PRESERVATIOlSr OF FISH BY SALT. 



9 



and they even change in the same individual fish as staleness de- 

 velops. Now, most of these odoriferous substances are soluble in 

 water or brine, and after the salting process would be found in the 

 brine. They are not replaced when the fish is soaked out. It might 

 therefore be anticipated, as has actually been found, that the fresh 

 fish, disagreeable because of the presence of strong substances, are 

 rendered sweet by the removal thereof in the salting process. 



If this lead were followed in detail, it is quite possible that salting 

 would turn out to be the best method of utilizing fishes that are of 

 a rather poor edible quality when in the fresh condition. This aspect 

 of the matter deserves particular attention of the canners. Many 

 species of fish of great abundance might in time be profitably packed 

 if the flavor were inviting. With highly improved technique in 

 salting, the undesirable flavors might be removed by curing and 

 soaking out before canning. This process would be unthinkable oh 

 the basis of the customary salting methods where there is in the 

 end an excessive saltiness or flatness of flavor, but the mild, sweet 

 fish prepared by improved technique and pure salt is a much more 

 promising possibility for canning. 



DRY SALTING AND BRINE SALTING COMPARED. 



The next question taken up in the investigations referred to was 

 that of the relative merits of the application of the salt to fish in 

 the dry state and as a concentrated brine. In the Chesapeake Bay 

 region the herring are usually pickled in brine. By a strict compari- 

 son of the two methods it was found that there is developed a smaller 

 quantity of the products of decomposition — the amino acids — when 

 the salt is applied dry. Not only this, but it was also found that salt 

 applied in the dry condition penetrates the fish more rapidly. 



Am,ong the products of protein decomposition are amino acids. 

 A determination of amino acid nitrogen was taken as a measure of 

 decomposition — the more of the amino acid nitrogen present the 

 greater the amount of decomposition. This being true, the following 

 table, summarized from Tressler's results, will show the superiority 

 of dry salt over strong brine for preserving fish. 



Amounts of Amino Acid Nitrogen Formep Per Kilogram of Fish at Different 



Temperatures. 



