Lecithin phosphatidyl choline fraction

Figure 5. GPC chromatograms of phosphatidyl choline fraction of soya lecithin (conditions same as for Figure 4 except injection volume 50-250 pJL)...

The chromatogram of the commercial soya lecithin as shown in Figure 4 suggests a number of components and all subsequent work was done with the ethanol-soluble fraction, i.e., phosphatidyl choline, or the ethanol-insoluble fraction, comprised primarily of other phosphatides. 

Figure 7. Effect of sample size on apparent molecular weight for soya lecithin phosphatide fractions (conditions same as for Figures 5 and 6 (O) ethanol-soluble fraction (phosphatidyl choline), oligomer GPC (%) ethanol-soluble fraction (phosphatidyl choline), "main column (l ) ethanol-insoluble fraction (other phos-p hat ides), "oligomer GPC (A) ethanol-insoluble fraction (other phosphatides),...

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. 

Lecithin, a mixture of phosphatidyl choline, phosphaddyl ethanolamine, and phosphatidyl inositol, is used as a surfactant in many food, pharmaceutical, and cosmetic products. Lecithin is a product of soy bean oil degumming operations. It is obtained from the hexane extract of flaked soy beans which contains the seed oil and a portion of the phosphatides that are initially present in the soy bean membrane. The exhact is seated with water at 80 °C, and the phosphatides are hydrated rendering them oil insoluble which makes it easy to filler them from the oil. This oil insoluble fraction is termed cmde lecithin and consists of about 70% phosphatides and 30% oil. De-oiled lecithin is obtained by treating the cmde lecithin with acetone. Lecithin is insoluble in acetone and the oil is, and a separation into a 90 to 9r phosphatides fraction can be achieved quite readily. The prior... 

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