436 



MARINE PRODUCTS OF COMMERCE 



Table 94. Average Composition of Fresh Pacific Salmon and Steelhead Trout. 



Species 



Chinook (king) 



Sockeye (red) 



Coho 



Pink 



Chum 



Average all 



species of 



salmon 

 Steelhead trout 



No. Indi- 

 vidual 

 Fish 

 Analyzed 



204 

 130 



99 



90 

 120 



643 



32 



Moisture 



% 



63.53 

 64.52 

 66.26 

 69.24 

 68.95 



66.50 

 61.80 



Ether 



Extract Protein 

 or (NX 6.25) 

 Fat 



13.50 



10.84 



9.47 



6.16 



7.42 



9.48 

 14.83 



19.48 

 20.67 

 20.40 

 20.56 

 20.83 



20.39 

 20.46 



Total 

 Ash 



2.85 

 2.97 

 3.15 

 3.47 

 2.40 



2.97 

 2.33 



Salt- 

 free 

 Ash 



1.18 

 1.29 

 1.22 

 1.32 

 1.24 



1.25 

 1.20 



' Calculated by factors of Rubner: 18.6 Cal. for 1 per cent 

 1 per cent fat, on the basis of 1 pound. 



Calories ^ 

 per lb. 



931 

 841 

 778 

 642 

 700 



778 

 1006 



protein, and 42.2 Cal. for 



* No appreciable difference is found between canned and fresh salmon, as the com- 

 position of canned salmon is used here. 



greatly, both within each species and between the different species, and so from 

 the standpoint of energy the food value differs greatly. The chinook and sockeye 

 salmon and the steelhead trout possess the most oil and, therefore, the highest 

 food value. When all canning districts are considered, however, many parcels of 

 coho and pink salmon have a higher food value than the average of either of the 

 first 2 species. 



Bacteriology of Salmon. The spoilage of fresh salmon has been extensively 

 studied by both the U. S. Bureau of Chemistry and the Seattle Laboratory of the 

 National Canners Association. The decomposition of mature salmon is due to a 

 large number of species of bacteria; while the decomposition of immature and 

 feeding salmon appears to be largely enzymatic, at least in the early stages, fol- 

 lowed by general bacterial invasion. The most common organisms isolated by 

 Fellers and Hunter and responsible for salmon spoilage are certain species normally 

 occurring in sea water. 



Since many of these bacteria produce indol from certain amino acids formed 



