Table 4. — Proximate Analysis of Salmon Eggs 



Species of u • j. 

 Salmon Moisture 



Ash 



Percent Percent Percent Percent 



Pink 59.5 27.1 11.1 2.3 



Red 54.7 26.4 13.9 1.8 



Chum 55.4 28.8 11.9 2.7 



King 62.2 22.5 12.8 1.5 



Coho 60.3 25.7 11.4 1.3 



1/ Protein equals total kjeldahl nitrogen x 6.25 



2/ Ethyl ether soluble lipide after acid hydrolysis of sample. 



Solvent extraction of salmon eggs - preparation of protein meal. 



After completion of the proximate analysis of the salmon eggs 

 of various species, it was decided that fairly large quantities of 

 egg protein and fat should be prepared by the acetone solvent ex- 

 traction method described briefly above. Approximately 40 pounds of 

 pink salmon eggs were thawed and ground in a meat chopper through a 

 plate with l/8-inch holes. Four parts by volume of acetone were add- 

 ed and the mixture stirred interriittently over a period of 4 hours. 

 Continuous stirring of the mixture would doubtless reduce the time re- 

 quired for efficient extraction. The undissolved solid niatter was allow- 

 ed to settle out and the liquid phase was separated by decantation. The 

 acetone extraction was repeated three times followed by a final trea-J,- 

 ment with ethanol at a temperature of 76-78°C. Fitial traces of solvent 

 were ranoved from the dehydrated-defatted residue by evaporation in a 

 vacuum desiccator using a water trap immersed in dry ice between the 

 desiccator and the vacuum pump. The nearly colorless, odorless, fine, 

 light powder was found to be not deliquescent. However, in order to 

 maintain these samples without change for use in subsequent studies, 

 they were vacuum packed (25 inches va.) in tin cans. 



Analysis of the dehydrated-defatted salmon egg powder for pro- 

 tein, fat (ether extract after acid hydrolysis) moisture (vacuum oven — 

 28 inches — 5 hours at 80 C), and ash are given in Table 5. 



Table 5. — Composition of dehydrated-defatted salmon egg meal . 



Species of 



Salmon Moisture Protein 1/ Fat 2/ Ash 



Percent Percent Percent Percent 

 King 9.76 84.1 2.45 3.13 



1/ Total nitrogen x 6.25 



2/ Fat determined as ether extract after acid hydrolysis. 



74 



