Lecithin enzymes affecting

Expanders also inactivate catabolic enzymes due to heat, just as cooking does in the ALCON process. Both the expanding and the cooking of flakes increase the levels and types of phosphatides present in the crude oil, but the phosphatides are more hydratable and more easily removed during water degumming. Expanders can affect the quality of edible lecithin, especially in the formation of white haze. Cooked or expanded soybean flakes need to be dried to < 10% before solvent extracting to avoid color reversion (Erickson, 1995a). 

Rape seed represents one of the most important oil seeds in the countries of Central Europe. The annual crop in the Czech Republic is about 1/2 milion of tons and it is the main source for the plant oil production. Rape seed oil contains approx. 0.8 - 3.5% of lecithin (1), the main components of which are phosphatidylcholine (PC), phosphati-dylethanolamine (PE) and phosphatidylinositol (PI). All phospholipids mentioned above are potential substrates for phospholipase D (E.C.3.1.4.4). The product of this enzyme reaction is phosphatidic acid ( nonhydratable phospholipid), which is not readily removed during degumming process and affects flavour of the final product. 

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