De-oiled lecithin

It is possible to remove the soy bean oil in order to produce a de-oiled lecithin but in confectionery use there is little point in using a de-oiled product. Chemical modification of lecithins is possible but this would cause them to lose their natural status. Another way of modifying the properties is to fractionate the raw lecithin in order to yield products that are richer in one of the components. The resulting products, of course, retain their natural status. 

Soybean lecithin is the predominant source of food and pharmaceutical lecithin because of its availability and outstanding functionality. The composition of crude soy lecithin is shown in Table 14. As a result of the presence of a large amount of neutral oil, crude lecithin is usually de-oiled to improve its functionality. De-oiling is based on the solubility difference of neutral and polar lipids in acetone, in which the phospholipids are precipitated and separated. Alcohol fractionation of de-oiled lecithin can further separate lecithin into an alcohol-soluble fraction that is enriched with phosphatidylcholine and an alcohol-insoluble fraction enriched with phospha-... 

Producing de-oiled lecithins. De-oiled lecithin represents a special category where high phospholipid content (above 95% Al) is required. When contacted with acetone, phospholipids precipitate as a fine, free-flowing powder. After removing the acetone, de-oiled lecithins are dry powders or granules (33). 

As the tocopherols are removed from the lecithin during the extraction process, the de-oiled lecithin has less oxidative stability than the crude product. Also, the surface/volume ratio of the de-oiled lecithin contributes to reduced stability. Mixed soy tocopherols are usually added back at a level of 500 ppm to prevent this. A small percent of an anticaking agent may also be added to ensure that the product remains free-flowing. A free-flowing de-oiled lecithin can be easily added to other products (33). 

Refined de-oiled lecithin can also be blended with carriers such as cocoa butter, hard butters, medium-chain triglycerides, or other diluents to obtain products with more functionality and different physical characteristics. Up to 40% phospholipids may be incorporated in these carriers without the use of solvents. These products are usually stabilized against autoxidation by the addition of antioxidants (33). De-oiled lecithin should be packaged as soon as possible to prevent moisture... 

Another novel de-oiling process has been described by Wendel (158) wherein supercritical gases are used to produce de-oiled lecithin. The cmde lecithin is fed into a column where the supercritical gas mixture of propane and carbon dioxide flows at a pressure of 80 bar and temperature between 40% and 55°C. This fluid then goes to a regeneration column where the temperature is increased to 75°C, and the lecithin component precipitates and falls to the bottom of the column. As the lecithin falls, it encounters pure supercritical extraction fluid and the oil component is extracted. Oil-rich solvent leaves the top of the column. Through pressure and temperature changes, the lecithin and the oil are precipitated out of their respective streams and continuously removed from the process flow. The oil-free, lecithin-free solvent is returned to the column for reuse. 

De-oiled lecithin is also recommended to increase the lubricating properties of reduced fat dough. It helps reduce stickiness for improved production yields and reduce stress on pumps, belts, and motors. 

Enzyme-hydrolyzed lecithin has been shown to improve the heat stability of recombined milk products (233, 234), and almost all infant formulas contain either hydrophilic or de-oiled lecithins as fat emulsifiers (235). Other dairy applications in which lecithins are used include frozen desserts, whipped toppings, and yogurt. 

Producing bland fluid lecithins is possible by redispersing the de-oiled lecithin in clean oils that have been properly refined and deodorized. Lecithin flavors are not typically a problem in food applications because lecithins are used in most foods at low levels. Laboratory tests have shown that in finished food formulations, lecithins can either accentuate or reduce the flavor intensity of salt, acids, and some spices. However, lecithin flavors can penetrate bland dairy-based systems. Studies have shown that 0.25% de-oiled lecithin could be detected in cottage cheese (31). 

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... 

The new process involves the production of de-oiled lecithin by subjecting crude lecithin to supercritical CO2 extraction. The soy bean oil dissolves in CO2 and lecithin does not. One of the examples relates that 1,000 g of cmde lecithin is extracted with CO2 at 60 °C and 400 aun for 4 hours. The CO2 extracts 380 g of a yellow, clear oil, 30 g of water, and the residual material, 580 g of a solid, light yellow substance, which is the deoiled lecithin, is removed from the extraction vessel at the end of the cycle. 

American Lecithin Company s high grade, unmodified, de-oiled Lecithins come in three types of granulation. These granules/ powders are slightly yellow-tan in color. They contain a high level of natural, functional Lecithin Phospholipids. These products conform to the Food Chemicals Codex. 

Components Standard liquid De-oiled lecithin lecithin powder PC-enriched fraction... 

Chem. Descrip. De-oiled lecithin FCC CAS 800243-5 EINECS/ELINCS 232-307-2... 

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