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Food Lipids: Chemistry, Nutrition, and Biotechnology

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Figure 51 Principle of enzymatic degumming of oils <strong>and</strong> fats using phospholipase A 2 for<br />

converting diacylglycerophospholipids to easily hydratable lysophospholipids.<br />

imately 5.0. The resulting mixture, maintained at a temperature of 60�C, is intimately<br />

mixed with the enzyme solution (enzyme concentrate diluted with water to 0.2%<br />

v/v) <strong>and</strong> passed through two or more enzyme reactors. The residence time of the<br />

mixture in the reactors varies from 1 to 6 hours, depending on the phosphatide<br />

content of the starting material <strong>and</strong> the quality requirement on the degummed oil.<br />

The effluent from the enzyme reactors is finally admitted to a separator to obtain the<br />

streams of degummed oil <strong>and</strong> aqueous phase containing the phosphatide sludge containing<br />

the still active enzyme that is generally reused several times by recycling<br />

into the process.<br />

Operational data from commercial plants for degumming of 540 tons/day rapeseed<br />

oil <strong>and</strong> 400 tons/day soybean oil show a likely average consumption of 10 g<br />

enzyme concentrate per ton of oil <strong>and</strong> residual phosphorus content of the degummed<br />

oil less than 10 ppm. The enzymatically degummed oil can be subjected to physical<br />

refining after bleaching. Due to low phosphorus content <strong>and</strong> absence of soaps enzymatically<br />

degummed oils, as compared with those obtained by other degumming<br />

processes, can be bleached with st<strong>and</strong>ard bleaching earths instead of high activity<br />

<strong>and</strong> acidic bleaching earths. Additional economic advantages of enzymatic degum-<br />

Figure 52 Flow sheet of the commercial EnzyMax process for degumming oils using<br />

phospholipase A 2. (From Ref. 374.)<br />

Copyright 2002 by Marcel Dekker, Inc. All Rights Reserved.

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