Methods of manufacture 



Cholesterol is generally prepared by saponification of the oil in 

 which it is contained followed by extraction and purification with sol- 

 vents, lilien vegetable oils are used the resulting nonsaponifiable mate- 

 rial is largely cholesterol and can be used directly in the semi-puri- 

 fied form. 



Lecithin is prepared in a number of ways. One commercial method 

 removes lecithin and other phospholipids by eir'ulsifying the oil with hot 

 water and then desludging the mixture by means of a high speed centrifuge, 

 the lecithins being recovered from the aqueous phase. 



Unsaturated fatty acids are usually prepared by fractional distilla- 

 tion although recently a process based on selective crystcllization of the 

 acids from organic solvent solutions has become of importance. 



Economics of manufacture 



Not a great deal of information is available on this phase of the 

 problem. While it is true that the present market prices of cholesterol 

 and other special substances are relatively high, it is believed that 

 this is only a temporary situation and that reports of new processes 

 being put into commercial production will definitely cause these seem- 

 ingly high prices to fall. Competition will exist between many animal 

 and vegetable b^^roducts from which these special substances can be isolated. 

 For example, spinal cords and wool grease as sources of cholesterol will 

 no doubt be widely used since they are rich sources of the material. 

 Oils which are valuable as fat and which contain only a small percentage 

 of cholesterol would obviously not be used for its manufacture. Lecithin 

 is used in carload quantities; however, its production on a large scale 

 from soybean oil is well founded and it is doubtful if any other material 

 could compete unless it was found to be a very rich source. 



As far as is known, the production of the higher unsaturated fatty 

 acids has not yet been developed on a commercial scale. 



Possibility of utilizing salmon cannery waste for 

 fat, lipid, and cholesterol production 



Location in oalmon Cannery t'^Jaste 



Some parts of the salmon cannery waste are much richer in certain 

 of the lipids than are others. The salmon head with adjoining collar 

 section contains a relatively high percentage of oil. Salmon flesh 

 yields a light colored oil in fair amount. Salmon viscera yields a lesser 

 amount of oil which has some value for animal feeding because of its 

 vitamin A content. Salmon eg :s yield a light colored oil which is very 

 highly unsaturated chemically and which, with possibly only slight 



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