Commercial Shark Fishing in the Caribbean Area 33 



should be well protected for a period of one or two 

 months. 



(2) Aquacide. Aquacide is a commercial product 

 specifically prepared to preserve livers. Full informa- 

 tion regarding this product may be obtained from the 

 Aquacide Company, 724 Eleventh Street, N.W., Wash- 

 ington, D. C. Information concerning similar products 

 may be obtained from British Colloids, Ltd., Port Royal, 

 London, N.W., 10; Glaxo Laboratories, Ltd., Green Ford; 

 and Lever Brothers, Port Sunlight, England. However, 

 for commercial purposes either one of the other methods 

 described here will be satisfactory. 



(3) Soda ash and sodium nitrate. This method can be 

 used only when you can get the necessary equipment and 

 material, but it is probably the most effective. First 

 make a mixture of 90 percent soda ash and 10 percent 

 sodium nitrate. Put this into a solution with an equal 

 volume of water. Five percent of this solution is then 

 added to livers which have been washed and thoroughly 

 ground. The liver and preserving mixture are then 

 packed in wooden or metal containers. 



Extracting the Oil 



You can extract the oil from small lots of: livers very 

 inexpensively by using a double boiler. Place chopped 

 livers in the inner boiler and add a little water. Heat 

 for about 45 minutes. The liver tissue will break down 

 and the oil will be set free. On standing, the oil will rise 

 to the surface where you can skim it off. I he oil which 

 is obtained, however, is not as rich in Vitamin A or as 

 valuable as oil which is obtained by the f ollowing method. 



This second method is not recommended unless the 

 number of sharks caught is large enough to cover the 

 costs of the expensive equipment which would be neces- 

 sary. If you can use this method profitably, however, you 

 would get more oil and Vitamin A from your catch than 

 by the other processes of preserving the livers, and of 

 course you would be able to ship oil much more cheaply 

 than entire livers. 



If you can and wish to build a rendering plant such 

 as would be necessary for this process, more complete 



