d) olein droplets coalescing into a continuous oil phase.

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