lecithin and cephalin, with the lecithin fraction predominating. The 

 separation of lecithin frcm the extracted egg fat would appear to be 

 easily accomplished by a process developed by the German oil indus- 

 try and described by Goss (4). In this process the lecithin is re- 

 moved from the crude fat or oil by washing it with 2-5 percent of 

 hot water and removing the resulting sludge in a centrifuge. Two suc- 

 cessive washings are required to insure maximum recovery of lecithin. 

 The lecithin is recovered from the sludge by ronoval of water at 60°C. 

 with the aid of -vacuam followed by a bleaching of the residue with 

 hydrogen peroxide. Residual oil remaining in the lecithin is then re- 

 moved by repeated extractions with acetcwie. 



Recovery of a semi-purified protein of high nutritional quality 

 may have considerable importance in the econanic utilization of salmon 

 eggs. The protein content of salmon eggs varies from about 22 per- 

 cent in king 1/ salmon to about 28 percent in the chum 2/. Although 

 very little information regarding the amino acid ccxitent of salmon egg 

 protein has appeared in the scientific literature, an investigation of 

 the protein of the casings of salmon eggs was reported in 1938 by 

 Young and Inraan (ll). They found that the protein in the egg casing 

 was insoluble in the ordinary protein solvents and was slowly hydro- 

 lyzed by pepsin. On ana lysis the protein yielded the following values 

 Expressed in percentage of the moisture- and ash-free material: total 

 nitrogai, 15. 3; cystine, 1.84; tryptophsme, 5.79; and glucosamine, 1.04. 

 The casing constitutes 6.2 percent of the weight of the unfertilized 

 egg. Hugouneng (6) in 1906 reported an analysis of an albumin extract- 

 ed from the eggs of herring. Upon hydrolysis, the albumin, termed 

 "clupeovine," yielded arginine, histidlne, lysine, tyrosine; leucine,, 

 valine, alanine, seirLne, i^enylalanine, and aspartic acid. Comparing 

 this protein with vitellin from hens' eggs, Hugouneng found the products 

 formed to be identical and he concluded that probably the two proteins 

 are built upon the same plan. 



The quantities of salmon eggs available in Alaska for processing 

 are enormous. Since the eggs ccsistitute about 8 to 10 percent of the 

 entire salmon cannery waste, vdiich amounts to more than 100,000,000 

 pounds annually, it can be readily calculated that about 9,000,000 

 pounds or 4500 tcHis of salmon eggs are at present discarded each year. 



Collection of the raw salmon eggs in Alaska should not interpxjse 

 any difficult problems. The salmon are dressed prior to canning in a 

 machine known as the "Iron Chink" which cuts off the head, fins and 

 tail and removes the viscera. The eggs, as a part of the viscera, are 

 swept out of the body cavity in the middle cycle of the rotating wheel 

 of the "Iron Chink." Separation of the eggs frcsn the rest of the ab- 

 dominal contents would necessitate hand sorting only to a moderate 

 degree. The large, and in most cases, intact skeins of salmon eggs 



1/ King Salmon - Oncorhynchus tachawytcha . 

 2/ Chxim salmon - Oncorhynchus keta. 



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