MAINE SARDINE INDUSTRY. 

 COMPOSITION OF THE SEA HERRING. 



15 



The average composition of the fresh herring, as determined from 

 results obtained throughout the season, is given in Table 3. 



Table 3. — Average composition of sea herring. 



Herring. 



Water. 



Protein. 



Fat 

 (ether 

 extract). 1 



Ash 

 (mineral 

 matter). 





Per cent. 

 72.5 

 68.5 



Per cent. 

 19.5 

 14.3 



Per cent. 

 6.5 

 16.0 



Per cent. 

 1.5 



Fat 



1.2 







1 The fat content of these fish may vary from 5 to 18 per cent during the packing season. 

 Variation in Fat and Water Content op the Fish. 



Several investigators have noted the fact that the fat content of 

 fish varies with the season, being noticeably low in the spring. Few 

 analyses showing the difference in composition and seasonal variation 

 in the fat content of fish have, however, been reported. According 

 to Dr. John Hjort, director of fisheries of Norway (12), the maximum 

 fat content, 15.52 per cent, in the Norwegian sardine (the brisling) is 

 found in September, and the minimum amount, 4.65 per cent, in 

 April. The amount of fat stored up in the muscular tissue and 

 viscera of the herring during the summer is consumed during the 

 winter. Conversely, the water content is lower during the summer 

 than in the winter months. This fish is inferior in quality through 

 the winter, or period of low fat content. In discussing the quality 

 of fish used for packing sardines, Dr. Hjort stated that "The quality 

 of all three species, herring, brisling, and pilchard, is a feature which 

 changes with age and season." 



H. Lichtenfelt (15) states that the muscular tissue of fish changes in 

 composition at definite periods of the year, the fat content depending 

 on the age of the fish, the food eaten, and the spawning season. 

 During the hunger period (scarcity of food) the percentage of water 

 increases, while that of dry matter and of protein decrease. 



Milroy(18) found great differences in the composition of the muscles 

 of fish of larger size than are commonly used for sardines, taken from 

 the same waters in different months. The percentage of fat in fish, 

 the ovaries of which were immature, was in the summer about the 

 same as the average for herring. During August, September, and 

 October the percentage of fat continued to increase. It decreased 

 slightly in November, more in December, and most markedly during 

 spawning, continuing at a low level until the fish began to feed again. 

 This investigator points out the probability that the decrease in fat 

 in the muscle tissues of the fish is accompanied by an increase in the 

 water content. 



